Heavy metals in Corn

Quick read

Monitored maize grain and sweet corn are mostly below reporting limits for lead, cadmium, arsenic and mercury; corn grown downwind of industry, beside power plants, on wastewater-irrigated fields or in mining areas carried several times more.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}^{2U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →}^{3Abatemi-Usman S, Akindele O, Ayanlade A, Perez M, Attahiru I, Norton G, Feldmann J, Krupp E · 2023Trace elements concentrations in soil contaminate corn in the vicinity of a cement-manufacturing plant: potential health implicationsJournal of Exposure Science & Environmental EpidemiologyRead source →}^{4Adel S. El-Hassanin, Magdy R. Samak, Gomaa N. Abdel-Rahman, Yahia H. Abu-Sree, Essam M. Saleh · 2020Risk assessment of human exposure to lead and cadmium in maize grains cultivated in soils irrigated either with low-quality water or freshwaterToxicology Reports 7:10-15Read source →}^{5Li R, Wu H, Ding J, Fu W, Gan L, Li Y · 2017Mercury pollution in vegetables, grains and soils from areas surrounding coal-fired power plantsScientific ReportsRead source →}

Metals of concern:
Lead and cadmium in maize grain from contaminated fields; arsenic where soil or water is high in it; mercury near coal-fired power plants.^{3Abatemi-Usman S, Akindele O, Ayanlade A, Perez M, Attahiru I, Norton G, Feldmann J, Krupp E · 2023Trace elements concentrations in soil contaminate corn in the vicinity of a cement-manufacturing plant: potential health implicationsJournal of Exposure Science & Environmental EpidemiologyRead source →}^{5Li R, Wu H, Ding J, Fu W, Gan L, Li Y · 2017Mercury pollution in vegetables, grains and soils from areas surrounding coal-fired power plantsScientific ReportsRead source →}^{6Liu Q, Li X, He L · 2022Health risk assessment of heavy metals in soils and food crops from a coexist area of heavily industrialized and intensively cropping in the Chengdu Plain, Sichuan, ChinaFrontiers in ChemistryRead source →}^{7Islam MS, Ahmed MK, Habibullah-Al-Mamun M · 2014Heavy Metals in Cereals and Pulses: Health Implications in BangladeshJournal of Agricultural and Food ChemistryRead source →}
Main drivers:
Where the corn grew, irrigation water, the form bought (dry grain or sweet corn) and the basis a result is reported on.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}^{4Adel S. El-Hassanin, Magdy R. Samak, Gomaa N. Abdel-Rahman, Yahia H. Abu-Sree, Essam M. Saleh · 2020Risk assessment of human exposure to lead and cadmium in maize grains cultivated in soils irrigated either with low-quality water or freshwaterToxicology Reports 7:10-15Read source →}^{8Gu Q, Yu T, Yang Z, Ji J, Hou Q, Wang L, Wei X, Zhang Q · 2019Prediction and risk assessment of five heavy metals in maize and peanut: a case study of Guangxi, ChinaEnvironmental Toxicology and PharmacologyRead source →}
Practical framing:
Ask for lot results with quantification limits well below 200 µg/kg lead and 100 µg/kg cadmium for grain, or 20 µg/kg cadmium for sweet corn.^{9European Commission · 2023Commission Regulation (EU) 2023/915 of 25 April 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source →}^{10Codex Alimentarius Commission · 1995General Standard for Contaminants and Toxins in Food and Feed (CXS 193-1995)Codex Alimentarius (Joint FAO/WHO Food Standards Programme)Read source →}

Corn overview

Most corn sold as maize grain or sweet corn carries lead, cadmium, arsenic and mercury below or near the limits laboratories can measure. In WHO GEMS/Food, European maize grain had a median lead result below 20 µg/kg across 890 results from 2001 to 2020, and 8 exceeded the EU and Codex cereal limit of 200 µg/kg; cadmium had a median below 3.2 µg/kg, with 3 of 1,238 results above the 100 µg/kg limit.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}^{9European Commission · 2023Commission Regulation (EU) 2023/915 of 25 April 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source →}^{10Codex Alimentarius Commission · 1995General Standard for Contaminants and Toxins in Food and Feed (CXS 193-1995)Codex Alimentarius (Joint FAO/WHO Food Standards Programme)Read source →} Frozen corn boiled as eaten in the US Total Diet Study had lead, arsenic and mercury below detection in all 27 national composites, and a median cadmium of 2.6 µg/kg.^{2U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →}

The exceptions come from where the corn grew. Maize from farms downwind of a Nigerian cement plant averaged 230–380 µg/kg lead against 20 µg/kg at a control farm, maize irrigated with wastewater in Egypt carried 260–550 µg/kg lead against 30–40 µg/kg or less with fresh or ground water, and maize within 1 km of Chinese coal-fired power plants held about 21 µg/kg mercury against about 1 µg/kg at 5 km and 0.72 µg/kg in maize from a distant grocery store.^{3Abatemi-Usman S, Akindele O, Ayanlade A, Perez M, Attahiru I, Norton G, Feldmann J, Krupp E · 2023Trace elements concentrations in soil contaminate corn in the vicinity of a cement-manufacturing plant: potential health implicationsJournal of Exposure Science & Environmental EpidemiologyRead source →}^{4Adel S. El-Hassanin, Magdy R. Samak, Gomaa N. Abdel-Rahman, Yahia H. Abu-Sree, Essam M. Saleh · 2020Risk assessment of human exposure to lead and cadmium in maize grains cultivated in soils irrigated either with low-quality water or freshwaterToxicology Reports 7:10-15Read source →}^{5Li R, Wu H, Ding J, Fu W, Gan L, Li Y · 2017Mercury pollution in vegetables, grains and soils from areas surrounding coal-fired power plantsScientific ReportsRead source →} Field surveys in China, Bangladesh and Burkina Faso also report cadmium or lead in ordinary maize at or above the cereal limits, though several use dry-weight or unstated bases that cannot be set directly beside monitoring results.^{6Liu Q, Li X, He L · 2022Health risk assessment of heavy metals in soils and food crops from a coexist area of heavily industrialized and intensively cropping in the Chengdu Plain, Sichuan, ChinaFrontiers in ChemistryRead source →}^{7Islam MS, Ahmed MK, Habibullah-Al-Mamun M · 2014Heavy Metals in Cereals and Pulses: Health Implications in BangladeshJournal of Agricultural and Food ChemistryRead source →}^{11Bazie SR, Compaore MKA, Bande M, Kpoda SD, Meda NSBR, Ouedraogo Kangambega TM, Ilboudo I, Sandwidi BY, Nikiema F, Yakoro A, Bassole IHN, Hien H, Kabre E · 2022Evaluation of metallic trace elements contents in some major raw foodstuffs in Burkina Faso and health risk assessmentScientific ReportsRead source →}^{12Li X, Zhou L, Zhang C, Li D, Wang Z, Sun D, Liao C, Zhang Q · 2022Spatial distribution and risk assessment of fluorine and cadmium in rice, corn, and wheat grains in most karst regions of Guizhou province, ChinaFrontiers in NutritionRead source →}

For a buyer the practical points are the growing area, the form bought and the laboratory’s quantification limit. Maize grain and sweet corn have different legal limits: the EU allows 200 µg/kg lead and 100 µg/kg cadmium in cereals but 100 µg/kg lead and 20 µg/kg cadmium in sweet corn, on a wet-weight basis.^{9European Commission · 2023Commission Regulation (EU) 2023/915 of 25 April 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source →} Lot results with a quantification limit well below those values are the supported check; testing finds contamination but does not remove it.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}^{9European Commission · 2023Commission Regulation (EU) 2023/915 of 25 April 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source →}

What counts as corn

This page covers corn (Zea mays) in two forms that are measured and regulated differently: mature maize grain, the dry kernels sold as a cereal, and fresh corn, meaning sweet corn or green ears eaten as a vegetable raw, frozen or cooked, together with baby corn.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}^{2U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →}^{9European Commission · 2023Commission Regulation (EU) 2023/915 of 25 April 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source →} Each form is kept separate because sweet corn is mostly water and grain is dry, so the same amount of metal gives a much lower concentration per kilogram of sweet corn.^{9European Commission · 2023Commission Regulation (EU) 2023/915 of 25 April 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source →}^{10Codex Alimentarius Commission · 1995General Standard for Contaminants and Toxins in Food and Feed (CXS 193-1995)Codex Alimentarius (Joint FAO/WHO Food Standards Programme)Read source →}

Foods made from corn have their own pages and their results are not used here: canned corn, corn flour and meal, grits, polenta, corn flakes, popcorn, tortillas, cornbread, corn oil and corn syrup.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}^{2U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →} Animal feed, maize silage, infant cereals that contain corn and corn salad, a leafy vegetable that is not corn at all, are also outside this page.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}

Results are kept on the basis each source reports. Monitoring programmes report corn as sold or as eaten, field studies often report dried grain, and several papers do not say which, so dry-weight, as-sold and unstated results are never pooled.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}^{3Abatemi-Usman S, Akindele O, Ayanlade A, Perez M, Attahiru I, Norton G, Feldmann J, Krupp E · 2023Trace elements concentrations in soil contaminate corn in the vicinity of a cement-manufacturing plant: potential health implicationsJournal of Exposure Science & Environmental EpidemiologyRead source →}^{11Bazie SR, Compaore MKA, Bande M, Kpoda SD, Meda NSBR, Ouedraogo Kangambega TM, Ilboudo I, Sandwidi BY, Nikiema F, Yakoro A, Bassole IHN, Hien H, Kabre E · 2022Evaluation of metallic trace elements contents in some major raw foodstuffs in Burkina Faso and health risk assessmentScientific ReportsRead source →}^{13Abdullahi N, Dandago MA, Gambo MS, Abubakar SS, Tsoho AU, Idah PG · 2024Seasonal Variation and Uptake Pattern of Heavy Metals in MaizeDutse Journal of Pure and Applied Sciences (DUJOPAS)Read source →}

Heavy metal contamination profile of corn

The table holds every corn result extracted from WHO GEMS/Food, the FDA Total Diet Study and 30 field, market and contaminated-site studies: one row for each statistic a source reports for a form of corn, group and metal.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}^{2U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →}^{3Abatemi-Usman S, Akindele O, Ayanlade A, Perez M, Attahiru I, Norton G, Feldmann J, Krupp E · 2023Trace elements concentrations in soil contaminate corn in the vicinity of a cement-manufacturing plant: potential health implicationsJournal of Exposure Science & Environmental EpidemiologyRead source →}^{4Adel S. El-Hassanin, Magdy R. Samak, Gomaa N. Abdel-Rahman, Yahia H. Abu-Sree, Essam M. Saleh · 2020Risk assessment of human exposure to lead and cadmium in maize grains cultivated in soils irrigated either with low-quality water or freshwaterToxicology Reports 7:10-15Read source →}^{5Li R, Wu H, Ding J, Fu W, Gan L, Li Y · 2017Mercury pollution in vegetables, grains and soils from areas surrounding coal-fired power plantsScientific ReportsRead source →}^{6Liu Q, Li X, He L · 2022Health risk assessment of heavy metals in soils and food crops from a coexist area of heavily industrialized and intensively cropping in the Chengdu Plain, Sichuan, ChinaFrontiers in ChemistryRead source →}^{7Islam MS, Ahmed MK, Habibullah-Al-Mamun M · 2014Heavy Metals in Cereals and Pulses: Health Implications in BangladeshJournal of Agricultural and Food ChemistryRead source →}^{14Romero-Crespo P, Jiménez-Oyola S, Salgado-Almeida B, Zambrano-Anchundia J, Goyburo-Chávez C, González-Valoys A, Higueras P · 2023Trace elements in farmland soils and crops, and probabilistic health risk assessment in areas influenced by mining activity in EcuadorEnvironmental Geochemistry and HealthRead source →}^{11Bazie SR, Compaore MKA, Bande M, Kpoda SD, Meda NSBR, Ouedraogo Kangambega TM, Ilboudo I, Sandwidi BY, Nikiema F, Yakoro A, Bassole IHN, Hien H, Kabre E · 2022Evaluation of metallic trace elements contents in some major raw foodstuffs in Burkina Faso and health risk assessmentScientific ReportsRead source →}^{15Saleem M, Wang Y, Pierce D, Sens DA, Somji S, Garrett SH · 2025Concentration and Potential Non-Carcinogenic and Carcinogenic Health Risk Assessment of Metals in Locally Grown VegetablesFoodsRead source →}^{16Jiang Y, Ma J, Ruan X · 2020Compound health risk assessment of cumulative heavy metal exposure: A case study of a village near a battery factory in Henan Province, ChinaEnvironmental Science: Processes & ImpactsRead source →}^{17Bedoya-Perales NS, Escobedo-Pacheco E, Maus D, Neimaier A, Pumi G · 2023Dataset of metals and metalloids in food crops and soils sampled across the mining region of Moquegua in PeruScientific DataRead source →}^{12Li X, Zhou L, Zhang C, Li D, Wang Z, Sun D, Liao C, Zhang Q · 2022Spatial distribution and risk assessment of fluorine and cadmium in rice, corn, and wheat grains in most karst regions of Guizhou province, ChinaFrontiers in NutritionRead source →}^{13Abdullahi N, Dandago MA, Gambo MS, Abubakar SS, Tsoho AU, Idah PG · 2024Seasonal Variation and Uptake Pattern of Heavy Metals in MaizeDutse Journal of Pure and Applied Sciences (DUJOPAS)Read source →}^{18Liu Z, Wang L, Yan M, Tian Y, Ma B, Xie Q · 2025Heavy metal synergistic pollution risk assessment in the soil-crop system of the Nanyang BasinScientific ReportsRead source →}^{19Edirisinghe EMRKB, Jinadasa BKKK · 2019Arsenic and cadmium concentrations in legumes and cereals grown in the North Central Province, Sri Lanka and assessment of their health riskInternational Journal of Food Contamination 6:3Read source →}^{20wheat flour marketed in Shanghai City Zuoyin Zhu, Wenbo Guo, Haisheng Cheng, Hanke Zhao, Jie Wang, Mohamed F. Abdallah, Xinli Zhou, Hulong Lei · 2024mycotoxins and heavy metals in rice, maize,Peer-reviewed articleRead source →} GEMS/Food rows are HMI-calculated medians of individual national submissions by WHO region, sampling type and basis; non-detects remain intervals between zero and the reporting limit and are never read as zero.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}

Ratings place a result against an HMI reference for the same form of corn and basis, built from GEMS/Food region-by-year medians, the 27 FDA composites for cooked sweet corn and printed medians from ordinary farms and markets.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}^{2U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →}^{19Edirisinghe EMRKB, Jinadasa BKKK · 2019Arsenic and cadmium concentrations in legumes and cereals grown in the North Central Province, Sri Lanka and assessment of their health riskInternational Journal of Food Contamination 6:3Read source →} Because more than half of most monitoring results are below reporting limits, many medians span the reference quartiles and cannot be placed; those rows are left unrated rather than forced into a category.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}^{2U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →}

Field studies in contaminated areas are shown with their own controls instead of being rated against ordinary corn.^{3Abatemi-Usman S, Akindele O, Ayanlade A, Perez M, Attahiru I, Norton G, Feldmann J, Krupp E · 2023Trace elements concentrations in soil contaminate corn in the vicinity of a cement-manufacturing plant: potential health implicationsJournal of Exposure Science & Environmental EpidemiologyRead source →}^{4Adel S. El-Hassanin, Magdy R. Samak, Gomaa N. Abdel-Rahman, Yahia H. Abu-Sree, Essam M. Saleh · 2020Risk assessment of human exposure to lead and cadmium in maize grains cultivated in soils irrigated either with low-quality water or freshwaterToxicology Reports 7:10-15Read source →}^{5Li R, Wu H, Ding J, Fu W, Gan L, Li Y · 2017Mercury pollution in vegetables, grains and soils from areas surrounding coal-fired power plantsScientific ReportsRead source →} Values that fail a check against their own paper are held and stay visible with the reason, including a mining-area maize table that duplicates another crop’s values, a cadmium result with a standard deviation near its mean in a single composite, and conflicting means across one paper’s tables.^{21Zhang Y, Li X, Kong F · 2026Trace metal pollution and ecological effects on five crops around a typical manganese mining area in Chongqing, ChinaScientific ReportsRead source →}^{22Getu A, Seid Y, Asrade B · 2022Determination of the Level of Heavy Metals in the Selected Cereals from Debre Markos Local Market, Amhara Region, EthiopiaInternational Journal of Analytical ChemistryRead source →}^{23Gholami Z, Mohammadi Rouzbahani M, Payandeh K, Sabzalipour S · 2025Health risk assessment Pb, As and Cr in corn (Zea mays) of Behbahan and Dezful from Khuzestan Province, IranScientific ReportsRead source →}^{24Islam MS, Ahmed MK, Habibullah-Al-Mamun M, Raknuzzaman M · 2015The concentration, source and potential human health risk of heavy metals in the commonly consumed foods in BangladeshEcotoxicology and Environmental SafetyRead source →}^{25Ibrahim UM, Karkarna MZ, Babura SM, Matazu MA, Jibo AM, Umar ML, Aliyu MH · 2024Correlates of Food Contamination by Heavy Metals in Northwest NigeriaEnvironmental Health InsightsRead source →}

Comparison methods and scope

Each row is one statistic a source reports for one form of corn, group and metal. Maize grain, fresh or frozen sweet corn, cooked sweet corn and baby corn are kept apart, and dry-weight results never share a reference with as-sold or fresh-weight results. Ratings place a result against an HMI reference built from monitoring results and ordinary-field medians for the same form and basis. Same-study contrasts compare a polluted site with its control, one season with another, or cooked with raw sweet corn. Held rows failed a check against their own paper and are shown but not compared.

Filter findings

AnalyteFood formCollection regionCollection periodSourceCompare withComparable findings only

437 of 437 findings · 10 analytes

About this table

Food formCollection scopeFindingComparisonEvidence

Corn findings from WHO GEMS/Food monitoring, the FDA Total Diet Study and every extracted field, market and contaminated-site study, in µg/kg with each source’s form of corn, basis, statistic and censoring retained.
Food form	Collection scope	Finding (µg/kg)

89 findings · 22 studies · 19 spread figures folded in
Maize grainWHO GEMS/Food	EURO, random2001–2020As sold / fresh	median.
Maize grainWHO GEMS/Food	EURO, sampling unstated2003–2017As sold / fresh	median.
Maize grainWHO GEMS/Food	SEARO, targeted2010–2011As sold / fresh	median.
Maize grainWHO GEMS/Food	WPRO, random2005–2010As sold / fresh	median.
Maize grainWHO GEMS/Food	WPRO, targeted2001As sold / fresh	median.
Maize grainIslam et al. 2015	Bogra district, Bangladesh2012As sold / fresh	mean.
Maize grainIslam et al. 2015	Bogra district, Bangladesh2012As sold / fresh	range.
Maize grainWHO GEMS/Food	AFRO, random2012Dry weight	median.
Maize grainAbatemi-Usman et al. 2023	Farm 2.7 km upwind of cement plant2017Dry weight	median.
Maize grainAbatemi-Usman et al. 2023	Farm 2.7 km upwind of cement plant2017Dry weight	mean.Same samples: up to 50 µg/kg (range; minimum not quantified)
Maize grainAbatemi-Usman et al. 2023	Farm 2.7 km upwind of cement plant2017Dry weight	range.
Maize grainAbatemi-Usman et al. 2023	Farm 0.7 km downwind of cement plant2017Dry weight	median.
Maize grainAbatemi-Usman et al. 2023	Farm 0.7 km downwind of cement plant2017Dry weight	mean.Same samples: up to 360 µg/kg (range; minimum not quantified)
Maize grainAbatemi-Usman et al. 2023	Farm 0.7 km downwind of cement plant2017Dry weight	range.
Maize grainAbatemi-Usman et al. 2023	Farm 3.1 km downwind of cement plant2017Dry weight	median.
Maize grainAbatemi-Usman et al. 2023	Farm 3.1 km downwind of cement plant2017Dry weight	mean.Same samples: 250–510 µg/kg (range)
Maize grainAbatemi-Usman et al. 2023	Farm 3.1 km downwind of cement plant2017Dry weight	range.
Maize grainAbatemi-Usman et al. 2023	Farm 2.3 km downwind of cement plant2017Dry weight	median.
Maize grainAbatemi-Usman et al. 2023	Farm 2.3 km downwind of cement plant2017Dry weight	mean.Same samples: 290–600 µg/kg (range)
Maize grainAbatemi-Usman et al. 2023	Farm 2.3 km downwind of cement plant2017Dry weight	range.
Maize grainAbatemi-Usman et al. 2023	Control farm, 18 km upwind of cement plant2017Dry weight	median.
Maize grainAbatemi-Usman et al. 2023	Control farm, 18 km upwind of cement plant2017Dry weight	mean.Same samples: 10–90 µg/kg (range)
Maize grainAbatemi-Usman et al. 2023	Control farm, 18 km upwind of cement plant2017Dry weight	range.
Maize grainGetu et al. 2022	Debre Markos market, Ethiopia2020Dry weight	mean.
Maize grainGu et al. 2019	Binyang and Xingbin fields, Guangxi2015Dry weight	median.Same samples: 22–148 µg/kg (range)
Maize grainGu et al. 2019	Binyang and Xingbin fields, Guangxi2015Dry weight	range.
Maize grainIslam et al. 2014	Bogra district fields, Bangladesh2012Dry weight	mean.Same samples: 44–1,300 µg/kg (range)
Maize grainIslam et al. 2014	Bogra district fields, Bangladesh2012Dry weight	range.
Maize grainLiu et al. 2022	Shifang area fields near ChengduCollection date unreportedDry weight	mean.Same samples: 20–500 µg/kg (range)
Maize grainLiu et al. 2022	Shifang area fields near ChengduCollection date unreportedDry weight	range.
Maize grainLiu et al. 2025	Nanyang Basin fields, HenanCollection date unreportedDry weight	mean.Same samples: up to 78 µg/kg (range; minimum not quantified)
Maize grainLiu et al. 2025	Nanyang Basin fields, HenanCollection date unreportedDry weight	range.
Maize grainPirsaheb et al. 2015	Kermanshah retail, Iran2014Dry weight	mean.Same samples: 700–1,950 µg/kg (range)
Maize grainPirsaheb et al. 2015	Kermanshah retail, Iran2014Dry weight	range.
Maize grainZhang et al. 2026	Manganese mining and smelting area2020Dry weight	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, all 10 locations2023Basis not stated	mean.Same samples: 1,540–2,350 µg/kg (range)
Maize grainAbdullahi et al. 2024	Dry season 2023, all 10 locations2023Basis not stated	range.
Maize grainAbdullahi et al. 2024	Dry season 2023, Bulan Wanzamai2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Gafan2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Gafan Bunkure2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Gafan II2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Imawa (Gada Mailotso)2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Imawa (Rimin Kwarya)2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Kukoki2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Kura (Babbar Gada)2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Kura (Fegin Malu)2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Kwalele2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Wet season 2022, all 10 locations2022Basis not stated	mean.Same samples: 1,260–2,670 µg/kg (range)
Maize grainAbdullahi et al. 2024	Wet season 2022, all 10 locations2022Basis not stated	range.
Maize grainAbdullahi et al. 2024	Wet season 2022, Dakasoye2022Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Wet season 2022, Gafan2022Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Wet season 2022, Imawa I2022Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Wet season 2022, Imawa II2022Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Wet season 2022, Kura (Gorubawa)2022Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Wet season 2022, Kura (Tsauni)2022Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Wet season 2022, Makuntiri2022Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Wet season 2022, Rigada2022Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Wet season 2022, Yadakwari2022Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Wet season 2022, Yantomo2022Basis not stated	mean.
Maize grainAtaee et al. 2016	Kermanshah market 1, IranCollection date unreportedBasis not stated	mean.
Maize grainAtaee et al. 2016	Kermanshah market 2, IranCollection date unreportedBasis not stated	mean.
Maize grainAtaee et al. 2016	Kermanshah market 3, IranCollection date unreportedBasis not stated	mean.
Maize grainBazie et al. 2022	Bobo Dioulasso2020Basis not stated	median.Same samples: up to 460 µg/kg (range; minimum not quantified)
Maize grainBazie et al. 2022	Bobo Dioulasso2020Basis not stated	range.
Maize grainBazie et al. 2022	Cinkasse2020Basis not stated	median.Same samples: up to 460 µg/kg (range; minimum not quantified)
Maize grainBazie et al. 2022	Cinkasse2020Basis not stated	range.
Maize grainBazie et al. 2022	Dakola2020Basis not stated	median.
Maize grainBazie et al. 2022	Dakola2020Basis not stated	range.
Maize grainBazie et al. 2022	Niankologo2020Basis not stated	median.Same samples: up to 1,480 µg/kg (range; minimum not quantified)
Maize grainBazie et al. 2022	Niankologo2020Basis not stated	range.
Maize grainBazie et al. 2022	Ouagadougou2020Basis not stated	median.Same samples: up to 780 µg/kg (range; minimum not quantified)
Maize grainBazie et al. 2022	Ouagadougou2020Basis not stated	range.
Maize grainBazie et al. 2022	Total (all maize samples)2020Basis not stated	median.Same samples: up to 1,480 µg/kg (range; minimum not quantified)
Maize grainBazie et al. 2022	Total (all maize samples)2020Basis not stated	range.
Maize grainBedoya-Perales et al. 2023	Carumas district, Moquegua2021Basis not stated	median.
Maize grainBedoya-Perales et al. 2023	Chojata district, Moquegua2021Basis not stated	median.
Maize grainBedoya-Perales et al. 2023	Matalaque district, Moquegua2021Basis not stated	median.
Maize grainEl-Hassanin et al. 2020	Abdel-Rahman (fresh or ground water)2017Basis not stated	below LOD.
Maize grainEl-Hassanin et al. 2020	Abdel-Rakib2017Basis not stated	mean.
Maize grainEl-Hassanin et al. 2020	Abdel-Wahab2017Basis not stated	below LOD.
Maize grainEl-Hassanin et al. 2020	Abo-Roash (wastewater-irrigated)2017Basis not stated	mean.
Maize grainEl-Hassanin et al. 2020	Al-Hawia (fresh or ground water)2017Basis not stated	mean.
Maize grainEl-Hassanin et al. 2020	Al-Nasiria (wastewater-irrigated)2017Basis not stated	mean.
Maize grainEl-Hassanin et al. 2020	Kafr-Dokhmais (wastewater-irrigated)2017Basis not stated	mean.
Maize grainEl-Hassanin et al. 2020	Kafr-Hakem (wastewater-irrigated)2017Basis not stated	mean.
Maize grainEl-Hassanin et al. 2020	Wadi El-Natron (fresh or ground water)2017Basis not stated	below LOD.
Maize grainGholami et al. 2025	All samples 2022 (abstract)2022Basis not stated	mean.
Maize grainGholami et al. 2025	All samples 20222022Basis not stated	mean.
Maize grainGholami et al. 2025	Behbahan Autumn 20222022Basis not stated	mean.
Maize grainGholami et al. 2025	Behbahan both seasons 20222022Basis not stated	mean.
Maize grainGholami et al. 2025	Behbahan Summer 20222022Basis not stated	mean.
Maize grainGholami et al. 2025	Both cities Autumn 20222022Basis not stated	mean.
Maize grainGholami et al. 2025	Both cities Summer 20222022Basis not stated	mean.
Maize grainGholami et al. 2025	Dezfoul Autumn 20222022Basis not stated	mean.
Maize grainGholami et al. 2025	Dezfoul Summer 20222022Basis not stated	mean.
Maize grainGholami et al. 2025	Dezful both seasons 20222022Basis not stated	mean.
Maize grainGholami et al. 2025	Seasonal means span (discussion)2022Basis not stated	range.
Maize grainIbrahim et al. 2024	Maize-eating households, Jigawa, Nigeria2023Basis not stated	median.
Maize grainJiang et al. 2020	Village 2.5 km from battery plant2018Basis not stated	mean.Same samples: 110–190 µg/kg (range)
Maize grainJiang et al. 2020	Village 2.5 km from battery plant2018Basis not stated	range.
Maize grainMustapha et al. 2024	Hybrid maize, Central market, BauchiCollection date unreportedBasis not stated	mean.
Maize grainMustapha et al. 2024	Hybrid maize, Muda Lawal market, BauchiCollection date unreportedBasis not stated	not detected.
Maize grainMustapha et al. 2024	Syria maize, Central market, BauchiCollection date unreportedBasis not stated	mean.
Maize grainMustapha et al. 2024	Syria maize, Muda Lawal market, BauchiCollection date unreportedBasis not stated	mean.
Maize grainRomán-Ochoa et al. 2021	Arequipa growing districts, Peru2019Basis not stated	mean.
Maize grainRubio et al. 2023	Madeira markets, PortugalCollection date unreportedBasis not stated	mean.
Maize grainZhu et al. 2024	Shanghai supermarkets and markets2021–2022Basis not stated	mean.Same samples: 51–1,340 µg/kg (range)
Maize grainZhu et al. 2024	Shanghai supermarkets and markets2021–2022Basis not stated	range.
7 findings · 3 studies
Sweet or fresh corn, raw or frozenWHO GEMS/Food	EURO, random2004–2019As sold / fresh	median.
Sweet or fresh corn, raw or frozenWHO GEMS/Food	EURO, sampling unstated2011As sold / fresh	median.
Sweet or fresh corn, raw or frozenWHO GEMS/Food	PAHO, random2014–2016As sold / fresh	median.
Sweet or fresh corn, raw or frozenWHO GEMS/Food	SEARO, random2011–2014As sold / fresh	median.
Sweet or fresh corn, raw or frozenWHO GEMS/Food	WPRO, random2004–2012As sold / fresh	median.
Sweet or fresh corn, raw or frozenAgarwal et al. 2022	Dhapa waste-dumping ground, Kolkata2016–2017Dry weight	range.
Sweet or fresh corn, raw or frozenSaleem et al. 2025	Grand Forks farmers’ market, USCollection date unreportedDry weight	mean.
6 findings · 3 studies
Sweet corn, cooked as eatenWHO GEMS/Food	EURO, random2010–2012As sold / fresh	median.
Sweet corn, cooked as eatenWHO GEMS/Food	PAHO, random2000–2017As sold / fresh	median.
Sweet corn, cooked as eatenWHO GEMS/Food	WPRO, random2014As sold / fresh	median.
Sweet corn, cooked as eatenWHO GEMS/Food	WPRO, targeted2008As sold / fresh	median.
Sweet corn, cooked as eatenFDA Total Diet Study	United States, four regions2017–2020As sold / fresh	median.
Sweet corn, cooked as eatenMasite et al. 2022	Limpopo produce markets, South Africa2019Dry weight	not detected.
1 finding · 1 study
Sweet corn, pack not statedWHO GEMS/Food	PAHO, random2003–2016As sold / fresh	median.
3 findings · 1 study
Baby cornWHO GEMS/Food	PAHO, random2014As sold / fresh	median.
Baby cornWHO GEMS/Food	SEARO, random2013–2014As sold / fresh	median.
Baby cornWHO GEMS/Food	WPRO, random2013As sold / fresh	median.
3 findings · 1 study
Corn, cooked, form not statedWHO GEMS/Food	AFRO, random2018As sold / fresh	median.
Corn, cooked, form not statedWHO GEMS/Food	EURO, random2007–2017As sold / fresh	median.
Corn, cooked, form not statedWHO GEMS/Food	WPRO, random2010–2011As sold / fresh	median.
1 finding · 1 study
Corn, form not statedRomero-Crespo et al. 2023	Gold-mining orchard, Ecuador2021As sold / fresh	below LOD.

81 findings · 23 studies · 23 spread figures folded in
Maize grainWHO GEMS/Food	EURO, random2001–2020As sold / fresh	median.
Maize grainWHO GEMS/Food	EURO, targeted2003–2006As sold / fresh	median.
Maize grainWHO GEMS/Food	EURO, sampling unstated2003–2017As sold / fresh	median.
Maize grainWHO GEMS/Food	WPRO, random2005As sold / fresh	median.
Maize grainWHO GEMS/Food	WPRO, targeted2001As sold / fresh	median.
Maize grainEdirisinghe et al. 2019	North Central Province farms, Sri Lanka2016As sold / fresh	median.
Maize grainEdirisinghe et al. 2019	North Central Province farms, Sri Lanka2016As sold / fresh	mean.Same samples: up to 122 µg/kg (range; minimum not quantified)
Maize grainEdirisinghe et al. 2019	North Central Province farms, Sri Lanka2016As sold / fresh	range.
Maize grainIslam et al. 2015	Bogra district, Bangladesh2012As sold / fresh	mean.
Maize grainIslam et al. 2015	Bogra district, Bangladesh2012As sold / fresh	range.
Maize grainWHO GEMS/Food	AFRO, random2012Dry weight	median.
Maize grainAbatemi-Usman et al. 2023	Farm 2.7 km upwind of cement plant2017Dry weight	median.
Maize grainAbatemi-Usman et al. 2023	Farm 2.7 km upwind of cement plant2017Dry weight	mean.Same samples: up to 10 µg/kg (range; minimum not quantified)
Maize grainAbatemi-Usman et al. 2023	Farm 2.7 km upwind of cement plant2017Dry weight	range.
Maize grainAbatemi-Usman et al. 2023	Farm 0.7 km downwind of cement plant2017Dry weight	median.
Maize grainAbatemi-Usman et al. 2023	Farm 0.7 km downwind of cement plant2017Dry weight	mean.Same samples: up to 30 µg/kg (range; minimum not quantified)
Maize grainAbatemi-Usman et al. 2023	Farm 0.7 km downwind of cement plant2017Dry weight	range.
Maize grainAbatemi-Usman et al. 2023	Farm 3.1 km downwind of cement plant2017Dry weight	below LOD.
Maize grainAbatemi-Usman et al. 2023	Farm 2.3 km downwind of cement plant2017Dry weight	median.
Maize grainAbatemi-Usman et al. 2023	Farm 2.3 km downwind of cement plant2017Dry weight	mean.Same samples: up to 10 µg/kg (range; minimum not quantified)
Maize grainAbatemi-Usman et al. 2023	Farm 2.3 km downwind of cement plant2017Dry weight	range.
Maize grainAbatemi-Usman et al. 2023	Control farm, 18 km upwind of cement plant2017Dry weight	median.
Maize grainAbatemi-Usman et al. 2023	Control farm, 18 km upwind of cement plant2017Dry weight	mean.Same samples: up to 10 µg/kg (range; minimum not quantified)
Maize grainAbatemi-Usman et al. 2023	Control farm, 18 km upwind of cement plant2017Dry weight	range.
Maize grainGetu et al. 2022	Debre Markos market, Ethiopia2020Dry weight	mean.
Maize grainGu et al. 2019	Binyang and Xingbin fields, Guangxi2015Dry weight	median.Same samples: 2–70 µg/kg (range)
Maize grainGu et al. 2019	Binyang and Xingbin fields, Guangxi2015Dry weight	range.
Maize grainIslam et al. 2014	Bogra district fields, Bangladesh2012Dry weight	mean.Same samples: 18–530 µg/kg (range)
Maize grainIslam et al. 2014	Bogra district fields, Bangladesh2012Dry weight	range.
Maize grainLi et al. 2022	All corn fields, Guizhou karst2021Dry weight	mean.Same samples: up to 307 µg/kg (range; minimum not quantified)
Maize grainLi et al. 2022	All corn fields, Guizhou karst2021Dry weight	range.
Maize grainLi et al. 2022	Concentration class 1 of 52021Dry weight	median.
Maize grainLi et al. 2022	Concentration class 1 of 52021Dry weight	mean.Same samples: up to 34 µg/kg (range; minimum not quantified)
Maize grainLi et al. 2022	Concentration class 1 of 52021Dry weight	range.
Maize grainLi et al. 2022	Concentration class 2 of 52021Dry weight	median.
Maize grainLi et al. 2022	Concentration class 2 of 52021Dry weight	mean.Same samples: 35–69 µg/kg (range)
Maize grainLi et al. 2022	Concentration class 2 of 52021Dry weight	range.
Maize grainLi et al. 2022	Concentration class 3 of 52021Dry weight	median.
Maize grainLi et al. 2022	Concentration class 3 of 52021Dry weight	mean.Same samples: 70–89 µg/kg (range)
Maize grainLi et al. 2022	Concentration class 3 of 52021Dry weight	range.
Maize grainLi et al. 2022	Concentration class 4 of 52021Dry weight	median.
Maize grainLi et al. 2022	Concentration class 4 of 52021Dry weight	mean.Same samples: 90–192 µg/kg (range)
Maize grainLi et al. 2022	Concentration class 4 of 52021Dry weight	range.
Maize grainLi et al. 2022	Concentration class 5 of 52021Dry weight	median.
Maize grainLi et al. 2022	Concentration class 5 of 52021Dry weight	mean.Same samples: 193–307 µg/kg (range)
Maize grainLi et al. 2022	Concentration class 5 of 52021Dry weight	range.
Maize grainLiu et al. 2022	Shifang area fields near ChengduCollection date unreportedDry weight	mean.Same samples: 50–770 µg/kg (range)
Maize grainLiu et al. 2022	Shifang area fields near ChengduCollection date unreportedDry weight	range.
Maize grainLiu et al. 2025	Nanyang Basin fields, HenanCollection date unreportedDry weight	mean.Same samples: up to 467 µg/kg (range; minimum not quantified)
Maize grainLiu et al. 2025	Nanyang Basin fields, HenanCollection date unreportedDry weight	range.
Maize grainPirsaheb et al. 2015	Kermanshah retail, Iran2014Dry weight	mean.Same samples: 50–1,050 µg/kg (range)
Maize grainPirsaheb et al. 2015	Kermanshah retail, Iran2014Dry weight	range.
Maize grainZhang et al. 2026	Manganese mining and smelting area2020Dry weight	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, all 10 locations2023Basis not stated	mean.Same samples: 160–200 µg/kg (range)
Maize grainAbdullahi et al. 2024	Dry season 2023, all 10 locations2023Basis not stated	range.
Maize grainAbdullahi et al. 2024	Dry season 2023, Bulan Wanzamai2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Gafan2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Gafan Bunkure2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Gafan II2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Imawa (Gada Mailotso)2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Imawa (Rimin Kwarya)2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Kukoki2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Kura (Babbar Gada)2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Kura (Fegin Malu)2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Kwalele2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Wet season 2022, all 10 locations2022Basis not stated	not detected.
Maize grainAtaee et al. 2016	Kermanshah market 1, IranCollection date unreportedBasis not stated	mean.
Maize grainAtaee et al. 2016	Kermanshah market 2, IranCollection date unreportedBasis not stated	mean.
Maize grainAtaee et al. 2016	Kermanshah market 3, IranCollection date unreportedBasis not stated	mean.
Maize grainBazie et al. 2022	Bobo Dioulasso2020Basis not stated	median.Same samples: up to 480 µg/kg (range; minimum not quantified)
Maize grainBazie et al. 2022	Bobo Dioulasso2020Basis not stated	range.
Maize grainBazie et al. 2022	Cinkasse2020Basis not stated	median.Same samples: up to 480 µg/kg (range; minimum not quantified)
Maize grainBazie et al. 2022	Cinkasse2020Basis not stated	range.
Maize grainBazie et al. 2022	Dakola2020Basis not stated	median.Same samples: up to 250 µg/kg (range; minimum not quantified)
Maize grainBazie et al. 2022	Dakola2020Basis not stated	range.
Maize grainBazie et al. 2022	Niankologo2020Basis not stated	median.Same samples: up to 500 µg/kg (range; minimum not quantified)
Maize grainBazie et al. 2022	Niankologo2020Basis not stated	range.
Maize grainBazie et al. 2022	Ouagadougou2020Basis not stated	below LOD.
Maize grainBazie et al. 2022	Ouagadougou2020Basis not stated	range.
Maize grainBazie et al. 2022	Total (all maize samples)2020Basis not stated	below LOD.
Maize grainBazie et al. 2022	Total (all maize samples)2020Basis not stated	range.
Maize grainBedoya-Perales et al. 2023	Carumas district, Moquegua2021Basis not stated	median.
Maize grainBedoya-Perales et al. 2023	Chojata district, Moquegua2021Basis not stated	median.
Maize grainBedoya-Perales et al. 2023	Matalaque district, Moquegua2021Basis not stated	median.
Maize grainEl-Hassanin et al. 2020	Abdel-Rahman (fresh or ground water)2017Basis not stated	below LOD.
Maize grainEl-Hassanin et al. 2020	Abdel-Rakib2017Basis not stated	below LOD.
Maize grainEl-Hassanin et al. 2020	Abdel-Wahab2017Basis not stated	below LOD.
Maize grainEl-Hassanin et al. 2020	Abo-Roash (wastewater-irrigated)2017Basis not stated	mean.
Maize grainEl-Hassanin et al. 2020	Al-Hawia (fresh or ground water)2017Basis not stated	mean.
Maize grainEl-Hassanin et al. 2020	Al-Nasiria (wastewater-irrigated)2017Basis not stated	mean.
Maize grainEl-Hassanin et al. 2020	Kafr-Dokhmais (wastewater-irrigated)2017Basis not stated	mean.
Maize grainEl-Hassanin et al. 2020	Kafr-Hakem (wastewater-irrigated)2017Basis not stated	mean.
Maize grainEl-Hassanin et al. 2020	Wadi El-Natron (fresh or ground water)2017Basis not stated	mean.
Maize grainIbrahim et al. 2024	Maize-eating households, Jigawa, Nigeria2023Basis not stated	median.
Maize grainJiang et al. 2020	Village 2.5 km from battery plant2018Basis not stated	mean.Same samples: 40–150 µg/kg (range)
Maize grainJiang et al. 2020	Village 2.5 km from battery plant2018Basis not stated	range.
Maize grainMustapha et al. 2024	Hybrid maize, Central market, BauchiCollection date unreportedBasis not stated	mean.
Maize grainMustapha et al. 2024	Hybrid maize, Muda Lawal market, BauchiCollection date unreportedBasis not stated	mean.
Maize grainMustapha et al. 2024	Syria maize, Central market, BauchiCollection date unreportedBasis not stated	mean.
Maize grainMustapha et al. 2024	Syria maize, Muda Lawal market, BauchiCollection date unreportedBasis not stated	mean.
Maize grainRomán-Ochoa et al. 2021	Arequipa growing districts, Peru2019Basis not stated	mean.
Maize grainRubio et al. 2023	Madeira markets, PortugalCollection date unreportedBasis not stated	mean.
Maize grainZhu et al. 2024	Shanghai supermarkets and markets2021–2022Basis not stated	mean.Same samples: 4–10 µg/kg (range)
Maize grainZhu et al. 2024	Shanghai supermarkets and markets2021–2022Basis not stated	range.
5 findings · 3 studies
Sweet or fresh corn, raw or frozenWHO GEMS/Food	EURO, random2003–2019As sold / fresh	median.
Sweet or fresh corn, raw or frozenWHO GEMS/Food	EURO, sampling unstated2011–2013As sold / fresh	median.
Sweet or fresh corn, raw or frozenWHO GEMS/Food	WPRO, random2004–2005As sold / fresh	median.
Sweet or fresh corn, raw or frozenAgarwal et al. 2022	Dhapa waste-dumping ground, Kolkata2016–2017Dry weight	range.
Sweet or fresh corn, raw or frozenSaleem et al. 2025	Grand Forks farmers’ market, USCollection date unreportedDry weight	mean.
6 findings · 3 studies
Sweet corn, cooked as eatenWHO GEMS/Food	EURO, random2010–2012As sold / fresh	median.
Sweet corn, cooked as eatenWHO GEMS/Food	PAHO, random2003–2016As sold / fresh	median.
Sweet corn, cooked as eatenWHO GEMS/Food	WPRO, random2014As sold / fresh	median.
Sweet corn, cooked as eatenWHO GEMS/Food	WPRO, targeted2008As sold / fresh	median.
Sweet corn, cooked as eatenFDA Total Diet Study	United States, four regions2017–2020As sold / fresh	median.
Sweet corn, cooked as eatenMasite et al. 2022	Limpopo produce markets, South Africa2019Dry weight	not detected.
1 finding · 1 study
Sweet corn, pack not statedWHO GEMS/Food	PAHO, random1999–2018As sold / fresh	median.
4 findings · 1 study
Corn, cooked, form not statedWHO GEMS/Food	AFRO, random2018As sold / fresh	median.
Corn, cooked, form not statedWHO GEMS/Food	EURO, random2007–2017As sold / fresh	median.
Corn, cooked, form not statedWHO GEMS/Food	PAHO, random2011–2017As sold / fresh	median.
Corn, cooked, form not statedWHO GEMS/Food	WPRO, random2010–2011As sold / fresh	median.
2 findings · 2 studies
Corn, form not statedRomero-Crespo et al. 2023	Gold-mining orchard, Ecuador2021As sold / fresh	sample value.
Corn, form not statedAltunay et al. 2023	Sivas greengrocer, TürkiyeCollection date unreportedBasis not stated	mean.

43 findings · 14 studies · 11 spread figures folded in
Maize grainWHO GEMS/Food	EURO, random2007–2023As sold / fresh	median.
Maize grainWHO GEMS/Food	EURO, sampling unstated2006–2022As sold / fresh	median.
Maize grainWHO GEMS/Food	European Union, random2000–2014As sold / fresh	median.
Maize grainWHO GEMS/Food	European Union, targeted2009–2010As sold / fresh	median.
Maize grainWHO GEMS/Food	European Union, sampling unstated2002–2012As sold / fresh	median.
Maize grainWHO GEMS/Food	WPRO, random2004–2005As sold / fresh	median.
Maize grainWHO GEMS/Food	WPRO, targeted2001As sold / fresh	median.
Maize grainEdirisinghe et al. 2019	North Central Province farms, Sri Lanka2016As sold / fresh	mean.Same samples: up to 476 µg/kg (range; minimum not quantified)
Maize grainEdirisinghe et al. 2019	North Central Province farms, Sri Lanka2016As sold / fresh	below LOD.
Maize grainEdirisinghe et al. 2019	North Central Province farms, Sri Lanka2016As sold / fresh	range.
Maize grainIslam et al. 2015	Bogra district, Bangladesh2012As sold / fresh	mean.
Maize grainIslam et al. 2015	Bogra district, Bangladesh2012As sold / fresh	range.
Maize grainAbatemi-Usman et al. 2023	Farm 2.7 km upwind of cement plant2017Dry weight	median.
Maize grainAbatemi-Usman et al. 2023	Farm 2.7 km upwind of cement plant2017Dry weight	mean.Same samples: up to 40 µg/kg (range; minimum not quantified)
Maize grainAbatemi-Usman et al. 2023	Farm 2.7 km upwind of cement plant2017Dry weight	range.
Maize grainAbatemi-Usman et al. 2023	Farm 0.7 km downwind of cement plant2017Dry weight	median.
Maize grainAbatemi-Usman et al. 2023	Farm 0.7 km downwind of cement plant2017Dry weight	mean.Same samples: up to 30 µg/kg (range; minimum not quantified)
Maize grainAbatemi-Usman et al. 2023	Farm 0.7 km downwind of cement plant2017Dry weight	range.
Maize grainAbatemi-Usman et al. 2023	Farm 3.1 km downwind of cement plant2017Dry weight	median.
Maize grainAbatemi-Usman et al. 2023	Farm 3.1 km downwind of cement plant2017Dry weight	mean.Same samples: up to 10 µg/kg (range; minimum not quantified)
Maize grainAbatemi-Usman et al. 2023	Farm 3.1 km downwind of cement plant2017Dry weight	range.
Maize grainAbatemi-Usman et al. 2023	Farm 2.3 km downwind of cement plant2017Dry weight	median.
Maize grainAbatemi-Usman et al. 2023	Farm 2.3 km downwind of cement plant2017Dry weight	mean.Same samples: up to 30 µg/kg (range; minimum not quantified)
Maize grainAbatemi-Usman et al. 2023	Farm 2.3 km downwind of cement plant2017Dry weight	range.
Maize grainAbatemi-Usman et al. 2023	Control farm, 18 km upwind of cement plant2017Dry weight	median.
Maize grainAbatemi-Usman et al. 2023	Control farm, 18 km upwind of cement plant2017Dry weight	mean.Same samples: up to 30 µg/kg (range; minimum not quantified)
Maize grainAbatemi-Usman et al. 2023	Control farm, 18 km upwind of cement plant2017Dry weight	range.
Maize grainBai et al. 2022	Ziyang coal-burning area, ShaanxiCollection date unreportedDry weight	mean.
Maize grainIslam et al. 2014	Bogra district fields, Bangladesh2012Dry weight	mean.Same samples: 80–1,700 µg/kg (range)
Maize grainIslam et al. 2014	Bogra district fields, Bangladesh2012Dry weight	range.
Maize grainLiu et al. 2022	Shifang area fields near ChengduCollection date unreportedDry weight	mean.Same samples: 40–130 µg/kg (range)
Maize grainLiu et al. 2022	Shifang area fields near ChengduCollection date unreportedDry weight	range.
Maize grainLiu et al. 2025	Nanyang Basin fields, HenanCollection date unreportedDry weight	mean.Same samples: up to 26 µg/kg (range; minimum not quantified)
Maize grainLiu et al. 2025	Nanyang Basin fields, HenanCollection date unreportedDry weight	range.
Maize grainZhang et al. 2026	Manganese mining and smelting area2020Dry weight	mean.
Maize grainBedoya-Perales et al. 2023	Carumas district, Moquegua2021Basis not stated	median.
Maize grainBedoya-Perales et al. 2023	Chojata district, Moquegua2021Basis not stated	median.
Maize grainBedoya-Perales et al. 2023	Matalaque district, Moquegua2021Basis not stated	median.
Maize grainGholami et al. 2025	All samples 2022 (abstract)2022Basis not stated	mean.
Maize grainGholami et al. 2025	All samples 20222022Basis not stated	mean.
Maize grainGholami et al. 2025	Behbahan Autumn 20222022Basis not stated	mean.
Maize grainGholami et al. 2025	Behbahan both seasons 20222022Basis not stated	mean.
Maize grainGholami et al. 2025	Behbahan Summer 20222022Basis not stated	mean.
Maize grainGholami et al. 2025	Both cities Autumn 20222022Basis not stated	mean.
Maize grainGholami et al. 2025	Both cities Summer 20222022Basis not stated	mean.
Maize grainGholami et al. 2025	Dezfoul Autumn 20222022Basis not stated	mean.
Maize grainGholami et al. 2025	Dezfoul Summer 20222022Basis not stated	mean.
Maize grainGholami et al. 2025	Dezful both seasons 20222022Basis not stated	mean.
Maize grainGholami et al. 2025	Seasonal means span (discussion)2022Basis not stated	range.
Maize grainJiang et al. 2020	Village 2.5 km from battery plant2018Basis not stated	mean.Same samples: 70–160 µg/kg (range)
Maize grainJiang et al. 2020	Village 2.5 km from battery plant2018Basis not stated	range.
Maize grainRomán-Ochoa et al. 2021	Arequipa growing districts, Peru2019Basis not stated	mean.
Maize grainZhu et al. 2024	Shanghai supermarkets and markets2021–2022Basis not stated	mean.Same samples: 4–24 µg/kg (range)
Maize grainZhu et al. 2024	Shanghai supermarkets and markets2021–2022Basis not stated	range.
6 findings · 2 studies
Sweet or fresh corn, raw or frozenWHO GEMS/Food	EURO, random2009–2023As sold / fresh	median.
Sweet or fresh corn, raw or frozenWHO GEMS/Food	EURO, sampling unstated2013As sold / fresh	median.
Sweet or fresh corn, raw or frozenWHO GEMS/Food	European Union, random2009–2014As sold / fresh	median.
Sweet or fresh corn, raw or frozenWHO GEMS/Food	European Union, sampling unstated2002–2011As sold / fresh	median.
Sweet or fresh corn, raw or frozenWHO GEMS/Food	WPRO, random2005–2013As sold / fresh	median.
Sweet or fresh corn, raw or frozenSaleem et al. 2025	Grand Forks farmers’ market, USCollection date unreportedDry weight	mean.
7 findings · 3 studies
Sweet corn, cooked as eatenWHO GEMS/Food	EURO, random2012As sold / fresh	median.
Sweet corn, cooked as eatenWHO GEMS/Food	European Union, random2012As sold / fresh	median.
Sweet corn, cooked as eatenWHO GEMS/Food	European Union, sampling unstated2002–2003As sold / fresh	median.
Sweet corn, cooked as eatenWHO GEMS/Food	WPRO, random2014As sold / fresh	median.
Sweet corn, cooked as eatenWHO GEMS/Food	WPRO, targeted2008As sold / fresh	median.
Sweet corn, cooked as eatenFDA Total Diet Study	United States, four regions2017–2020As sold / fresh	median.
Sweet corn, cooked as eatenMasite et al. 2022	Limpopo produce markets, South Africa2019Dry weight	mean.
1 finding · 1 study
Sweet corn, pack not statedWHO GEMS/Food	EURO, random2019–2023As sold / fresh	median.
2 findings · 1 study
Baby cornWHO GEMS/Food	EURO, random2022–2023As sold / fresh	median.
Baby cornWHO GEMS/Food	WPRO, random2013As sold / fresh	median.
3 findings · 1 study
Corn, cooked, form not statedWHO GEMS/Food	AFRO, random2018As sold / fresh	median.
Corn, cooked, form not statedWHO GEMS/Food	EURO, random2022As sold / fresh	median.
Corn, cooked, form not statedWHO GEMS/Food	European Union, random2007–2009As sold / fresh	median.
1 finding · 1 study
Corn, form not statedRomero-Crespo et al. 2023	Gold-mining orchard, Ecuador2021As sold / fresh	sample value.

3 findings · 1 study
Maize grainWHO GEMS/Food	EURO, random2013–2020As sold / fresh	median.
Maize grainWHO GEMS/Food	EURO, targeted2009–2010As sold / fresh	median.
Maize grainWHO GEMS/Food	EURO, sampling unstated2003–2016As sold / fresh	median.
1 finding · 1 study
Corn, cooked, form not statedWHO GEMS/Food	WPRO, random2010–2011As sold / fresh	median.

22 findings · 11 studies · 4 spread figures folded in
Maize grainWHO GEMS/Food	EURO, random2003–2017As sold / fresh	median.
Maize grainWHO GEMS/Food	EURO, targeted2001As sold / fresh	median.
Maize grainWHO GEMS/Food	EURO, sampling unstated2011–2016As sold / fresh	median.
Maize grainWHO GEMS/Food	WPRO, random2005As sold / fresh	median.
Maize grainWHO GEMS/Food	WPRO, targeted2001As sold / fresh	median.
Maize grainLi et al. 2017	Grocery store control, over 55 km away2015As sold / fresh	mean.
Maize grainLi et al. 2017	A1, 1 km from Power Plant A2015As sold / fresh	mean.
Maize grainLi et al. 2017	A2, 3 km from Power Plant A2015As sold / fresh	mean.
Maize grainLi et al. 2017	B1, 1 km from Power Plant B2015As sold / fresh	mean.
Maize grainLi et al. 2017	B2, 3 km from Power Plant B2015As sold / fresh	mean.
Maize grainLi et al. 2017	B3, 5 km from Power Plant B2015As sold / fresh	mean.
Maize grainLi et al. 2017	B4, 10 km from both Power Plants A and B2015As sold / fresh	mean.
Maize grainGu et al. 2019	Binyang and Xingbin fields, Guangxi2015Dry weight	median.Same samples: 0.1–6.4 µg/kg (range)
Maize grainGu et al. 2019	Binyang and Xingbin fields, Guangxi2015Dry weight	range.
Maize grainLiu et al. 2022	Shifang area fields near ChengduCollection date unreportedDry weight	mean.Same samples: 2–20 µg/kg (range)
Maize grainLiu et al. 2022	Shifang area fields near ChengduCollection date unreportedDry weight	range.
Maize grainLiu et al. 2025	Nanyang Basin fields, HenanCollection date unreportedDry weight	mean.Same samples: up to 3.2 µg/kg (range; minimum not quantified)
Maize grainLiu et al. 2025	Nanyang Basin fields, HenanCollection date unreportedDry weight	range.
Maize grainAbdullahi et al. 2024	Dry season 2023, all 10 locations2023Basis not stated	not detected.
Maize grainAbdullahi et al. 2024	Wet season 2022, all 10 locations2022Basis not stated	not detected.
Maize grainIbrahim et al. 2024	Maize-eating households, Jigawa, Nigeria2023Basis not stated	median.
Maize grainJiang et al. 2020	Village 2.5 km from battery plant2018Basis not stated	mean.Same samples: 1–160 µg/kg (range)
Maize grainJiang et al. 2020	Village 2.5 km from battery plant2018Basis not stated	range.
Maize grainRomán-Ochoa et al. 2021	Arequipa growing districts, Peru2019Basis not stated	mean.
Maize grainRubio et al. 2023	Madeira markets, PortugalCollection date unreportedBasis not stated	mean.
Maize grainZhu et al. 2024	Shanghai supermarkets and markets2021–2022Basis not stated	not detected.
4 findings · 3 studies
Sweet or fresh corn, raw or frozenWHO GEMS/Food	EURO, random2004–2016As sold / fresh	median.
Sweet or fresh corn, raw or frozenWHO GEMS/Food	WPRO, random2004–2005As sold / fresh	median.
Sweet or fresh corn, raw or frozenAgarwal et al. 2022	Dhapa waste-dumping ground, Kolkata2016–2017Dry weight	range.
Sweet or fresh corn, raw or frozenSaleem et al. 2025	Grand Forks farmers’ market, USCollection date unreportedDry weight	mean.
3 findings · 2 studies
Sweet corn, cooked as eatenWHO GEMS/Food	WPRO, random2014As sold / fresh	median.
Sweet corn, cooked as eatenWHO GEMS/Food	WPRO, targeted2008As sold / fresh	median.
Sweet corn, cooked as eatenFDA Total Diet Study	United States, four regions2017–2020As sold / fresh	median.
2 findings · 1 study
Corn, cooked, form not statedWHO GEMS/Food	AFRO, random2018As sold / fresh	median.
Corn, cooked, form not statedWHO GEMS/Food	EURO, random2007–2009As sold / fresh	median.

48 findings · 9 studies · 15 spread figures folded in
Maize grainIslam et al. 2015	Bogra district, Bangladesh2012As sold / fresh	mean.
Maize grainIslam et al. 2015	Bogra district, Bangladesh2012As sold / fresh	range.
Maize grainAbatemi-Usman et al. 2023	Farm 2.7 km upwind of cement plant2017Dry weight	median.
Maize grainAbatemi-Usman et al. 2023	Farm 2.7 km upwind of cement plant2017Dry weight	mean.Same samples: 1,120–1,860 µg/kg (range)
Maize grainAbatemi-Usman et al. 2023	Farm 2.7 km upwind of cement plant2017Dry weight	range.
Maize grainAbatemi-Usman et al. 2023	Farm 0.7 km downwind of cement plant2017Dry weight	median.
Maize grainAbatemi-Usman et al. 2023	Farm 0.7 km downwind of cement plant2017Dry weight	mean.Same samples: 1,060–3,050 µg/kg (range)
Maize grainAbatemi-Usman et al. 2023	Farm 0.7 km downwind of cement plant2017Dry weight	range.
Maize grainAbatemi-Usman et al. 2023	Farm 3.1 km downwind of cement plant2017Dry weight	median.
Maize grainAbatemi-Usman et al. 2023	Farm 3.1 km downwind of cement plant2017Dry weight	mean.Same samples: 1,100–2,280 µg/kg (range)
Maize grainAbatemi-Usman et al. 2023	Farm 3.1 km downwind of cement plant2017Dry weight	range.
Maize grainAbatemi-Usman et al. 2023	Farm 2.3 km downwind of cement plant2017Dry weight	median.
Maize grainAbatemi-Usman et al. 2023	Farm 2.3 km downwind of cement plant2017Dry weight	mean.Same samples: 1,300–2,690 µg/kg (range)
Maize grainAbatemi-Usman et al. 2023	Farm 2.3 km downwind of cement plant2017Dry weight	range.
Maize grainAbatemi-Usman et al. 2023	Control farm, 18 km upwind of cement plant2017Dry weight	median.
Maize grainAbatemi-Usman et al. 2023	Control farm, 18 km upwind of cement plant2017Dry weight	mean.Same samples: 1,270–6,640 µg/kg (range)
Maize grainAbatemi-Usman et al. 2023	Control farm, 18 km upwind of cement plant2017Dry weight	range.
Maize grainIslam et al. 2014	Bogra district fields, Bangladesh2012Dry weight	mean.Same samples: 240–2,800 µg/kg (range)
Maize grainIslam et al. 2014	Bogra district fields, Bangladesh2012Dry weight	range.
Maize grainPirsaheb et al. 2015	Kermanshah retail, Iran2014Dry weight	mean.
Maize grainPirsaheb et al. 2015	Kermanshah retail, Iran2014Dry weight	not detected.
Maize grainZhang et al. 2026	Manganese mining and smelting area2020Dry weight	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, all 10 locations2023Basis not stated	mean.Same samples: 1,150–1,610 µg/kg (range)
Maize grainAbdullahi et al. 2024	Dry season 2023, all 10 locations2023Basis not stated	range.
Maize grainAbdullahi et al. 2024	Dry season 2023, Bulan Wanzamai2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Gafan2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Gafan Bunkure2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Gafan II2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Imawa (Gada Mailotso)2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Imawa (Rimin Kwarya)2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Kukoki2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Kura (Babbar Gada)2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Kura (Fegin Malu)2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Kwalele2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Wet season 2022, all 10 locations2022Basis not stated	mean.Same samples: 180–620 µg/kg (range)
Maize grainAbdullahi et al. 2024	Wet season 2022, all 10 locations2022Basis not stated	range.
Maize grainAbdullahi et al. 2024	Wet season 2022, Dakasoye2022Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Wet season 2022, Gafan2022Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Wet season 2022, Imawa I2022Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Wet season 2022, Imawa II2022Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Wet season 2022, Kura (Gorubawa)2022Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Wet season 2022, Kura (Tsauni)2022Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Wet season 2022, Makuntiri2022Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Wet season 2022, Rigada2022Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Wet season 2022, Yadakwari2022Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Wet season 2022, Yantomo2022Basis not stated	mean.
Maize grainBazie et al. 2022	Bobo Dioulasso2020Basis not stated	median.Same samples: up to 1,860 µg/kg (range; minimum not quantified)
Maize grainBazie et al. 2022	Bobo Dioulasso2020Basis not stated	range.
Maize grainBazie et al. 2022	Cinkasse2020Basis not stated	median.Same samples: 320–1,860 µg/kg (range)
Maize grainBazie et al. 2022	Cinkasse2020Basis not stated	range.
Maize grainBazie et al. 2022	Dakola2020Basis not stated	median.Same samples: 590–1,420 µg/kg (range)
Maize grainBazie et al. 2022	Dakola2020Basis not stated	range.
Maize grainBazie et al. 2022	Niankologo2020Basis not stated	median.Same samples: 470–1,730 µg/kg (range)
Maize grainBazie et al. 2022	Niankologo2020Basis not stated	range.
Maize grainBazie et al. 2022	Ouagadougou2020Basis not stated	median.Same samples: 140–1,040 µg/kg (range)
Maize grainBazie et al. 2022	Ouagadougou2020Basis not stated	range.
Maize grainBazie et al. 2022	Total (all maize samples)2020Basis not stated	median.Same samples: up to 1,860 µg/kg (range; minimum not quantified)
Maize grainBazie et al. 2022	Total (all maize samples)2020Basis not stated	range.
Maize grainBedoya-Perales et al. 2023	Carumas district, Moquegua2021Basis not stated	median.
Maize grainBedoya-Perales et al. 2023	Chojata district, Moquegua2021Basis not stated	median.
Maize grainBedoya-Perales et al. 2023	Matalaque district, Moquegua2021Basis not stated	median.
Maize grainJiang et al. 2020	Village 2.5 km from battery plant2018Basis not stated	mean.Same samples: 400–1,120 µg/kg (range)
Maize grainJiang et al. 2020	Village 2.5 km from battery plant2018Basis not stated	range.
1 finding · 1 study
Sweet or fresh corn, raw or frozenSaleem et al. 2025	Grand Forks farmers’ market, USCollection date unreportedDry weight	mean.
2 findings · 2 studies
Sweet corn, cooked as eatenFDA Total Diet Study	United States, four regions2017–2020As sold / fresh	median.
Sweet corn, cooked as eatenMasite et al. 2022	Limpopo produce markets, South Africa2019Dry weight	not detected.
1 finding · 1 study
Corn, form not statedRomero-Crespo et al. 2023	Gold-mining orchard, Ecuador2021As sold / fresh	sample value.

56 findings · 14 studies · 16 spread figures folded in
Maize grainIslam et al. 2015	Bogra district, Bangladesh2012As sold / fresh	mean.
Maize grainIslam et al. 2015	Bogra district, Bangladesh2012As sold / fresh	range.
Maize grainAbatemi-Usman et al. 2023	Farm 2.7 km upwind of cement plant2017Dry weight	median.
Maize grainAbatemi-Usman et al. 2023	Farm 2.7 km upwind of cement plant2017Dry weight	mean.Same samples: 1,850–2,990 µg/kg (range)
Maize grainAbatemi-Usman et al. 2023	Farm 2.7 km upwind of cement plant2017Dry weight	range.
Maize grainAbatemi-Usman et al. 2023	Farm 0.7 km downwind of cement plant2017Dry weight	median.
Maize grainAbatemi-Usman et al. 2023	Farm 0.7 km downwind of cement plant2017Dry weight	mean.Same samples: 1,630–6,140 µg/kg (range)
Maize grainAbatemi-Usman et al. 2023	Farm 0.7 km downwind of cement plant2017Dry weight	range.
Maize grainAbatemi-Usman et al. 2023	Farm 3.1 km downwind of cement plant2017Dry weight	median.
Maize grainAbatemi-Usman et al. 2023	Farm 3.1 km downwind of cement plant2017Dry weight	mean.Same samples: 1,750–3,570 µg/kg (range)
Maize grainAbatemi-Usman et al. 2023	Farm 3.1 km downwind of cement plant2017Dry weight	range.
Maize grainAbatemi-Usman et al. 2023	Farm 2.3 km downwind of cement plant2017Dry weight	median.
Maize grainAbatemi-Usman et al. 2023	Farm 2.3 km downwind of cement plant2017Dry weight	mean.Same samples: 1,830–3,950 µg/kg (range)
Maize grainAbatemi-Usman et al. 2023	Farm 2.3 km downwind of cement plant2017Dry weight	range.
Maize grainAbatemi-Usman et al. 2023	Control farm, 18 km upwind of cement plant2017Dry weight	median.
Maize grainAbatemi-Usman et al. 2023	Control farm, 18 km upwind of cement plant2017Dry weight	mean.Same samples: 1,980–14,300 µg/kg (range)
Maize grainAbatemi-Usman et al. 2023	Control farm, 18 km upwind of cement plant2017Dry weight	range.
Maize grainGetu et al. 2022	Debre Markos market, Ethiopia2020Dry weight	mean.
Maize grainIslam et al. 2014	Bogra district fields, Bangladesh2012Dry weight	mean.Same samples: 390–4,000 µg/kg (range)
Maize grainIslam et al. 2014	Bogra district fields, Bangladesh2012Dry weight	range.
Maize grainLiu et al. 2025	Nanyang Basin fields, HenanCollection date unreportedDry weight	mean.Same samples: up to 829 µg/kg (range; minimum not quantified)
Maize grainLiu et al. 2025	Nanyang Basin fields, HenanCollection date unreportedDry weight	range.
Maize grainPirsaheb et al. 2015	Kermanshah retail, Iran2014Dry weight	mean.Same samples: 287 µg/kg (minimum)
Maize grainPirsaheb et al. 2015	Kermanshah retail, Iran2014Dry weight	min.
Maize grainZhang et al. 2026	Manganese mining and smelting area2020Dry weight	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, all 10 locations2023Basis not stated	mean.Same samples: 1,750–4,630 µg/kg (range)
Maize grainAbdullahi et al. 2024	Dry season 2023, all 10 locations2023Basis not stated	range.
Maize grainAbdullahi et al. 2024	Dry season 2023, Bulan Wanzamai2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Gafan2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Gafan Bunkure2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Gafan II2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Imawa (Gada Mailotso)2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Imawa (Rimin Kwarya)2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Kukoki2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Kura (Babbar Gada)2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Kura (Fegin Malu)2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Dry season 2023, Kwalele2023Basis not stated	mean.
Maize grainAbdullahi et al. 2024	Wet season 2022, all 10 locations2022Basis not stated	not detected.
Maize grainBazie et al. 2022	Bobo Dioulasso2020Basis not stated	median.Same samples: up to 300 µg/kg (range; minimum not quantified)
Maize grainBazie et al. 2022	Bobo Dioulasso2020Basis not stated	range.
Maize grainBazie et al. 2022	Cinkasse2020Basis not stated	median.Same samples: up to 300 µg/kg (range; minimum not quantified)
Maize grainBazie et al. 2022	Cinkasse2020Basis not stated	range.
Maize grainBazie et al. 2022	Dakola2020Basis not stated	median.Same samples: up to 140 µg/kg (range; minimum not quantified)
Maize grainBazie et al. 2022	Dakola2020Basis not stated	range.
Maize grainBazie et al. 2022	Niankologo2020Basis not stated	median.Same samples: up to 220 µg/kg (range; minimum not quantified)
Maize grainBazie et al. 2022	Niankologo2020Basis not stated	range.
Maize grainBazie et al. 2022	Ouagadougou2020Basis not stated	median.Same samples: 20–150 µg/kg (range)
Maize grainBazie et al. 2022	Ouagadougou2020Basis not stated	range.
Maize grainBazie et al. 2022	Total (all maize samples)2020Basis not stated	median.Same samples: up to 300 µg/kg (range; minimum not quantified)
Maize grainBazie et al. 2022	Total (all maize samples)2020Basis not stated	range.
Maize grainBedoya-Perales et al. 2023	Carumas district, Moquegua2021Basis not stated	median.
Maize grainBedoya-Perales et al. 2023	Chojata district, Moquegua2021Basis not stated	median.
Maize grainBedoya-Perales et al. 2023	Matalaque district, Moquegua2021Basis not stated	median.
Maize grainGholami et al. 2025	All samples 2022 (abstract)2022Basis not stated	mean.
Maize grainGholami et al. 2025	All samples 20222022Basis not stated	mean.
Maize grainGholami et al. 2025	Behbahan Autumn 20222022Basis not stated	mean.
Maize grainGholami et al. 2025	Behbahan both seasons 20222022Basis not stated	mean.
Maize grainGholami et al. 2025	Behbahan Summer 20222022Basis not stated	mean.
Maize grainGholami et al. 2025	Both cities Autumn 20222022Basis not stated	mean.
Maize grainGholami et al. 2025	Both cities Summer 20222022Basis not stated	mean.
Maize grainGholami et al. 2025	Dezfoul Autumn 20222022Basis not stated	mean.
Maize grainGholami et al. 2025	Dezfoul Summer 20222022Basis not stated	mean.
Maize grainGholami et al. 2025	Dezful both seasons 20222022Basis not stated	mean.
Maize grainGholami et al. 2025	Seasonal means span (discussion)2022Basis not stated	range.
Maize grainJiang et al. 2020	Village 2.5 km from battery plant2018Basis not stated	mean.Same samples: 150–750 µg/kg (range)
Maize grainJiang et al. 2020	Village 2.5 km from battery plant2018Basis not stated	range.
Maize grainMustapha et al. 2024	Hybrid maize, Central market, BauchiCollection date unreportedBasis not stated	not detected.
Maize grainMustapha et al. 2024	Hybrid maize, Muda Lawal market, BauchiCollection date unreportedBasis not stated	not detected.
Maize grainMustapha et al. 2024	Syria maize, Central market, BauchiCollection date unreportedBasis not stated	mean.
Maize grainMustapha et al. 2024	Syria maize, Muda Lawal market, BauchiCollection date unreportedBasis not stated	mean.
Maize grainZhu et al. 2024	Shanghai supermarkets and markets2021–2022Basis not stated	mean.
Maize grainZhu et al. 2024	Shanghai supermarkets and markets2021–2022Basis not stated	range.
2 findings · 2 studies
Sweet or fresh corn, raw or frozenAgarwal et al. 2022	Dhapa waste-dumping ground, Kolkata2016–2017Dry weight	range.
Sweet or fresh corn, raw or frozenSaleem et al. 2025	Grand Forks farmers’ market, USCollection date unreportedDry weight	mean.
2 findings · 2 studies
Sweet corn, cooked as eatenFDA Total Diet Study	United States, four regions2017–2020As sold / fresh	median.
Sweet corn, cooked as eatenMasite et al. 2022	Limpopo produce markets, South Africa2019Dry weight	not detected.
1 finding · 1 study
Corn, form not statedRomero-Crespo et al. 2023	Gold-mining orchard, Ecuador2021As sold / fresh	below LOD.

3 findings · 1 study
Maize grainBedoya-Perales et al. 2023	Carumas district, Moquegua2021Basis not stated	median.
Maize grainBedoya-Perales et al. 2023	Chojata district, Moquegua2021Basis not stated	median.
Maize grainBedoya-Perales et al. 2023	Matalaque district, Moquegua2021Basis not stated	median.
1 finding · 1 study
Corn, cooked, form not statedWHO GEMS/Food	EURO, random2007–2009As sold / fresh	median.

6 findings · 3 studies
Maize grainWHO GEMS/Food	WPRO, random2005As sold / fresh	median.
Maize grainWHO GEMS/Food	WPRO, targeted2001As sold / fresh	median.
Maize grainBedoya-Perales et al. 2023	Carumas district, Moquegua2021Basis not stated	median.
Maize grainBedoya-Perales et al. 2023	Chojata district, Moquegua2021Basis not stated	median.
Maize grainBedoya-Perales et al. 2023	Matalaque district, Moquegua2021Basis not stated	median.
Maize grainRomán-Ochoa et al. 2021	Arequipa growing districts, Peru2019Basis not stated	mean.
1 finding · 1 study
Sweet or fresh corn, raw or frozenWHO GEMS/Food	WPRO, random2005As sold / fresh	median.
2 findings · 1 study
Corn, cooked, form not statedWHO GEMS/Food	EURO, random2007–2009As sold / fresh	median.
Corn, cooked, form not statedWHO GEMS/Food	WPRO, random2010–2011As sold / fresh	median.

3 findings · 1 study
Maize grainBedoya-Perales et al. 2023	Carumas district, Moquegua2021Basis not stated	median.
Maize grainBedoya-Perales et al. 2023	Chojata district, Moquegua2021Basis not stated	median.
Maize grainBedoya-Perales et al. 2023	Matalaque district, Moquegua2021Basis not stated	median.
1 finding · 1 study
Sweet corn, cooked as eatenFDA Total Diet Study	United States, four regions2017–2020As sold / fresh	median.

Shared dataset methods and interpretation

Source summaries retain their original statistic, material, basis and censoring. Each source drawer identifies methods and overlapping samples. No matched reference or pooled distribution is inferred.

HMI corn Pb reference · Maize grain

Reference and scope

HMI corn Pb reference · Maize grain. Maize grain; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	≤15	≤26.4	13–50 (bounded)
Alternative weighting	≤15	≤26.4	13–50 (bounded)

37 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	37	100%

Methods

HMI pools subgroup medians for maize grain on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

GEMS/Food is the only compatible sampling family for maize grain on this basis in the completed corn ledger, so this single-family reference cannot represent other markets. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

WHO GEMS/Food

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-grain-fw-Pb:a59995895459

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn Pb reference · Maize grain, dry weight

Reference and scope

HMI corn Pb reference · Maize grain, dry weight. Maize grain; Dry weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	≤1	10–10.5 (bounded)	20
Alternative weighting	≤1	10–10.5 (bounded)	20

2 reference units; 2 sampling families. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	1	50%
Abatemi-Usman et al. 2023	1	50%

Methods

HMI pools subgroup medians for maize grain on a dry weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year, and printed subgroup medians from ordinary fields or markets in the literature. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

2 sampling families with different designs; none is a probability sample of world supply. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-grain-dw-Pb:28587d1e6c2a

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn Pb reference · Sweet or fresh corn, raw or frozen

Reference and scope

HMI corn Pb reference · Sweet or fresh corn, raw or frozen. Sweet or fresh corn, raw or frozen; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	≤5	≤8	≤18
Alternative weighting	≤5	≤8	≤18

26 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	26	100%

Methods

HMI pools subgroup medians for sweet or fresh corn, raw or frozen on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

GEMS/Food is the only compatible sampling family for sweet or fresh corn, raw or frozen on this basis in the completed corn ledger, so this single-family reference cannot represent other markets. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

WHO GEMS/Food

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-sweet-fw-Pb:35c6b55c6827

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn Pb reference · Sweet corn, cooked as eaten

Reference and scope

HMI corn Pb reference · Sweet corn, cooked as eaten. Sweet corn, cooked as eaten; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	≤4	≤4	≤7
Alternative weighting	≤4	≤4	≤7

48 reference units; 2 sampling families. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	21	50%
FDA Total Diet Study	27	50%

Methods

HMI pools subgroup medians for sweet corn, cooked as eaten on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year, and each FDA Total Diet Study national composite of frozen corn boiled as eaten. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

2 sampling families with different designs; none is a probability sample of world supply. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-sweet_cooked-fw-Pb:dcdb3a604391

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn Pb reference · Sweet corn, pack not stated

Reference and scope

HMI corn Pb reference · Sweet corn, pack not stated. Sweet corn, pack not stated; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	1.94	2.71	3.25
Alternative weighting	1.94	2.71	3.25

12 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	12	100%

Methods

HMI pools subgroup medians for sweet corn, pack not stated on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

GEMS/Food is the only compatible sampling family for sweet corn, pack not stated on this basis in the completed corn ledger, so this single-family reference cannot represent other markets. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

WHO GEMS/Food

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-sweet_unstated-fw-Pb:c8bd3b10742c

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn Pb reference · Baby corn

Reference and scope

HMI corn Pb reference · Baby corn. Baby corn; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	≤1.75	0.55–3.7 (bounded)	50.5–65 (bounded)
Alternative weighting	≤1.75	0.55–3.7 (bounded)	50.5–65 (bounded)

4 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	4	100%

Methods

HMI pools subgroup medians for baby corn on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

GEMS/Food is the only compatible sampling family for baby corn on this basis in the completed corn ledger, so this single-family reference cannot represent other markets. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

WHO GEMS/Food

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-baby-fw-Pb:554527b7501b

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn Pb reference · Corn, cooked, form not stated

Reference and scope

HMI corn Pb reference · Corn, cooked, form not stated. Corn, cooked, form not stated; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	≤2	≤2.5	6–6.95 (bounded)
Alternative weighting	≤2	≤2.5	6–6.95 (bounded)

7 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	7	100%

Methods

HMI pools subgroup medians for corn, cooked, form not stated on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

GEMS/Food is the only compatible sampling family for corn, cooked, form not stated on this basis in the completed corn ledger, so this single-family reference cannot represent other markets. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

WHO GEMS/Food

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-cooked_unstated-fw-Pb:db7576d1658a

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn Cd reference · Maize grain

Reference and scope

HMI corn Cd reference · Maize grain. Maize grain; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	≤3.2	4.88	4.88
Alternative weighting	≤3.2	4.88	4.88

36 reference units; 2 sampling families. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	35	50%
Edirisinghe et al. 2019	1	50%

Methods

HMI pools subgroup medians for maize grain on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year, and printed subgroup medians from ordinary fields or markets in the literature. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

2 sampling families with different designs; none is a probability sample of world supply. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-grain-fw-Cd:15b06e133080

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn Cd reference · Maize grain, dry weight

Reference and scope

HMI corn Cd reference · Maize grain, dry weight. Maize grain; Dry weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	220	220	220
Alternative weighting	220	220	220

1 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	1	100%

Methods

HMI pools subgroup medians for maize grain on a dry weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

GEMS/Food is the only compatible sampling family for maize grain on this basis in the completed corn ledger, so this single-family reference cannot represent other markets. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

WHO GEMS/Food

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-grain-dw-Cd:b5fb0341bf0a

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn Cd reference · Sweet or fresh corn, raw or frozen

Reference and scope

HMI corn Cd reference · Sweet or fresh corn, raw or frozen. Sweet or fresh corn, raw or frozen; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	≤1.7	≤4	1.75–7.5 (bounded)
Alternative weighting	≤1.7	≤4	1.75–7.5 (bounded)

20 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	20	100%

Methods

HMI pools subgroup medians for sweet or fresh corn, raw or frozen on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

GEMS/Food is the only compatible sampling family for sweet or fresh corn, raw or frozen on this basis in the completed corn ledger, so this single-family reference cannot represent other markets. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

WHO GEMS/Food

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-sweet-fw-Cd:d2fd6cd259dc

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn Cd reference · Sweet corn, cooked as eaten

Reference and scope

HMI corn Cd reference · Sweet corn, cooked as eaten. Sweet corn, cooked as eaten; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	1.4–2 (bounded)	2.5–2.6 (bounded)	3
Alternative weighting	1.6–2 (bounded)	2.5–2.6 (bounded)	3

41 reference units; 2 sampling families. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	14	50%
FDA Total Diet Study	27	50%

Methods

HMI pools subgroup medians for sweet corn, cooked as eaten on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year, and each FDA Total Diet Study national composite of frozen corn boiled as eaten. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

2 sampling families with different designs; none is a probability sample of world supply. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-sweet_cooked-fw-Cd:923bf0be660c

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn Cd reference · Sweet corn, pack not stated

Reference and scope

HMI corn Cd reference · Sweet corn, pack not stated. Sweet corn, pack not stated; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	1.7–1.72 (bounded)	2.2	2.58–2.79 (bounded)
Alternative weighting	1.7–1.72 (bounded)	2.2	2.58–2.79 (bounded)

17 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	17	100%

Methods

HMI pools subgroup medians for sweet corn, pack not stated on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

GEMS/Food is the only compatible sampling family for sweet corn, pack not stated on this basis in the completed corn ledger, so this single-family reference cannot represent other markets. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

WHO GEMS/Food

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-sweet_unstated-fw-Cd:7ddb17782e45

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn Cd reference · Corn, cooked, form not stated

Reference and scope

HMI corn Cd reference · Corn, cooked, form not stated. Corn, cooked, form not stated; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	1–2 (bounded)	2.5–2.6 (bounded)	3–4 (bounded)
Alternative weighting	1–2 (bounded)	2.5–2.6 (bounded)	3–4 (bounded)

11 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	11	100%

Methods

HMI pools subgroup medians for corn, cooked, form not stated on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

GEMS/Food is the only compatible sampling family for corn, cooked, form not stated on this basis in the completed corn ledger, so this single-family reference cannot represent other markets. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

WHO GEMS/Food

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-cooked_unstated-fw-Cd:82b0938504b1

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn tAs reference · Maize grain

Reference and scope

HMI corn tAs reference · Maize grain. Maize grain; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	≤12	≤17.2	5–44.2 (bounded)
Alternative weighting	≤12	≤17.2	5–44.2 (bounded)

50 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	50	100%

Methods

HMI pools subgroup medians for maize grain on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

GEMS/Food is the only compatible sampling family for maize grain on this basis in the completed corn ledger, so this single-family reference cannot represent other markets. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

WHO GEMS/Food

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-grain-fw-tAs:f98425a498e0

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn tAs reference · Maize grain, dry weight

Reference and scope

HMI corn tAs reference · Maize grain, dry weight. Maize grain; Dry weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	10	10	10
Alternative weighting	10	10	10

1 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
Abatemi-Usman et al. 2023	1	100%

Methods

HMI pools subgroup medians for maize grain on a dry weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year, and printed subgroup medians from ordinary fields or markets in the literature. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

Abatemi-Usman et al. 2023 is the only compatible sampling family for maize grain on this basis in the completed corn ledger, so this single-family reference cannot represent other markets. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

Abatemi-Usman et al. 2023

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-grain-dw-tAs:98e0650cd321

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn tAs reference · Sweet or fresh corn, raw or frozen

Reference and scope

HMI corn tAs reference · Sweet or fresh corn, raw or frozen. Sweet or fresh corn, raw or frozen; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	≤3.75	≤9.5	5.5–19.3 (bounded)
Alternative weighting	≤3.75	≤9.5	5.5–19.3 (bounded)

20 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	20	100%

Methods

HMI pools subgroup medians for sweet or fresh corn, raw or frozen on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

GEMS/Food is the only compatible sampling family for sweet or fresh corn, raw or frozen on this basis in the completed corn ledger, so this single-family reference cannot represent other markets. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

WHO GEMS/Food

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-sweet-fw-tAs:f6242dd19b27

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn tAs reference · Sweet corn, cooked as eaten

Reference and scope

HMI corn tAs reference · Sweet corn, cooked as eaten. Sweet corn, cooked as eaten; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	≤3	≤3.5	≤6.12
Alternative weighting	≤3	≤3.5	≤6.12

33 reference units; 2 sampling families. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	6	50%
FDA Total Diet Study	27	50%

Methods

HMI pools subgroup medians for sweet corn, cooked as eaten on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year, and each FDA Total Diet Study national composite of frozen corn boiled as eaten. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

2 sampling families with different designs; none is a probability sample of world supply. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-sweet_cooked-fw-tAs:7a5015d711e5

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn tAs reference · Sweet corn, pack not stated

Reference and scope

HMI corn tAs reference · Sweet corn, pack not stated. Sweet corn, pack not stated; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	≤1.7	≤1.7	≤20
Alternative weighting	≤1.7	≤1.7	≤20

3 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	3	100%

Methods

HMI pools subgroup medians for sweet corn, pack not stated on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

GEMS/Food is the only compatible sampling family for sweet corn, pack not stated on this basis in the completed corn ledger, so this single-family reference cannot represent other markets. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

WHO GEMS/Food

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-sweet_unstated-fw-tAs:9ebb5bb29e7b

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn tAs reference · Baby corn

Reference and scope

HMI corn tAs reference · Baby corn. Baby corn; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	≤0.3	≤3.5	≤3.5
Alternative weighting	≤0.3	≤3.5	≤3.5

3 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	3	100%

Methods

HMI pools subgroup medians for baby corn on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

GEMS/Food is the only compatible sampling family for baby corn on this basis in the completed corn ledger, so this single-family reference cannot represent other markets. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

WHO GEMS/Food

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-baby-fw-tAs:cd672604c9ff

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn tAs reference · Corn, cooked, form not stated

Reference and scope

HMI corn tAs reference · Corn, cooked, form not stated. Corn, cooked, form not stated; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	≤5	≤10	8.5–11 (bounded)
Alternative weighting	≤5	≤10	8.5–11 (bounded)

5 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	5	100%

Methods

HMI pools subgroup medians for corn, cooked, form not stated on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

GEMS/Food is the only compatible sampling family for corn, cooked, form not stated on this basis in the completed corn ledger, so this single-family reference cannot represent other markets. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

WHO GEMS/Food

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-cooked_unstated-fw-tAs:81084692cdac

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn iAs reference · Maize grain

Reference and scope

HMI corn iAs reference · Maize grain. Maize grain; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	≤7.5	≤10	8–25 (bounded)
Alternative weighting	≤7.5	≤10	8–25 (bounded)

7 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	7	100%

Methods

HMI pools subgroup medians for maize grain on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

GEMS/Food is the only compatible sampling family for maize grain on this basis in the completed corn ledger, so this single-family reference cannot represent other markets. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

WHO GEMS/Food

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-grain-fw-iAs:be2eb09ab3ae

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn iAs reference · Corn, cooked, form not stated

Reference and scope

HMI corn iAs reference · Corn, cooked, form not stated. Corn, cooked, form not stated; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	≤3	≤3	≤3
Alternative weighting	≤3	≤3	≤3

2 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	2	100%

Methods

HMI pools subgroup medians for corn, cooked, form not stated on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

GEMS/Food is the only compatible sampling family for corn, cooked, form not stated on this basis in the completed corn ledger, so this single-family reference cannot represent other markets. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

WHO GEMS/Food

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-cooked_unstated-fw-iAs:cc79df169ac5

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn tHg reference · Maize grain

Reference and scope

HMI corn tHg reference · Maize grain. Maize grain; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	≤0.42	≤1.67	0.37–17 (bounded)
Alternative weighting	≤0.42	≤1.67	0.37–17 (bounded)

19 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	19	100%

Methods

HMI pools subgroup medians for maize grain on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

GEMS/Food is the only compatible sampling family for maize grain on this basis in the completed corn ledger, so this single-family reference cannot represent other markets. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

WHO GEMS/Food

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-grain-fw-tHg:0fdf59acea68

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn tHg reference · Sweet or fresh corn, raw or frozen

Reference and scope

HMI corn tHg reference · Sweet or fresh corn, raw or frozen. Sweet or fresh corn, raw or frozen; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	≤0.3	0.0725–0.397 (bounded)	0.425–1.08 (bounded)
Alternative weighting	≤0.3	0.0725–0.397 (bounded)	0.425–1.08 (bounded)

14 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	14	100%

Methods

HMI pools subgroup medians for sweet or fresh corn, raw or frozen on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

GEMS/Food is the only compatible sampling family for sweet or fresh corn, raw or frozen on this basis in the completed corn ledger, so this single-family reference cannot represent other markets. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

WHO GEMS/Food

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-sweet-fw-tHg:76a9f692a08d

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn tHg reference · Sweet corn, cooked as eaten

Reference and scope

HMI corn tHg reference · Sweet corn, cooked as eaten. Sweet corn, cooked as eaten; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	≤1	≤1.2	0.447–3.2 (bounded)
Alternative weighting	≤1	≤1.2	0.447–3.2 (bounded)

29 reference units; 2 sampling families. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	2	50%
FDA Total Diet Study	27	50%

Methods

HMI pools subgroup medians for sweet corn, cooked as eaten on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year, and each FDA Total Diet Study national composite of frozen corn boiled as eaten. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

2 sampling families with different designs; none is a probability sample of world supply. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-sweet_cooked-fw-tHg:fd2b00b16e07

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn tHg reference · Corn, cooked, form not stated

Reference and scope

HMI corn tHg reference · Corn, cooked, form not stated. Corn, cooked, form not stated; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	≤4.6	≤5	≤5
Alternative weighting	≤4.6	≤5	≤5

4 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	4	100%

Methods

HMI pools subgroup medians for corn, cooked, form not stated on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

GEMS/Food is the only compatible sampling family for corn, cooked, form not stated on this basis in the completed corn ledger, so this single-family reference cannot represent other markets. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

WHO GEMS/Food

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-cooked_unstated-fw-tHg:72639ff96050

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn Ni reference · Maize grain, dry weight

Reference and scope

HMI corn Ni reference · Maize grain, dry weight. Maize grain; Dry weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	1760	1760	1760
Alternative weighting	1760	1760	1760

1 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
Abatemi-Usman et al. 2023	1	100%

Methods

HMI pools subgroup medians for maize grain on a dry weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year, and printed subgroup medians from ordinary fields or markets in the literature. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

Abatemi-Usman et al. 2023 is the only compatible sampling family for maize grain on this basis in the completed corn ledger, so this single-family reference cannot represent other markets. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

Abatemi-Usman et al. 2023

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-grain-dw-Ni:af3b41a5d49f

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn Ni reference · Sweet corn, cooked as eaten

Reference and scope

HMI corn Ni reference · Sweet corn, cooked as eaten. Sweet corn, cooked as eaten; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	≤40	≤40	≤40
Alternative weighting	≤40	≤40	≤40

27 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
FDA Total Diet Study	27	100%

Methods

HMI pools subgroup medians for sweet corn, cooked as eaten on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year, and each FDA Total Diet Study national composite of frozen corn boiled as eaten. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

FDA Total Diet Study is the only compatible sampling family for sweet corn, cooked as eaten on this basis in the completed corn ledger, so this single-family reference cannot represent other markets. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

FDA Total Diet Study

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-sweet_cooked-fw-Ni:cfbc5af13a4a

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn Cr reference · Maize grain, dry weight

Reference and scope

HMI corn Cr reference · Maize grain, dry weight. Maize grain; Dry weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	2580	2580	2580
Alternative weighting	2580	2580	2580

1 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
Abatemi-Usman et al. 2023	1	100%

Methods

HMI pools subgroup medians for maize grain on a dry weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year, and printed subgroup medians from ordinary fields or markets in the literature. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

Abatemi-Usman et al. 2023 is the only compatible sampling family for maize grain on this basis in the completed corn ledger, so this single-family reference cannot represent other markets. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

Abatemi-Usman et al. 2023

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-grain-dw-Cr:64238bb40f2c

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn Cr reference · Sweet corn, cooked as eaten

Reference and scope

HMI corn Cr reference · Sweet corn, cooked as eaten. Sweet corn, cooked as eaten; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	≤50	≤50	≤50
Alternative weighting	≤50	≤50	≤50

27 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
FDA Total Diet Study	27	100%

Methods

HMI pools subgroup medians for sweet corn, cooked as eaten on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year, and each FDA Total Diet Study national composite of frozen corn boiled as eaten. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

FDA Total Diet Study is the only compatible sampling family for sweet corn, cooked as eaten on this basis in the completed corn ledger, so this single-family reference cannot represent other markets. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

FDA Total Diet Study

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-sweet_cooked-fw-Cr:5867ef3c15b7

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn Al reference · Corn, cooked, form not stated

Reference and scope

HMI corn Al reference · Corn, cooked, form not stated. Corn, cooked, form not stated; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	≤236	≤236	≤236
Alternative weighting	≤236	≤236	≤236

3 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	3	100%

Methods

HMI pools subgroup medians for corn, cooked, form not stated on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

GEMS/Food is the only compatible sampling family for corn, cooked, form not stated on this basis in the completed corn ledger, so this single-family reference cannot represent other markets. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

WHO GEMS/Food

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-cooked_unstated-fw-Al:338b28185448

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn Sn reference · Maize grain

Reference and scope

HMI corn Sn reference · Maize grain. Maize grain; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	≤30	50–80 (bounded)	100–130 (bounded)
Alternative weighting	≤30	50–80 (bounded)	100–130 (bounded)

2 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	2	100%

Methods

HMI pools subgroup medians for maize grain on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

GEMS/Food is the only compatible sampling family for maize grain on this basis in the completed corn ledger, so this single-family reference cannot represent other markets. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

WHO GEMS/Food

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-grain-fw-Sn:c7ffc663ff8e

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn Sn reference · Sweet or fresh corn, raw or frozen

Reference and scope

HMI corn Sn reference · Sweet or fresh corn, raw or frozen. Sweet or fresh corn, raw or frozen; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	100–130 (bounded)	100–130 (bounded)	100–130 (bounded)
Alternative weighting	100–130 (bounded)	100–130 (bounded)	100–130 (bounded)

1 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	1	100%

Methods

HMI pools subgroup medians for sweet or fresh corn, raw or frozen on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

GEMS/Food is the only compatible sampling family for sweet or fresh corn, raw or frozen on this basis in the completed corn ledger, so this single-family reference cannot represent other markets. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

WHO GEMS/Food

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-sweet-fw-Sn:dcfffe3aeabc

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn Sn reference · Corn, cooked, form not stated

Reference and scope

HMI corn Sn reference · Corn, cooked, form not stated. Corn, cooked, form not stated; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	34.9	49.4	50.4
Alternative weighting	34.9	49.4	50.4

5 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	5	100%

Methods

HMI pools subgroup medians for corn, cooked, form not stated on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

GEMS/Food is the only compatible sampling family for corn, cooked, form not stated on this basis in the completed corn ledger, so this single-family reference cannot represent other markets. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

WHO GEMS/Food

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-cooked_unstated-fw-Sn:b5b78b8f859b

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

HMI corn U reference · Sweet corn, cooked as eaten

Reference and scope

HMI corn U reference · Sweet corn, cooked as eaten. Sweet corn, cooked as eaten; As sold, as eaten or fresh weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	≤1	≤1	≤1
Alternative weighting	≤1	≤1	≤1

27 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
FDA Total Diet Study	27	100%

Methods

HMI pools subgroup medians for sweet corn, cooked as eaten on a as sold, as eaten or fresh weight basis: individual WHO GEMS/Food results summarized as one median per WHO region, sampling type and collection year, and each FDA Total Diet Study national composite of frozen corn boiled as eaten. Each sampling family has equal total weight. Non-detects stay as zero-to-limit intervals, so quartiles carry lower and upper bounds. Means, ranges and maxima never enter as observations. Other forms of corn, other bases, results without a stated basis and grain from mining-, industry- or wastewater-affected fields are kept out of this reference.

Inverse weighted empirical CDF; midpoint at exact cumulative-weight boundaries. At least four reference units and a definitely positive Q1–Q3 spread are required. This is a display eligibility rule, not statistical validation.

Limitations

FDA Total Diet Study is the only compatible sampling family for sweet corn, cooked as eaten on this basis in the completed corn ledger, so this single-family reference cannot represent other markets. WHO regions are reporting regions, not growing areas. Many results are non-detects with differing limits, which widens the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

FDA Total Diet Study

Reference version and interpretation

Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.

hmi-pooled-reference-v2:corn-sweet_cooked-fw-U:1ba88c07905a

The reference is computed by HMI from admitted evidence, not copied from a study baseline. It describes the evidence currently in this scope; it is not a worldwide or current-lot benchmark. Source, year and region filters do not change it. Different HMI scopes are not one common ranking.

How metals reach corn

Corn takes up cadmium and nickel from soil into the grain, while lead and mercury reach the grain more from air and dust deposited on the plant.^{3Abatemi-Usman S, Akindele O, Ayanlade A, Perez M, Attahiru I, Norton G, Feldmann J, Krupp E · 2023Trace elements concentrations in soil contaminate corn in the vicinity of a cement-manufacturing plant: potential health implicationsJournal of Exposure Science & Environmental EpidemiologyRead source →}^{5Li R, Wu H, Ding J, Fu W, Gan L, Li Y · 2017Mercury pollution in vegetables, grains and soils from areas surrounding coal-fired power plantsScientific ReportsRead source →}^{8Gu Q, Yu T, Yang Z, Ji J, Hou Q, Wang L, Wei X, Zhang Q · 2019Prediction and risk assessment of five heavy metals in maize and peanut: a case study of Guangxi, ChinaEnvironmental Toxicology and PharmacologyRead source →} In Guangxi, maize grain cadmium and lead uptake fell as soil organic carbon and manganese rose, and cadmium uptake also fell with higher soil pH, across 65 paired grain and soil samples.^{8Gu Q, Yu T, Yang Z, Ji J, Hou Q, Wang L, Wei X, Zhang Q · 2019Prediction and risk assessment of five heavy metals in maize and peanut: a case study of Guangxi, ChinaEnvironmental Toxicology and PharmacologyRead source →} In Bangladesh, soil-to-grain transfer factors for maize were 0.054 for cadmium and 0.014 for lead, so grain carried a small fraction of soil levels.^{7Islam MS, Ahmed MK, Habibullah-Al-Mamun M · 2014Heavy Metals in Cereals and Pulses: Health Implications in BangladeshJournal of Agricultural and Food ChemistryRead source →}

Industrial emissions raise the metals in corn grown nearby. At five farms around a cement plant at Obajana, Kogi State, Nigeria, maize harvested in 2017 averaged 230–380 µg/kg lead on a dry-weight basis at the three downwind farms against 20 µg/kg at a control farm 18 km upwind.^{3Abatemi-Usman S, Akindele O, Ayanlade A, Perez M, Attahiru I, Norton G, Feldmann J, Krupp E · 2023Trace elements concentrations in soil contaminate corn in the vicinity of a cement-manufacturing plant: potential health implicationsJournal of Exposure Science & Environmental EpidemiologyRead source →} Near two Chinese coal-fired power plants, maize mercury fell from about 21 µg/kg at 1 km to 4.7–6.7 µg/kg at 3 km and 1.06 µg/kg at 5 km, on a fresh-weight basis, against 0.72 µg/kg in maize from a grocery store more than 55 km away.^{5Li R, Wu H, Ding J, Fu W, Gan L, Li Y · 2017Mercury pollution in vegetables, grains and soils from areas surrounding coal-fired power plantsScientific ReportsRead source →} Maize from a village 2.5 km from a battery plant in Henan averaged 140 µg/kg lead and 70 µg/kg mercury, with the basis not stated.^{16Jiang Y, Ma J, Ruan X · 2020Compound health risk assessment of cumulative heavy metal exposure: A case study of a village near a battery factory in Henan Province, ChinaEnvironmental Science: Processes & ImpactsRead source →}

Irrigation water and mining waste are the other routes in the evidence. In Egypt, maize irrigated with sewage or industrial wastewater carried 260–550 µg/kg lead and 38–112 µg/kg cadmium, against 30–40 µg/kg lead and 9–10 µg/kg cadmium or less with Nile or ground water, basis not stated.^{4Adel S. El-Hassanin, Magdy R. Samak, Gomaa N. Abdel-Rahman, Yahia H. Abu-Sree, Essam M. Saleh · 2020Risk assessment of human exposure to lead and cadmium in maize grains cultivated in soils irrigated either with low-quality water or freshwaterToxicology Reports 7:10-15Read source →} In a high-arsenic coal-burning area of Shaanxi, China, corn dried before analysis held 4,240 µg/kg arsenic, and a corn sample from a gold-mining orchard in Ecuador held 740 µg/kg arsenic and 1,620 µg/kg nickel.^{14Romero-Crespo P, Jiménez-Oyola S, Salgado-Almeida B, Zambrano-Anchundia J, Goyburo-Chávez C, González-Valoys A, Higueras P · 2023Trace elements in farmland soils and crops, and probabilistic health risk assessment in areas influenced by mining activity in EcuadorEnvironmental Geochemistry and HealthRead source →}^{26Bai AM, Li Q, Li Y, Fan ZX, Li XQ, Tan WH, Cao DY, Kang YJ · 2022Investigation Into Environmental Selenium and Arsenic Levels and Arseniasis Prevalence in an Arsenic-Affected Coal-Burning AreaFrontiers in NutritionRead source →}

Does living near a factory or power plant affect corn grown there?

In the studies available, yes: maize downwind of a cement plant averaged 230–380 µg/kg lead against 20 µg/kg at a control farm, and maize within 1 km of coal-fired power plants held about 21 µg/kg mercury against about 1 µg/kg at 5 km.^{3Abatemi-Usman S, Akindele O, Ayanlade A, Perez M, Attahiru I, Norton G, Feldmann J, Krupp E · 2023Trace elements concentrations in soil contaminate corn in the vicinity of a cement-manufacturing plant: potential health implicationsJournal of Exposure Science & Environmental EpidemiologyRead source →}^{5Li R, Wu H, Ding J, Fu W, Gan L, Li Y · 2017Mercury pollution in vegetables, grains and soils from areas surrounding coal-fired power plantsScientific ReportsRead source →} These are single observational studies, so the size of the effect elsewhere depends on emissions, wind and distance.^{3Abatemi-Usman S, Akindele O, Ayanlade A, Perez M, Attahiru I, Norton G, Feldmann J, Krupp E · 2023Trace elements concentrations in soil contaminate corn in the vicinity of a cement-manufacturing plant: potential health implicationsJournal of Exposure Science & Environmental EpidemiologyRead source →}^{5Li R, Wu H, Ding J, Fu W, Gan L, Li Y · 2017Mercury pollution in vegetables, grains and soils from areas surrounding coal-fired power plantsScientific ReportsRead source →}

Which forms and regions measured lower

For lead, fresh and cooked sweet corn measured lowest in the evidence. Frozen corn boiled as eaten had lead below 4 µg/kg in all 27 US Total Diet Study composites from 2017 to 2020, and only 1 of 65 cooked sweet corn results submitted to GEMS/Food from the Americas in 2000–2017 was detected.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}^{2U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →} Raw sweet corn had median lead below 10 µg/kg in European and South-East Asian submissions and below 1.4 µg/kg in 65 results from the Americas in 2014–2016, while maize grain had a median below 20 µg/kg in Europe.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →} Sweet corn is mostly water, so these per-kilogram differences do not show that sweet corn plants take up less lead than grain maize.

Among regions reporting maize grain, European results were lowest for lead and Western Pacific results highest.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →} Western Pacific submissions from 2001 to 2010, almost all labelled domestic, had a median of 29–50 µg/kg and 24 of 327 above 200 µg/kg, against 8 of 890 in Europe.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →} Within Europe, maize labelled imported had a median below 17 µg/kg and a highest detected value of 155 µg/kg, against a median below 20 µg/kg and a highest value of 790 µg/kg for domestic maize, a tentative difference from 48 imported results.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →} WHO regions are reporting regions, not growing areas, so this does not identify producing countries with lower lead.

European maize lead also fell over time.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →} 4 of 233 grain results from 2001–2007 and 4 of 257 from 2008–2013 exceeded 200 µg/kg, against none of 400 from 2014–2020.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}

For cadmium, monitored maize grain and sweet corn were both low, and imported sweet corn measured lower than domestic sweet corn in Europe.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →} European grain had a median below 3.2 µg/kg, and European sweet corn a median of 1–4 µg/kg; sweet corn labelled imported had a median below 2.4 µg/kg against 2.6–4 µg/kg for domestic, from 138 and 129 results.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →} Field surveys in China were higher: maize from Guizhou karst fields averaged 43 µg/kg with 13.5% above 100 µg/kg, and maize from an industrial area near Chengdu averaged 260 µg/kg, both on a dry-weight basis.^{6Liu Q, Li X, He L · 2022Health risk assessment of heavy metals in soils and food crops from a coexist area of heavily industrialized and intensively cropping in the Chengdu Plain, Sichuan, ChinaFrontiers in ChemistryRead source →}^{12Li X, Zhou L, Zhang C, Li D, Wang Z, Sun D, Liao C, Zhang Q · 2022Spatial distribution and risk assessment of fluorine and cadmium in rice, corn, and wheat grains in most karst regions of Guizhou province, ChinaFrontiers in NutritionRead source →} Maize from Nanyang Basin fields in Henan averaged 18 µg/kg cadmium on an air-dried basis, showing that ordinary Chinese fields are not uniformly high.^{18Liu Z, Wang L, Yan M, Tian Y, Ma B, Xie Q · 2025Heavy metal synergistic pollution risk assessment in the soil-crop system of the Nanyang BasinScientific ReportsRead source →}

For arsenic, maize grain is generally low but has a wider upper tail than sweet corn.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →} European total arsenic medians were below 12–15 µg/kg for grain and below 10 µg/kg for sweet corn, but 7 of 721 grain results exceeded 300 µg/kg, the Mercosur cereal limit, against a highest sweet corn value of 27 µg/kg in Europe.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}^{27MERCOSUR Grupo Mercado Comun · 2011MERCOSUR/GMC/RES. No. 12/11: Reglamento Tecnico MERCOSUR sobre Limites Maximos de Contaminantes Inorganicos en AlimentosMERCOSUR/GMC/RES. No. 12/11Read source →} Only 12 maize results were speciated for inorganic arsenic, and 2 were detected, at 8 and 310 µg/kg.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →} Maize from Bangladesh fields averaged 640 µg/kg total arsenic on a dry-weight basis, and Sri Lankan farm maize averaged 91 µg/kg wet weight with most results below detection, so arsenic depends strongly on local soil and water.^{7Islam MS, Ahmed MK, Habibullah-Al-Mamun M · 2014Heavy Metals in Cereals and Pulses: Health Implications in BangladeshJournal of Agricultural and Food ChemistryRead source →}^{19Edirisinghe EMRKB, Jinadasa BKKK · 2019Arsenic and cadmium concentrations in legumes and cereals grown in the North Central Province, Sri Lanka and assessment of their health riskInternational Journal of Food Contamination 6:3Read source →}

Is sweet corn lower in heavy metals than maize grain?

Per kilogram, yes, for lead in the monitoring evidence: raw sweet corn medians were below 1.4–10 µg/kg and cooked US sweet corn was below 4 µg/kg in every composite, against a European grain median below 20 µg/kg.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}^{2U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →} Sweet corn is mostly water and grain is dry, so this reflects the food as eaten rather than lower uptake, and the EU sets a lower lead limit for sweet corn (100 µg/kg) than for cereals (200 µg/kg).^{9European Commission · 2023Commission Regulation (EU) 2023/915 of 25 April 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source →}

Which regions reported the lowest lead in maize grain?

European submissions, with a median below 20 µg/kg and 8 of 890 results above 200 µg/kg, against 24 of 327 above 200 µg/kg in Western Pacific submissions from 2001–2010.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →} These are reporting markets, mostly of domestic grain, so they show where testing found lower lead rather than which countries grow cleaner maize.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}

Drying, cooking and processing

No study in the library measured the same corn before and after washing, husking, milling, soaking or cooking for metals. Cooking was compared only across different samples: cooked sweet corn submitted to GEMS/Food had lead and cadmium medians similar to raw sweet corn from the same region, with overlapping reporting limits.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →} Heat does not destroy metals, so cooking can lower a concentration only by moving metal into water or adding water to the food.

Drying works the other way. Field studies report dried grain, and drying raises the concentration per kilogram because water is removed, so dry-weight results cannot be set against sweet corn as eaten.^{3Abatemi-Usman S, Akindele O, Ayanlade A, Perez M, Attahiru I, Norton G, Feldmann J, Krupp E · 2023Trace elements concentrations in soil contaminate corn in the vicinity of a cement-manufacturing plant: potential health implicationsJournal of Exposure Science & Environmental EpidemiologyRead source →}^{15Saleem M, Wang Y, Pierce D, Sens DA, Somji S, Garrett SH · 2025Concentration and Potential Non-Carcinogenic and Carcinogenic Health Risk Assessment of Metals in Locally Grown VegetablesFoodsRead source →}^{12Li X, Zhou L, Zhang C, Li D, Wang Z, Sun D, Liao C, Zhang Q · 2022Spatial distribution and risk assessment of fluorine and cadmium in rice, corn, and wheat grains in most karst regions of Guizhou province, ChinaFrontiers in NutritionRead source →} Fresh sweet corn from a North Dakota farmers’ market, measured after oven drying, had 7 µg/kg lead and 6 µg/kg cadmium on a dry-weight basis.^{15Saleem M, Wang Y, Pierce D, Sens DA, Somji S, Garrett SH · 2025Concentration and Potential Non-Carcinogenic and Carcinogenic Health Risk Assessment of Metals in Locally Grown VegetablesFoodsRead source →}

Milled and processed maize foods are outside this page, but one comparison shows why corn matters to their contamination. European infant porridges and cakes that mixed rice with maize and other grains had median inorganic arsenic of 10 and 8 µg/kg against 66 and 60 µg/kg for pure rice products, although maize’s own contribution was not separated.^{28Carey M, Donaldson E, Signes-Pastor AJ, Meharg AA · 2018Dilution of rice with other gluten free grains to lower inorganic arsenic in foods for young children in response to European Union regulations provides impetus to setting stricter standardsPLoS ONERead source →}

Mitigation from field to lot

Measured or observed controls for metals in corn act at the field and at lot release. Field siting has the clearest evidence: grain from farms downwind of a cement plant, irrigated with wastewater, or within 3 km of coal-fired power plants carried several to many times more lead or mercury than grain from control sites in the same studies.^{3Abatemi-Usman S, Akindele O, Ayanlade A, Perez M, Attahiru I, Norton G, Feldmann J, Krupp E · 2023Trace elements concentrations in soil contaminate corn in the vicinity of a cement-manufacturing plant: potential health implicationsJournal of Exposure Science & Environmental EpidemiologyRead source →}^{4Adel S. El-Hassanin, Magdy R. Samak, Gomaa N. Abdel-Rahman, Yahia H. Abu-Sree, Essam M. Saleh · 2020Risk assessment of human exposure to lead and cadmium in maize grains cultivated in soils irrigated either with low-quality water or freshwaterToxicology Reports 7:10-15Read source →}^{5Li R, Wu H, Ding J, Fu W, Gan L, Li Y · 2017Mercury pollution in vegetables, grains and soils from areas surrounding coal-fired power plantsScientific ReportsRead source →} These are observational comparisons, not tested interventions, and they come from single studies in Nigeria, Egypt and China.^{3Abatemi-Usman S, Akindele O, Ayanlade A, Perez M, Attahiru I, Norton G, Feldmann J, Krupp E · 2023Trace elements concentrations in soil contaminate corn in the vicinity of a cement-manufacturing plant: potential health implicationsJournal of Exposure Science & Environmental EpidemiologyRead source →}^{4Adel S. El-Hassanin, Magdy R. Samak, Gomaa N. Abdel-Rahman, Yahia H. Abu-Sree, Essam M. Saleh · 2020Risk assessment of human exposure to lead and cadmium in maize grains cultivated in soils irrigated either with low-quality water or freshwaterToxicology Reports 7:10-15Read source →}^{5Li R, Wu H, Ding J, Fu W, Gan L, Li Y · 2017Mercury pollution in vegetables, grains and soils from areas surrounding coal-fired power plantsScientific ReportsRead source →}

Crop choice changes exposure on contaminated land. Near the Chinese power plants, maize held about a third of the mercury of rice at the same locations (21 against 63 µg/kg at 1 km), and in the Chengdu industrial area maize averaged 260 µg/kg cadmium against 460 µg/kg for rice.^{5Li R, Wu H, Ding J, Fu W, Gan L, Li Y · 2017Mercury pollution in vegetables, grains and soils from areas surrounding coal-fired power plantsScientific ReportsRead source →}^{6Liu Q, Li X, He L · 2022Health risk assessment of heavy metals in soils and food crops from a coexist area of heavily industrialized and intensively cropping in the Chengdu Plain, Sichuan, ChinaFrontiers in ChemistryRead source →} In Guangxi, soils richer in organic carbon and manganese, and with higher pH, gave lower cadmium uptake into maize grain, which supports liming and organic amendments as plausible levers, although no amendment was tested on maize grain in the library.^{8Gu Q, Yu T, Yang Z, Ji J, Hou Q, Wang L, Wei X, Zhang Q · 2019Prediction and risk assessment of five heavy metals in maize and peanut: a case study of Guangxi, ChinaEnvironmental Toxicology and PharmacologyRead source →}

At release, the supported control is lot testing against the destination limit with an adequate method.^{9European Commission · 2023Commission Regulation (EU) 2023/915 of 25 April 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source →}^{10Codex Alimentarius Commission · 1995General Standard for Contaminants and Toxins in Food and Feed (CXS 193-1995)Codex Alimentarius (Joint FAO/WHO Food Standards Programme)Read source →} A portable screening method recovered 95–110% of cadmium and lead added to corn, which supports rapid screening, while laboratory confirmation remains necessary.^{29Tian W, Zhou M, Liu Y, Wu Y, Zhang J, Chen X, Wang S · 2023A rapid magnetic-based purification of Cd2+ and Pb2+ prior to portable electrochemical determination for grainFood Chemistry: XRead source →}

About this table

ControlMaterialEffectsEvidence

Control

Material

Effects

Evidence

Grow corn away from cement plants and other industrial emitterscultivation · As reported

Corn

Pb · Increased

1

Abatemi-Usman et al. 2023

HMI source record · Original source

One dataset family. Linked analytes, repeated seasons and reports are not independent studies.

Effects and comparators

LeadIncreasedDownwind farms higher (observational)Grain lead, dry weightFarm 2.3 km downwind against control farmMaize grain, dry weightHigh · HMI calculates the relative change from the retained source means: (380 − 20) / 20 × 100 = 1800.0%. This is a descriptive contrast of means; no confidence interval or significance test is inferred.

LeadIncreasedDownwind farms higher (observational)Grain lead, dry weightFarm 0.7 km downwind against control farmMaize grain, dry weightHigh · HMI calculates the relative change from the retained source means: (230 − 20) / 20 × 100 = 1050.0%. This is a descriptive contrast of means; no confidence interval or significance test is inferred.

Downwind farms against the upwind control farm, same harvest and method; 12–24 cobs per farm.

How magnitude is classified

HMI editorial magnitude bands: Low is a change greater than 0% and below 25%; Moderate is 25% to below 50%; High is 50% or more, relative to that control’s own comparator. Direction is shown separately. These are descriptive display bands, not validated efficacy cutoffs, occurrence-baseline positions, statistical significance, evidence certainty, safety or net benefit. A range spanning bands retains both labels; a qualitative label has no implied percentage.

Control in context

Maize from the three farms downwind of the plant averaged 230–380 µg/kg lead, against 20 µg/kg at a control farm 18 km upwind; a farm 2.7 km upwind averaged 10 µg/kg.

Context	Selected control
Material	Maize grain from five farms around a cement plant, Obajana, Kogi State, Nigeria, 2017 harvest
Stage	cultivation
Audience	Ingredient suppliers · Brands
Period	As reported
Conditions	Farmland near a cement plant; wind direction mattered more than distance.
Tested scale	Field survey
Sample units	Source sampling units; no independent intervention units unless stated.
Trade-offs	Other metals, yield and cost not quantified unless stated.
Verification	Confirm with lot-specific lead and cadmium results on the form sold, using an adequate quantification limit.

Design, applicability and operating conditions

Observational field survey. Farmland near a cement plant; wind direction mattered more than distance.

One study family.

As reported by the source

Reduces metal reaching corn, or detects it before release.

Source measurements and linked outcomes

Analyte	Period	Effect	Converted values	Original means (SD)	Basis	Locator
Lead (Pb)	As reported	Downwind farms higher (observational)	20 → 380 µg/kg	Absolute values unextracted	Maize grain, dry weight	Table 4, p. 5
Lead (Pb)	As reported	Downwind farms higher (observational)	20 → 230 µg/kg	Absolute values unextracted	Maize grain, dry weight	Table 4, p. 5

Observational; one plant and harvest.

Differences are read from the source means or medians shown in outcomes.

Basis as stated in outcomes; no mass balance reported.

Trade-offs and implementation

Mycotoxins are outside this table.

Not assessed.

Not quantified.

Not assessed.

Applicability and verification

Farmland near a cement plant; wind direction mattered more than distance.

Lot testing.

See source.

Extraction limits and next actions

Unresolved field	Next action
controlled field or commercial-scale intervention effect	No controlled field or commercial corn intervention study in the library; keep effects unquantified unless measured.

Provenance and assessment

As disclosed by the source.

Source facts and HMI calculations are distinguished above. These selected source findings do not constitute a systematic review; outcome-level appraisal remains incomplete.

Irrigate corn with fresh or ground water, not wastewatercultivation · As reported

Corn

Pb · Increased

Cd · Increased

1

El-Hassanin et al. 2020

HMI source record · Original source

One dataset family. Linked analytes, repeated seasons and reports are not independent studies.

Effects and comparators

LeadIncreasedWastewater irrigation higher (observational)Grain leadKafr-Dokhmais against Al-Hawia (Kafr El-Sheikh)Maize grain, basis not statedHigh · HMI calculates the relative change from the retained source means: (550 − 30) / 30 × 100 = 1733.3%. This is a descriptive contrast of means; no confidence interval or significance test is inferred.

CadmiumIncreasedWastewater irrigation higher (observational)Grain cadmiumAl-Nasiria against Al-Hawia (Kafr El-Sheikh)Maize grain, basis not statedHigh · HMI calculates the relative change from the retained source means: (112 − 10) / 10 × 100 = 1020.0%. This is a descriptive contrast of means; no confidence interval or significance test is inferred.

Wastewater-irrigated sites against the fresh-water site in the same governorate; three field points per site.

How magnitude is classified

HMI editorial magnitude bands: Low is a change greater than 0% and below 25%; Moderate is 25% to below 50%; High is 50% or more, relative to that control’s own comparator. Direction is shown separately. These are descriptive display bands, not validated efficacy cutoffs, occurrence-baseline positions, statistical significance, evidence certainty, safety or net benefit. A range spanning bands retains both labels; a qualitative label has no implied percentage.

Control in context

Maize irrigated with sewage or industrial wastewater carried 260–550 µg/kg lead and 38–112 µg/kg cadmium; maize irrigated with Nile or ground water in the same governorates carried 30 µg/kg lead and 10 µg/kg cadmium or less.

Context	Selected control
Material	Maize grain from nine sites in Beheira, Kafr El-Sheikh and Giza, Egypt, August 2017
Stage	cultivation
Audience	Ingredient suppliers · Brands
Period	As reported
Conditions	Where low-quality irrigation water is used.
Tested scale	Field survey
Sample units	Source sampling units; no independent intervention units unless stated.
Trade-offs	Other metals, yield and cost not quantified unless stated.
Verification	Confirm with lot-specific lead and cadmium results on the form sold, using an adequate quantification limit.

Design, applicability and operating conditions

Observational field survey. Where low-quality irrigation water is used.

One study family.

As reported by the source

Reduces metal reaching corn, or detects it before release.

Source measurements and linked outcomes

Analyte	Period	Effect	Converted values	Original means (SD)	Basis	Locator
Lead (Pb)	As reported	Wastewater irrigation higher (observational)	30 → 550 µg/kg	Absolute values unextracted	Maize grain, basis not stated	Table 4
Cadmium (Cd)	As reported	Wastewater irrigation higher (observational)	10 → 112 µg/kg	Absolute values unextracted	Maize grain, basis not stated	Table 5

Observational; basis not stated; one season.

Differences are read from the source means or medians shown in outcomes.

Basis as stated in outcomes; no mass balance reported.

Trade-offs and implementation

Mycotoxins are outside this table.

Not assessed.

Not quantified.

Not assessed.

Applicability and verification

Where low-quality irrigation water is used.

Lot testing.

See source.

Extraction limits and next actions

Unresolved field	Next action
controlled field or commercial-scale intervention effect	No controlled field or commercial corn intervention study in the library; keep effects unquantified unless measured.

Provenance and assessment

As disclosed by the source.

Source facts and HMI calculations are distinguished above. These selected source findings do not constitute a systematic review; outcome-level appraisal remains incomplete.

Keep corn fields away from coal-fired power plantscultivation · As reported

Corn

tHg · Increased

tHg · Decreased

1

Li et al. 2017

HMI source record · Original source

One dataset family. Linked analytes, repeated seasons and reports are not independent studies.

Effects and comparators

Total mercuryIncreasedNear-plant maize higher (observational)Grain mercury, fresh weight1 km from plant B against grocery controlMaize grain, fresh weightHigh · HMI calculates the relative change from the retained source means: (21.18 − 0.72) / 0.72 × 100 = 2841.7%. This is a descriptive contrast of means; no confidence interval or significance test is inferred.

Total mercuryDecreasedLower with distance (observational)Grain mercury, fresh weight5 km against 1 km from plant BMaize grain, fresh weightHigh · HMI calculates the relative change from the retained source means: (1.06 − 21.18) / 21.18 × 100 = -95.0%. This is a descriptive contrast of means; no confidence interval or significance test is inferred.

Distance gradient from each plant against a retail control.

How magnitude is classified

HMI editorial magnitude bands: Low is a change greater than 0% and below 25%; Moderate is 25% to below 50%; High is 50% or more, relative to that control’s own comparator. Direction is shown separately. These are descriptive display bands, not validated efficacy cutoffs, occurrence-baseline positions, statistical significance, evidence certainty, safety or net benefit. A range spanning bands retains both labels; a qualitative label has no implied percentage.

Control in context

Maize mercury fell from about 21 µg/kg at 1 km to 4.7–6.7 µg/kg at 3 km and 1.06 µg/kg at 5 km; maize bought at a grocery store more than 55 km away held 0.72 µg/kg.

Context	Selected control
Material	Maize grain near two coal-fired power plants, China, 2015
Stage	cultivation
Audience	Ingredient suppliers · Brands
Period	As reported
Conditions	Areas downwind of coal combustion.
Tested scale	Field survey
Sample units	Source sampling units; no independent intervention units unless stated.
Trade-offs	Other metals, yield and cost not quantified unless stated.
Verification	Confirm with lot-specific lead and cadmium results on the form sold, using an adequate quantification limit.

Design, applicability and operating conditions

Observational field survey. Areas downwind of coal combustion.

One study family.

As reported by the source

Reduces metal reaching corn, or detects it before release.

Source measurements and linked outcomes

Analyte	Period	Effect	Converted values	Original means (SD)	Basis	Locator
Total mercury (tHg)	As reported	Near-plant maize higher (observational)	0.72 → 21.18 µg/kg	Absolute values unextracted	Maize grain, fresh weight	Table 2
Total mercury (tHg)	As reported	Lower with distance (observational)	21.18 → 1.06 µg/kg	Absolute values unextracted	Maize grain, fresh weight	Table 2

Observational; sample counts per site not stated.

Differences are read from the source means or medians shown in outcomes.

Basis as stated in outcomes; no mass balance reported.

Trade-offs and implementation

Mycotoxins are outside this table.

Not assessed.

Not quantified.

Not assessed.

Applicability and verification

Areas downwind of coal combustion.

Lot testing.

See source.

Extraction limits and next actions

Unresolved field	Next action
controlled field or commercial-scale intervention effect	No controlled field or commercial corn intervention study in the library; keep effects unquantified unless measured.

Provenance and assessment

As disclosed by the source.

Source facts and HMI calculations are distinguished above. These selected source findings do not constitute a systematic review; outcome-level appraisal remains incomplete.

Prefer maize to rice on mercury-affected landcultivation · As reported

Corn

tHg · Decreased

1

Li et al. 2017

HMI source record · Original source

One dataset family. Linked analytes, repeated seasons and reports are not independent studies.

Effects and comparators

Total mercuryDecreasedMaize lower than rice (observational)Grain mercury, fresh weightMaize against rice at site A1Grain, fresh weightHigh · HMI calculates the relative change from the retained source means: (21.02 − 62.95) / 62.95 × 100 = -66.6%. This is a descriptive contrast of means; no confidence interval or significance test is inferred.

Rice against maize grain from the same locations.

How magnitude is classified

HMI editorial magnitude bands: Low is a change greater than 0% and below 25%; Moderate is 25% to below 50%; High is 50% or more, relative to that control’s own comparator. Direction is shown separately. These are descriptive display bands, not validated efficacy cutoffs, occurrence-baseline positions, statistical significance, evidence certainty, safety or net benefit. A range spanning bands retains both labels; a qualitative label has no implied percentage.

Control in context

Rice held more mercury than maize at every location, for example 62.95 against 21.02 µg/kg at 1 km from plant A.

Context	Selected control
Material	Maize and rice grain from the same locations near coal-fired power plants, China, 2015
Stage	cultivation
Audience	Ingredient suppliers · Brands
Period	As reported
Conditions	Crop choice on mercury-affected land; does not remove the source.
Tested scale	Field survey
Sample units	Source sampling units; no independent intervention units unless stated.
Trade-offs	Other metals, yield and cost not quantified unless stated.
Verification	Confirm with lot-specific lead and cadmium results on the form sold, using an adequate quantification limit.

Design, applicability and operating conditions

Observational field survey. Crop choice on mercury-affected land; does not remove the source.

One study family.

As reported by the source

Reduces metal reaching corn, or detects it before release.

Source measurements and linked outcomes

Analyte	Period	Effect	Converted values	Original means (SD)	Basis	Locator
Total mercury (tHg)	As reported	Maize lower than rice (observational)	62.95 → 21.02 µg/kg	Absolute values unextracted	Grain, fresh weight	Table 2

Observational; one study.

Differences are read from the source means or medians shown in outcomes.

Basis as stated in outcomes; no mass balance reported.

Trade-offs and implementation

Mycotoxins are outside this table.

Not assessed.

Not quantified.

Not assessed.

Applicability and verification

Crop choice on mercury-affected land; does not remove the source.

Lot testing.

See source.

Extraction limits and next actions

Unresolved field	Next action
controlled field or commercial-scale intervention effect	No controlled field or commercial corn intervention study in the library; keep effects unquantified unless measured.

Provenance and assessment

As disclosed by the source.

Source facts and HMI calculations are distinguished above. These selected source findings do not constitute a systematic review; outcome-level appraisal remains incomplete.

Prefer maize to rice on cadmium-affected landcultivation · As reported

Corn

Cd · Decreased

Pb · Decreased

1

Liu et al. 2022

HMI source record · Original source

One dataset family. Linked analytes, repeated seasons and reports are not independent studies.

Effects and comparators

CadmiumDecreasedMaize lower than rice (observational)Grain cadmium, dry weightMaize against riceGrain, dry weightModerate · HMI calculates the relative change from the retained source means: (260 − 460) / 460 × 100 = -43.5%. This is a descriptive contrast of means; no confidence interval or significance test is inferred.

LeadDecreasedAbout the same as rice; above the cereal limitGrain lead, dry weightMaize against riceGrain, dry weightLow · HMI calculates the relative change from the retained source means: (290 − 300) / 300 × 100 = -3.3%. This is a descriptive contrast of means; no confidence interval or significance test is inferred.

Maize (10 composites) against rice (40 composites) from the same study area.

How magnitude is classified

HMI editorial magnitude bands: Low is a change greater than 0% and below 25%; Moderate is 25% to below 50%; High is 50% or more, relative to that control’s own comparator. Direction is shown separately. These are descriptive display bands, not validated efficacy cutoffs, occurrence-baseline positions, statistical significance, evidence certainty, safety or net benefit. A range spanning bands retains both labels; a qualitative label has no implied percentage.

Control in context

Maize averaged 260 µg/kg cadmium against 460 µg/kg for rice from the same area, while lead was similar (290 against 300 µg/kg).

Context	Selected control
Material	Maize and rice grain from an industrial and agricultural area near Chengdu, China
Stage	cultivation
Audience	Ingredient suppliers · Brands
Period	As reported
Conditions	Crop choice on cadmium-affected land.
Tested scale	Field survey
Sample units	Source sampling units; no independent intervention units unless stated.
Trade-offs	Other metals, yield and cost not quantified unless stated.
Verification	Confirm with lot-specific lead and cadmium results on the form sold, using an adequate quantification limit.

Design, applicability and operating conditions

Observational field survey. Crop choice on cadmium-affected land.

One study family.

As reported by the source

Reduces metal reaching corn, or detects it before release.

Source measurements and linked outcomes

Analyte	Period	Effect	Converted values	Original means (SD)	Basis	Locator
Cadmium (Cd)	As reported	Maize lower than rice (observational)	460 → 260 µg/kg	Absolute values unextracted	Grain, dry weight	Table 2
Lead (Pb)	As reported	About the same as rice; above the cereal limit	300 → 290 µg/kg	Absolute values unextracted	Grain, dry weight	Table 2

Observational; one study; maize lead stayed above 200 µg/kg.

Differences are read from the source means or medians shown in outcomes.

Basis as stated in outcomes; no mass balance reported.

Trade-offs and implementation

Mycotoxins are outside this table.

Not assessed.

Not quantified.

Not assessed.

Applicability and verification

Crop choice on cadmium-affected land.

Lot testing.

See source.

Extraction limits and next actions

Unresolved field	Next action
controlled field or commercial-scale intervention effect	No controlled field or commercial corn intervention study in the library; keep effects unquantified unless measured.

Provenance and assessment

As disclosed by the source.

Source facts and HMI calculations are distinguished above. These selected source findings do not constitute a systematic review; outcome-level appraisal remains incomplete.

Raise soil pH and organic matter where cadmium is a concernsoil remediation · As reported

Corn

Cd · Context

1

Gu et al. 2019

HMI source record · Original source

One dataset family. Linked analytes, repeated seasons and reports are not independent studies.

Effects and comparators

CadmiumAssociation only; effect of amendment not measuredGrain cadmium bioaccumulationSoil pH, organic carbon and manganeseMaize grain, dry weightContext · No supported numerical treatment contrast is retained for this finding. A direction, market association, source-selection strategy or guidance statement alone does not establish a percentage change.

Regression across 65 paired grain and soil samples; no treatment comparison.

How magnitude is classified

HMI editorial magnitude bands: Low is a change greater than 0% and below 25%; Moderate is 25% to below 50%; High is 50% or more, relative to that control’s own comparator. Direction is shown separately. These are descriptive display bands, not validated efficacy cutoffs, occurrence-baseline positions, statistical significance, evidence certainty, safety or net benefit. A range spanning bands retains both labels; a qualitative label has no implied percentage.

Control in context

Across 65 paired samples, maize grain cadmium and lead uptake fell as soil organic carbon and manganese rose, and cadmium uptake fell with higher pH; no amendment was applied.

Context	Selected control
Material	Maize grain and rhizosphere soil, Guangxi, China, 2015
Stage	soil remediation
Audience	Ingredient suppliers · Brands
Period	As reported
Conditions	Acidic, low-organic soils with cadmium.
Tested scale	Field survey
Sample units	Source sampling units; no independent intervention units unless stated.
Trade-offs	Other metals, yield and cost not quantified unless stated.
Verification	Confirm with lot-specific lead and cadmium results on the form sold, using an adequate quantification limit.

Design, applicability and operating conditions

Observational field survey. Acidic, low-organic soils with cadmium.

One study family.

As reported by the source

Reduces metal reaching corn, or detects it before release.

Source measurements and linked outcomes

Analyte	Period	Effect	Converted values	Original means (SD)	Basis	Locator
Cadmium (Cd)	As reported	Association only; effect of amendment not measured	Numerical baseline not extracted	Absolute values unextracted	Maize grain, dry weight	Regression equations, Results

Associational; no tested liming or amendment on maize grain in the library.

Differences are read from the source means or medians shown in outcomes.

Basis as stated in outcomes; no mass balance reported.

Trade-offs and implementation

Mycotoxins are outside this table.

Not assessed.

Not quantified.

Not assessed.

Applicability and verification

Acidic, low-organic soils with cadmium.

Lot testing.

See source.

Extraction limits and next actions

Unresolved field	Next action
controlled field or commercial-scale intervention effect	No controlled field or commercial corn intervention study in the library; keep effects unquantified unless measured.

Provenance and assessment

As disclosed by the source.

Source facts and HMI calculations are distinguished above. These selected source findings do not constitute a systematic review; outcome-level appraisal remains incomplete.

Ask for origin and lot lead results on maize grainsourcing and procurement · As reported

Corn

Pb · Increased

1

WHO GEMS/Food

HMI source record · Original source

One dataset family. Linked analytes, repeated seasons and reports are not independent studies.

Effects and comparators

LeadIncreasedWestern Pacific medians higher (observational)Median grain lead (upper bounds)WPRO against EURO random samplingMaize grain, as soldHigh · HMI calculates the relative change from the retained source means: (50 − 20) / 20 × 100 = 150.0%. This is a descriptive contrast of means; no confidence interval or significance test is inferred.

Reporting regions and periods within one monitoring dataset.

How magnitude is classified

HMI editorial magnitude bands: Low is a change greater than 0% and below 25%; Moderate is 25% to below 50%; High is 50% or more, relative to that control’s own comparator. Direction is shown separately. These are descriptive display bands, not validated efficacy cutoffs, occurrence-baseline positions, statistical significance, evidence certainty, safety or net benefit. A range spanning bands retains both labels; a qualitative label has no implied percentage.

Control in context

Western Pacific submissions from 2001–2010 had 24 of 327 lead results above 200 µg/kg against 8 of 890 in Europe, and European exceedances fell to none of 400 in 2014–2020.

Context	Selected control
Material	Maize grain submitted to GEMS/Food from Europe and the Western Pacific
Stage	sourcing and procurement
Audience	Ingredient suppliers · Brands
Period	As reported
Conditions	Buyers sourcing maize grain internationally.
Tested scale	Monitoring dataset
Sample units	Source sampling units; no independent intervention units unless stated.
Trade-offs	Other metals, yield and cost not quantified unless stated.
Verification	Confirm with lot-specific lead and cadmium results on the form sold, using an adequate quantification limit.

Design, applicability and operating conditions

Observational field survey. Buyers sourcing maize grain internationally.

One study family.

As reported by the source

Reduces metal reaching corn, or detects it before release.

Source measurements and linked outcomes

Analyte	Period	Effect	Converted values	Original means (SD)	Basis	Locator
Lead (Pb)	As reported	Western Pacific medians higher (observational)	20 → 50 µg/kg	Absolute values unextracted	Maize grain, as sold	primary/gemsfood-corn-records.csv

Observational; reporting regions are not growing areas.

Differences are read from the source means or medians shown in outcomes.

Basis as stated in outcomes; no mass balance reported.

Trade-offs and implementation

Mycotoxins are outside this table.

Not assessed.

Not quantified.

Not assessed.

Applicability and verification

Buyers sourcing maize grain internationally.

Lot testing.

See source.

Extraction limits and next actions

Unresolved field	Next action
controlled field or commercial-scale intervention effect	No controlled field or commercial corn intervention study in the library; keep effects unquantified unless measured.

Provenance and assessment

As disclosed by the source.

Source facts and HMI calculations are distinguished above. These selected source findings do not constitute a systematic review; outcome-level appraisal remains incomplete.

Test each lot against the limit for its formlot acceptance and release · As reported

Corn

Pb · Context

Cd · Context

Guidance

Commission Regulation (EU) 2023/915

HMI source record · Original source

Official guidance; not an independent experimental dataset. Reused across actions without adding studies.

Effects and comparators

LeadRegulatory limit; detection, not removalLead limitCereals 200 µg/kg; sweet corn 100 µg/kgWet weightContext · No supported numerical treatment contrast is retained for this finding. A direction, market association, source-selection strategy or guidance statement alone does not establish a percentage change.

CadmiumRegulatory limit; detection, not removalCadmium limitCereals 100 µg/kg; sweet corn 20 µg/kgWet weightContext · No supported numerical treatment contrast is retained for this finding. A direction, market association, source-selection strategy or guidance statement alone does not establish a percentage change.

Regulatory limits; no measured effect.

How magnitude is classified

HMI editorial magnitude bands: Low is a change greater than 0% and below 25%; Moderate is 25% to below 50%; High is 50% or more, relative to that control’s own comparator. Direction is shown separately. These are descriptive display bands, not validated efficacy cutoffs, occurrence-baseline positions, statistical significance, evidence certainty, safety or net benefit. A range spanning bands retains both labels; a qualitative label has no implied percentage.

Control in context

The EU limits lead at 200 µg/kg and cadmium at 100 µg/kg for cereals, and lead at 100 µg/kg and cadmium at 20 µg/kg for sweet corn, on a wet-weight basis; nickel limits apply from July 2025 for sweet corn (400 µg/kg) and July 2026 for cereals (800 µg/kg).

Context	Selected control
Material	Maize grain and sweet corn placed on the EU market
Stage	lot acceptance and release
Audience	Ingredient suppliers · Brands · Consumers
Period	As reported
Conditions	Corn placed on the EU market.
Tested scale	Regulation
Sample units	Source sampling units; no independent intervention units unless stated.
Trade-offs	Other metals, yield and cost not quantified unless stated.
Verification	Confirm with lot-specific lead and cadmium results on the form sold, using an adequate quantification limit.

Design, applicability and operating conditions

Regulatory or author guidance. Corn placed on the EU market.

One study family.

As reported by the source

Reduces metal reaching corn, or detects it before release.

Source measurements and linked outcomes

Analyte	Period	Effect	Converted values	Original means (SD)	Basis	Locator
Lead (Pb)	As reported	Regulatory limit; detection, not removal	Numerical baseline not extracted	Absolute values unextracted	Wet weight	Annex I 3.1.11, 3.1.4.2
Cadmium (Cd)	As reported	Regulatory limit; detection, not removal	Numerical baseline not extracted	Absolute values unextracted	Wet weight	Annex I 3.2.12.1, 3.2.4.1

Testing detects contamination; it does not remove it.

Differences are read from the source means or medians shown in outcomes.

Basis as stated in outcomes; no mass balance reported.

Trade-offs and implementation

Mycotoxins are outside this table.

Not assessed.

Not quantified.

Not assessed.

Applicability and verification

Corn placed on the EU market.

Lot testing.

See source.

Extraction limits and next actions

Unresolved field	Next action
controlled field or commercial-scale intervention effect	No controlled field or commercial corn intervention study in the library; keep effects unquantified unless measured.

Provenance and assessment

As disclosed by the source.

Source facts and HMI calculations are distinguished above. These selected source findings do not constitute a systematic review; outcome-level appraisal remains incomplete.

Screen lots rapidly, then confirm in the laboratorylot acceptance and release · As reported

Corn

Cd · Context

Pb · Context

1

Tian et al. 2023

HMI source record · Original source

One dataset family. Linked analytes, repeated seasons and reports are not independent studies.

Effects and comparators

CadmiumMethod recovery 95–110% (screening performance)Recovery of added cadmiumSpiked cornCorn as analysedContext · No supported numerical treatment contrast is retained for this finding. A direction, market association, source-selection strategy or guidance statement alone does not establish a percentage change.

LeadMethod recovery 95–110% (screening performance)Recovery of added leadSpiked cornCorn as analysedContext · No supported numerical treatment contrast is retained for this finding. A direction, market association, source-selection strategy or guidance statement alone does not establish a percentage change.

Recovery of added cadmium and lead in corn samples.

How magnitude is classified

HMI editorial magnitude bands: Low is a change greater than 0% and below 25%; Moderate is 25% to below 50%; High is 50% or more, relative to that control’s own comparator. Direction is shown separately. These are descriptive display bands, not validated efficacy cutoffs, occurrence-baseline positions, statistical significance, evidence certainty, safety or net benefit. A range spanning bands retains both labels; a qualitative label has no implied percentage.

Control in context

A magnetic clean-up with a portable electrochemical sensor recovered 95–110% of cadmium and lead added to corn, supporting on-site screening before laboratory confirmation.

Context	Selected control
Material	Corn spiked with cadmium and lead, laboratory method study
Stage	lot acceptance and release
Audience	Ingredient suppliers · Brands
Period	As reported
Conditions	Grain buyers needing rapid screening.
Tested scale	Laboratory method
Sample units	Source sampling units; no independent intervention units unless stated.
Trade-offs	Other metals, yield and cost not quantified unless stated.
Verification	Confirm with lot-specific lead and cadmium results on the form sold, using an adequate quantification limit.

Design, applicability and operating conditions

Measured method or processing comparison. Grain buyers needing rapid screening.

One study family.

As reported by the source

Reduces metal reaching corn, or detects it before release.

Source measurements and linked outcomes

Analyte	Period	Effect	Converted values	Original means (SD)	Basis	Locator
Cadmium (Cd)	As reported	Method recovery 95–110% (screening performance)	Numerical baseline not extracted	Absolute values unextracted	Corn as analysed	Table 2
Lead (Pb)	As reported	Method recovery 95–110% (screening performance)	Numerical baseline not extracted	Absolute values unextracted	Corn as analysed	Table 2

Method validation only; detection limits as published.

Differences are read from the source means or medians shown in outcomes.

Basis as stated in outcomes; no mass balance reported.

Trade-offs and implementation

Mycotoxins are outside this table.

Not assessed.

Not quantified.

Not assessed.

Applicability and verification

Grain buyers needing rapid screening.

Lot testing.

See source.

Extraction limits and next actions

Unresolved field	Next action
controlled field or commercial-scale intervention effect	No controlled field or commercial corn intervention study in the library; keep effects unquantified unless measured.

Provenance and assessment

As disclosed by the source.

Source facts and HMI calculations are distinguished above. These selected source findings do not constitute a systematic review; outcome-level appraisal remains incomplete.

Blend maize and other grains with rice in infant foodsproduct formulation · As reported

Corn

iAs · Decreased

1

Carey et al. 2018

HMI source record · Original source

One dataset family. Linked analytes, repeated seasons and reports are not independent studies.

Effects and comparators

Inorganic arsenicDecreasedMulti-grain porridge lower (observational)Median inorganic arsenicMulti-grain against pure-rice porridgeAs soldHigh · HMI calculates the relative change from the retained source means: (10 − 66) / 66 × 100 = -84.8%. This is a descriptive contrast of means; no confidence interval or significance test is inferred.

Inorganic arsenicDecreasedMulti-grain cakes lower (observational)Median inorganic arsenicMulti-grain against pure-rice cakesAs soldHigh · HMI calculates the relative change from the retained source means: (8 − 60) / 60 × 100 = -86.7%. This is a descriptive contrast of means; no confidence interval or significance test is inferred.

Multi-grain against pure-rice products, as sold.

How magnitude is classified

HMI editorial magnitude bands: Low is a change greater than 0% and below 25%; Moderate is 25% to below 50%; High is 50% or more, relative to that control’s own comparator. Direction is shown separately. These are descriptive display bands, not validated efficacy cutoffs, occurrence-baseline positions, statistical significance, evidence certainty, safety or net benefit. A range spanning bands retains both labels; a qualitative label has no implied percentage.

Control in context

Infant porridges and cakes mixing rice with maize and other gluten-free grains had median inorganic arsenic of 10 and 8 µg/kg, against 66 and 60 µg/kg for pure rice products; maize’s own share was not measured.

Context	Selected control
Material	Infant porridges and cakes sold in Europe
Stage	product formulation
Audience	Ingredient suppliers · Brands
Period	As reported
Conditions	Infant food formulation; maize contribution not isolated.
Tested scale	Market survey
Sample units	Source sampling units; no independent intervention units unless stated.
Trade-offs	Other metals, yield and cost not quantified unless stated.
Verification	Confirm with lot-specific lead and cadmium results on the form sold, using an adequate quantification limit.

Design, applicability and operating conditions

Observational field survey. Infant food formulation; maize contribution not isolated.

One study family.

As reported by the source

Reduces metal reaching corn, or detects it before release.

Source measurements and linked outcomes

Analyte	Period	Effect	Converted values	Original means (SD)	Basis	Locator
Inorganic arsenic (iAs)	As reported	Multi-grain porridge lower (observational)	66 → 10 µg/kg	Absolute values unextracted	As sold	Results
Inorganic arsenic (iAs)	As reported	Multi-grain cakes lower (observational)	60 → 8 µg/kg	Absolute values unextracted	As sold	Results

Observational market comparison.

Differences are read from the source means or medians shown in outcomes.

Basis as stated in outcomes; no mass balance reported.

Trade-offs and implementation

Mycotoxins are outside this table.

Not assessed.

Not quantified.

Not assessed.

Applicability and verification

Infant food formulation; maize contribution not isolated.

Lot testing.

See source.

Extraction limits and next actions

Unresolved field	Next action
controlled field or commercial-scale intervention effect	No controlled field or commercial corn intervention study in the library; keep effects unquantified unless measured.

Provenance and assessment

As disclosed by the source.

Source facts and HMI calculations are distinguished above. These selected source findings do not constitute a systematic review; outcome-level appraisal remains incomplete.

Trade-offs and limits of controls

Choosing corn instead of rice on contaminated land lowers mercury and cadmium in the grain but does not remove the source.^{5Li R, Wu H, Ding J, Fu W, Gan L, Li Y · 2017Mercury pollution in vegetables, grains and soils from areas surrounding coal-fired power plantsScientific ReportsRead source →}^{6Liu Q, Li X, He L · 2022Health risk assessment of heavy metals in soils and food crops from a coexist area of heavily industrialized and intensively cropping in the Chengdu Plain, Sichuan, ChinaFrontiers in ChemistryRead source →} The same Chengdu maize still averaged 290 µg/kg lead, above the 200 µg/kg cereal limit, so a crop switch can trade one problem for another.^{6Liu Q, Li X, He L · 2022Health risk assessment of heavy metals in soils and food crops from a coexist area of heavily industrialized and intensively cropping in the Chengdu Plain, Sichuan, ChinaFrontiers in ChemistryRead source →}^{9European Commission · 2023Commission Regulation (EU) 2023/915 of 25 April 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source →}

Metals do not move together. In Burkina Faso markets, maize from Ouagadougou and Cinkassé had the same median lead (230 µg/kg) but nickel of 670 against 1,090 µg/kg, and maize from Bangladesh fields carried 1,900 µg/kg chromium and 1,400 µg/kg nickel alongside 310 µg/kg lead on a dry-weight basis.^{7Islam MS, Ahmed MK, Habibullah-Al-Mamun M · 2014Heavy Metals in Cereals and Pulses: Health Implications in BangladeshJournal of Agricultural and Food ChemistryRead source →}^{11Bazie SR, Compaore MKA, Bande M, Kpoda SD, Meda NSBR, Ouedraogo Kangambega TM, Ilboudo I, Sandwidi BY, Nikiema F, Yakoro A, Bassole IHN, Hien H, Kabre E · 2022Evaluation of metallic trace elements contents in some major raw foodstuffs in Burkina Faso and health risk assessmentScientific ReportsRead source →} A lot that passes a lead limit therefore says little about cadmium, arsenic or nickel unless those are tested as well.^{9European Commission · 2023Commission Regulation (EU) 2023/915 of 25 April 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source →}

Grain and sweet corn are judged against different limits. A sweet corn lot at 50 µg/kg lead is within the EU sweet corn limit of 100 µg/kg, while the same value in grain would be a quarter of the cereal limit; comparing them per kilogram without moisture mixes two different foods.^{9European Commission · 2023Commission Regulation (EU) 2023/915 of 25 April 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source →}

Testing corn for metals

A useful corn test reports total lead, cadmium and arsenic with quantification limits well below the limits that apply.^{9European Commission · 2023Commission Regulation (EU) 2023/915 of 25 April 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source →}^{10Codex Alimentarius Commission · 1995General Standard for Contaminants and Toxins in Food and Feed (CXS 193-1995)Codex Alimentarius (Joint FAO/WHO Food Standards Programme)Read source →} Many GEMS/Food maize non-detects carried limits of 20–40 µg/kg for lead and 10–25 µg/kg for arsenic, adequate for grain but coarse for sweet corn, where the EU cadmium limit is 20 µg/kg.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}^{9European Commission · 2023Commission Regulation (EU) 2023/915 of 25 April 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source →} The FDA reported cooked corn with limits of 4 µg/kg for lead, 3 µg/kg for arsenic and 1 µg/kg for mercury.^{2U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →}

Several field studies lacked basic quality checks. A Nigerian seasonal survey measured mercury after dry ashing at 550 °C, which drives mercury off, and an Ethiopian market composite was read below the lowest calibration standard; these values are shown but held.^{13Abdullahi N, Dandago MA, Gambo MS, Abubakar SS, Tsoho AU, Idah PG · 2024Seasonal Variation and Uptake Pattern of Heavy Metals in MaizeDutse Journal of Pure and Applied Sciences (DUJOPAS)Read source →}^{22Getu A, Seid Y, Asrade B · 2022Determination of the Level of Heavy Metals in the Selected Cereals from Debre Markos Local Market, Amhara Region, EthiopiaInternational Journal of Analytical ChemistryRead source →} Arsenic in maize should be read as total arsenic unless the laboratory speciated it, because only 12 inorganic arsenic results exist for maize in the evidence.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}

State the form and basis on every result. A dried-grain result, an as-sold grain result and a sweet corn result as eaten are not interchangeable, and the EU and Codex limits for sweet corn apply to kernels and cob without husk on a wet-weight basis.^{9European Commission · 2023Commission Regulation (EU) 2023/915 of 25 April 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source →}^{10Codex Alimentarius Commission · 1995General Standard for Contaminants and Toxins in Food and Feed (CXS 193-1995)Codex Alimentarius (Joint FAO/WHO Food Standards Programme)Read source →}

Buying and verifying corn

Ask for lot-specific lead and cadmium results on the form being bought, with the quantification limit, compared with the destination-market limit.^{9European Commission · 2023Commission Regulation (EU) 2023/915 of 25 April 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source →}^{10Codex Alimentarius Commission · 1995General Standard for Contaminants and Toxins in Food and Feed (CXS 193-1995)Codex Alimentarius (Joint FAO/WHO Food Standards Programme)Read source →} For maize grain the EU, Codex, China, Hong Kong, Korea and India set 200 µg/kg lead and 100 µg/kg cadmium; China and Hong Kong add 20 µg/kg total mercury for maize and 500 µg/kg total arsenic for cereals other than rice, and Mercosur sets 300 µg/kg arsenic.^{9European Commission · 2023Commission Regulation (EU) 2023/915 of 25 April 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source →}^{10Codex Alimentarius Commission · 1995General Standard for Contaminants and Toxins in Food and Feed (CXS 193-1995)Codex Alimentarius (Joint FAO/WHO Food Standards Programme)Read source →}^{30National Health Commission of the People’s Republic of China, State Administration for Market Regulation · 2022GB 2762-2022 National Food Safety Standard: Maximum Levels of Contaminants in FoodsNational Food Safety Standard GB 2762-2022Read source →}^{31Hong Kong e-Legislation · 2025Hong Kong Cap. 132V Food Adulteration (Metallic Contamination) Regulations, consolidated 5 September 2025Hong Kong e-Legislation Cap. 132VRead source →}^{32Korea Food and Drug Administration · 2012Article 2. Common Standards and Specifications for General FoodsKorean Food CodeRead source →}^{33Food Safety and Standards Authority of India · 2016Food Safety and Standards (Contaminants, toxins and Residues) Third Amendment Regulations, 2016Gazette of India, Extraordinary, Part III, Section 4Read source →}^{27MERCOSUR Grupo Mercado Comun · 2011MERCOSUR/GMC/RES. No. 12/11: Reglamento Tecnico MERCOSUR sobre Limites Maximos de Contaminantes Inorganicos en AlimentosMERCOSUR/GMC/RES. No. 12/11Read source →} For sweet corn the EU sets 100 µg/kg lead and 20 µg/kg cadmium and Codex 50 µg/kg for both, and the EU adds nickel limits of 400 µg/kg for fruiting vegetables including sweet corn, applied since July 2025, and 800 µg/kg for cereals from July 2026.^{9European Commission · 2023Commission Regulation (EU) 2023/915 of 25 April 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source →}^{10Codex Alimentarius Commission · 1995General Standard for Contaminants and Toxins in Food and Feed (CXS 193-1995)Codex Alimentarius (Joint FAO/WHO Food Standards Programme)Read source →}

Record where the corn was grown, not only where it was packed.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →} The evidence supports avoiding grain from fields downwind of cement or battery plants, near coal-fired power plants, irrigated with wastewater or on mining land unless lot testing shows otherwise.^{3Abatemi-Usman S, Akindele O, Ayanlade A, Perez M, Attahiru I, Norton G, Feldmann J, Krupp E · 2023Trace elements concentrations in soil contaminate corn in the vicinity of a cement-manufacturing plant: potential health implicationsJournal of Exposure Science & Environmental EpidemiologyRead source →}^{4Adel S. El-Hassanin, Magdy R. Samak, Gomaa N. Abdel-Rahman, Yahia H. Abu-Sree, Essam M. Saleh · 2020Risk assessment of human exposure to lead and cadmium in maize grains cultivated in soils irrigated either with low-quality water or freshwaterToxicology Reports 7:10-15Read source →}^{5Li R, Wu H, Ding J, Fu W, Gan L, Li Y · 2017Mercury pollution in vegetables, grains and soils from areas surrounding coal-fired power plantsScientific ReportsRead source →}^{14Romero-Crespo P, Jiménez-Oyola S, Salgado-Almeida B, Zambrano-Anchundia J, Goyburo-Chávez C, González-Valoys A, Higueras P · 2023Trace elements in farmland soils and crops, and probabilistic health risk assessment in areas influenced by mining activity in EcuadorEnvironmental Geochemistry and HealthRead source →}^{16Jiang Y, Ma J, Ruan X · 2020Compound health risk assessment of cumulative heavy metal exposure: A case study of a village near a battery factory in Henan Province, ChinaEnvironmental Science: Processes & ImpactsRead source →}^{17Bedoya-Perales NS, Escobedo-Pacheco E, Maus D, Neimaier A, Pumi G · 2023Dataset of metals and metalloids in food crops and soils sampled across the mining region of Moquegua in PeruScientific DataRead source →}

Within the monitoring evidence, the lowest-lead options were sweet corn and European-reported maize grain, and recent European grain had no lead results above the cereal limit in 2014–2020.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}^{2U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →} These are descriptive patterns from reporting markets; they support asking for origin and test data, not a preference for any producing country.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}

Exposure from corn

Corn is a staple in Africa and Latin America and a common vegetable elsewhere, so its share of metal intake depends heavily on how much is eaten. No source in the ledger gives a verified population estimate of lead or cadmium intake from maize grain or sweet corn. A Henan village study estimated that adults ate 13.5 g of corn a day, and several field studies report intake indices, but most rest on dry-weight values applied to as-eaten intake or on concentrations held for integrity problems.^{4Adel S. El-Hassanin, Magdy R. Samak, Gomaa N. Abdel-Rahman, Yahia H. Abu-Sree, Essam M. Saleh · 2020Risk assessment of human exposure to lead and cadmium in maize grains cultivated in soils irrigated either with low-quality water or freshwaterToxicology Reports 7:10-15Read source →}^{7Islam MS, Ahmed MK, Habibullah-Al-Mamun M · 2014Heavy Metals in Cereals and Pulses: Health Implications in BangladeshJournal of Agricultural and Food ChemistryRead source →}^{16Jiang Y, Ma J, Ruan X · 2020Compound health risk assessment of cumulative heavy metal exposure: A case study of a village near a battery factory in Henan Province, ChinaEnvironmental Science: Processes & ImpactsRead source →}

Monitoring results bound the contribution for typical retail corn. With cooked US sweet corn below 4 µg/kg lead and 1 µg/kg mercury in every composite, and median cadmium of 2.6 µg/kg, ordinary retail sweet corn adds little per serving compared with the limits.^{2U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →} Where maize is eaten daily as a staple, the field results above 200 µg/kg lead in Burkina Faso, Bangladesh and contaminated areas are the cases that would matter for intake, but none was turned into a verified exposure estimate.^{3Abatemi-Usman S, Akindele O, Ayanlade A, Perez M, Attahiru I, Norton G, Feldmann J, Krupp E · 2023Trace elements concentrations in soil contaminate corn in the vicinity of a cement-manufacturing plant: potential health implicationsJournal of Exposure Science & Environmental EpidemiologyRead source →}^{4Adel S. El-Hassanin, Magdy R. Samak, Gomaa N. Abdel-Rahman, Yahia H. Abu-Sree, Essam M. Saleh · 2020Risk assessment of human exposure to lead and cadmium in maize grains cultivated in soils irrigated either with low-quality water or freshwaterToxicology Reports 7:10-15Read source →}^{7Islam MS, Ahmed MK, Habibullah-Al-Mamun M · 2014Heavy Metals in Cereals and Pulses: Health Implications in BangladeshJournal of Agricultural and Food ChemistryRead source →}^{11Bazie SR, Compaore MKA, Bande M, Kpoda SD, Meda NSBR, Ouedraogo Kangambega TM, Ilboudo I, Sandwidi BY, Nikiema F, Yakoro A, Bassole IHN, Hien H, Kabre E · 2022Evaluation of metallic trace elements contents in some major raw foodstuffs in Burkina Faso and health risk assessmentScientific ReportsRead source →}

Evidence review and remaining gaps

This assessment covers every source record in the HMI library that names corn or maize, every corn row in the WHO GEMS/Food exports and every corn food in the FDA Total Diet Study; each has a recorded decision based on its content.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}^{2U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →} Thirty literature sources contribute results for maize grain or fresh corn, and values from 13 are held in part because they could not be reconciled with their own methods or tables.^{13Abdullahi N, Dandago MA, Gambo MS, Abubakar SS, Tsoho AU, Idah PG · 2024Seasonal Variation and Uptake Pattern of Heavy Metals in MaizeDutse Journal of Pure and Applied Sciences (DUJOPAS)Read source →}^{20wheat flour marketed in Shanghai City Zuoyin Zhu, Wenbo Guo, Haisheng Cheng, Hanke Zhao, Jie Wang, Mohamed F. Abdallah, Xinli Zhou, Hulong Lei · 2024mycotoxins and heavy metals in rice, maize,Peer-reviewed articleRead source →}^{21Zhang Y, Li X, Kong F · 2026Trace metal pollution and ecological effects on five crops around a typical manganese mining area in Chongqing, ChinaScientific ReportsRead source →}^{22Getu A, Seid Y, Asrade B · 2022Determination of the Level of Heavy Metals in the Selected Cereals from Debre Markos Local Market, Amhara Region, EthiopiaInternational Journal of Analytical ChemistryRead source →}^{23Gholami Z, Mohammadi Rouzbahani M, Payandeh K, Sabzalipour S · 2025Health risk assessment Pb, As and Cr in corn (Zea mays) of Behbahan and Dezful from Khuzestan Province, IranScientific ReportsRead source →}^{24Islam MS, Ahmed MK, Habibullah-Al-Mamun M, Raknuzzaman M · 2015The concentration, source and potential human health risk of heavy metals in the commonly consumed foods in BangladeshEcotoxicology and Environmental SafetyRead source →}^{25Ibrahim UM, Karkarna MZ, Babura SM, Matazu MA, Jibo AM, Umar ML, Aliyu MH · 2024Correlates of Food Contamination by Heavy Metals in Northwest NigeriaEnvironmental Health InsightsRead source →}^{34Masite NS, Ncube S, Madikizela LM, Mtunzi FM, Pakade VE · 2022Trace Metals, Crude Protein, and TGA-FTIR Analysis of Evolved Gas Products in the Thermal Decomposition of Roasted Mopane Worms, Sweet Corn, and PeanutsInternational Journal of Food ScienceRead source →}^{35Meghdad Pirsaheb, Nazir Fattahi, Kiomars Sharafi, Razieh Khamotian, Zahra Atafar · 2015Essential and toxic heavy metals in cereals and agricultural products marketed in Kermanshah, Iran, and human health risk assessmentFood Additives & Contaminants: Part B, SurveillanceRead source →}

The main gaps are origin-linked monitoring of maize grain outside Europe and the Western Pacific, inorganic arsenic in maize, and any study that measures the same corn before and after cleaning, milling or cooking.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →} Two records about Health Canada diaper-rash monographs matched the search but have no readable file; they are unrelated to corn.

References identify the sources used in these answers. The Sources index preserves additional discovery links; inclusion there does not mean a source has been reviewed for this assessment. Corrections, completed searches, new direct evidence and changes in requirements should reopen the relevant answer.

Corn FAQs

What heavy metals are found in corn?

Lead, cadmium, arsenic and mercury are measured most often, and in monitored maize grain and sweet corn most results are below reporting limits.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}^{2U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →} Field studies also report nickel and chromium, which reached about 1,400–1,900 µg/kg in dried maize from Bangladesh fields.^{7Islam MS, Ahmed MK, Habibullah-Al-Mamun M · 2014Heavy Metals in Cereals and Pulses: Health Implications in BangladeshJournal of Agricultural and Food ChemistryRead source →}

How do heavy metals get into corn?

Corn takes up cadmium and nickel from soil, and lead and mercury also reach it from dust and emissions settling on the plant.^{3Abatemi-Usman S, Akindele O, Ayanlade A, Perez M, Attahiru I, Norton G, Feldmann J, Krupp E · 2023Trace elements concentrations in soil contaminate corn in the vicinity of a cement-manufacturing plant: potential health implicationsJournal of Exposure Science & Environmental EpidemiologyRead source →}^{5Li R, Wu H, Ding J, Fu W, Gan L, Li Y · 2017Mercury pollution in vegetables, grains and soils from areas surrounding coal-fired power plantsScientific ReportsRead source →}^{8Gu Q, Yu T, Yang Z, Ji J, Hou Q, Wang L, Wei X, Zhang Q · 2019Prediction and risk assessment of five heavy metals in maize and peanut: a case study of Guangxi, ChinaEnvironmental Toxicology and PharmacologyRead source →} Wastewater irrigation and mining or industrial land raised lead, cadmium, mercury or arsenic in the studies available.^{4Adel S. El-Hassanin, Magdy R. Samak, Gomaa N. Abdel-Rahman, Yahia H. Abu-Sree, Essam M. Saleh · 2020Risk assessment of human exposure to lead and cadmium in maize grains cultivated in soils irrigated either with low-quality water or freshwaterToxicology Reports 7:10-15Read source →}^{14Romero-Crespo P, Jiménez-Oyola S, Salgado-Almeida B, Zambrano-Anchundia J, Goyburo-Chávez C, González-Valoys A, Higueras P · 2023Trace elements in farmland soils and crops, and probabilistic health risk assessment in areas influenced by mining activity in EcuadorEnvironmental Geochemistry and HealthRead source →}^{26Bai AM, Li Q, Li Y, Fan ZX, Li XQ, Tan WH, Cao DY, Kang YJ · 2022Investigation Into Environmental Selenium and Arsenic Levels and Arseniasis Prevalence in an Arsenic-Affected Coal-Burning AreaFrontiers in NutritionRead source →}

Which types of corn have the lowest levels?

For lead, sweet corn measured lowest per kilogram: cooked US sweet corn was below 4 µg/kg in all 27 composites and raw sweet corn medians were below 1.4–10 µg/kg.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}^{2U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →} Maize grain had a European median below 20 µg/kg, and the higher figure largely reflects that grain is dry.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}

Which countries or regions produce corn with the lowest lead?

Among reporting regions, European maize grain had the fewest results above the 200 µg/kg cereal limit (8 of 890), against 24 of 327 in Western Pacific submissions.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →} GEMS/Food does not name the country where corn was grown, so the evidence cannot rank producing countries; growing near industry, wastewater or mines matters more in the field studies.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}^{3Abatemi-Usman S, Akindele O, Ayanlade A, Perez M, Attahiru I, Norton G, Feldmann J, Krupp E · 2023Trace elements concentrations in soil contaminate corn in the vicinity of a cement-manufacturing plant: potential health implicationsJournal of Exposure Science & Environmental EpidemiologyRead source →}^{4Adel S. El-Hassanin, Magdy R. Samak, Gomaa N. Abdel-Rahman, Yahia H. Abu-Sree, Essam M. Saleh · 2020Risk assessment of human exposure to lead and cadmium in maize grains cultivated in soils irrigated either with low-quality water or freshwaterToxicology Reports 7:10-15Read source →}

Do foods made from corn also contain heavy metals?

Corn flour, flakes, popcorn, canned corn and other corn foods are measured separately and have their own pages, so their results are not repeated here.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}^{2U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →} One European study found that infant porridges mixing rice with maize and other grains had lower inorganic arsenic than pure rice porridges (median 10 against 66 µg/kg).^{28Carey M, Donaldson E, Signes-Pastor AJ, Meharg AA · 2018Dilution of rice with other gluten free grains to lower inorganic arsenic in foods for young children in response to European Union regulations provides impetus to setting stricter standardsPLoS ONERead source →}

What do the levels in corn mean for health?

No source in the ledger turned corn concentrations into a verified estimate of population intake, so the evidence cannot say how much corn contributes to lead or cadmium exposure overall. Typical retail sweet corn is low per serving, while maize eaten daily as a staple from contaminated fields is the case where intake could matter.^{2U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →}^{7Islam MS, Ahmed MK, Habibullah-Al-Mamun M · 2014Heavy Metals in Cereals and Pulses: Health Implications in BangladeshJournal of Agricultural and Food ChemistryRead source →}^{11Bazie SR, Compaore MKA, Bande M, Kpoda SD, Meda NSBR, Ouedraogo Kangambega TM, Ilboudo I, Sandwidi BY, Nikiema F, Yakoro A, Bassole IHN, Hien H, Kabre E · 2022Evaluation of metallic trace elements contents in some major raw foodstuffs in Burkina Faso and health risk assessmentScientific ReportsRead source →}

Are there legal limits for heavy metals in corn?

Yes: for maize grain the EU, Codex, China, Hong Kong, Korea and India set 200 µg/kg lead and 100 µg/kg cadmium, and China and Hong Kong set 20 µg/kg total mercury for maize.^{9European Commission · 2023Commission Regulation (EU) 2023/915 of 25 April 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source →}^{10Codex Alimentarius Commission · 1995General Standard for Contaminants and Toxins in Food and Feed (CXS 193-1995)Codex Alimentarius (Joint FAO/WHO Food Standards Programme)Read source →}^{30National Health Commission of the People’s Republic of China, State Administration for Market Regulation · 2022GB 2762-2022 National Food Safety Standard: Maximum Levels of Contaminants in FoodsNational Food Safety Standard GB 2762-2022Read source →}^{31Hong Kong e-Legislation · 2025Hong Kong Cap. 132V Food Adulteration (Metallic Contamination) Regulations, consolidated 5 September 2025Hong Kong e-Legislation Cap. 132VRead source →}^{32Korea Food and Drug Administration · 2012Article 2. Common Standards and Specifications for General FoodsKorean Food CodeRead source →}^{33Food Safety and Standards Authority of India · 2016Food Safety and Standards (Contaminants, toxins and Residues) Third Amendment Regulations, 2016Gazette of India, Extraordinary, Part III, Section 4Read source →} For sweet corn the EU sets 100 µg/kg lead and 20 µg/kg cadmium on a wet-weight basis, and Codex sets 50 µg/kg for each.^{9European Commission · 2023Commission Regulation (EU) 2023/915 of 25 April 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source →}^{10Codex Alimentarius Commission · 1995General Standard for Contaminants and Toxins in Food and Feed (CXS 193-1995)Codex Alimentarius (Joint FAO/WHO Food Standards Programme)Read source →}

Can processing reduce heavy metals in corn?

No study in the library measured the same corn before and after cleaning, husking, milling or cooking, so no reduction can be stated. Drying raises the concentration per kilogram because water is removed, which is why dried-grain results look higher than sweet corn as eaten.^{3Abatemi-Usman S, Akindele O, Ayanlade A, Perez M, Attahiru I, Norton G, Feldmann J, Krupp E · 2023Trace elements concentrations in soil contaminate corn in the vicinity of a cement-manufacturing plant: potential health implicationsJournal of Exposure Science & Environmental EpidemiologyRead source →}^{15Saleem M, Wang Y, Pierce D, Sens DA, Somji S, Garrett SH · 2025Concentration and Potential Non-Carcinogenic and Carcinogenic Health Risk Assessment of Metals in Locally Grown VegetablesFoodsRead source →}

Does cooking corn get rid of heavy metals?

Heat does not destroy metals, and no study measured the same corn before and after cooking. Cooked sweet corn in monitoring had lead and cadmium similar to raw sweet corn from the same regions, mostly below reporting limits.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}^{2U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →}

Does corn contain inorganic arsenic like rice?

Much less is known: only 12 maize results were speciated for inorganic arsenic, and 2 were detected, at 8 and 310 µg/kg.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →} Total arsenic in monitored maize grain had a median below 12–15 µg/kg, but field maize from Bangladesh and arsenic-affected areas of China and Ecuador was far higher.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}^{7Islam MS, Ahmed MK, Habibullah-Al-Mamun M · 2014Heavy Metals in Cereals and Pulses: Health Implications in BangladeshJournal of Agricultural and Food ChemistryRead source →}^{14Romero-Crespo P, Jiménez-Oyola S, Salgado-Almeida B, Zambrano-Anchundia J, Goyburo-Chávez C, González-Valoys A, Higueras P · 2023Trace elements in farmland soils and crops, and probabilistic health risk assessment in areas influenced by mining activity in EcuadorEnvironmental Geochemistry and HealthRead source →}^{26Bai AM, Li Q, Li Y, Fan ZX, Li XQ, Tan WH, Cao DY, Kang YJ · 2022Investigation Into Environmental Selenium and Arsenic Levels and Arseniasis Prevalence in an Arsenic-Affected Coal-Burning AreaFrontiers in NutritionRead source →}

Is corn lower in arsenic and cadmium than rice?

In the same contaminated areas, maize carried less than rice: about a third of the mercury near Chinese coal-fired power plants and 260 against 460 µg/kg cadmium near Chengdu.^{5Li R, Wu H, Ding J, Fu W, Gan L, Li Y · 2017Mercury pollution in vegetables, grains and soils from areas surrounding coal-fired power plantsScientific ReportsRead source →}^{6Liu Q, Li X, He L · 2022Health risk assessment of heavy metals in soils and food crops from a coexist area of heavily industrialized and intensively cropping in the Chengdu Plain, Sichuan, ChinaFrontiers in ChemistryRead source →} Maize lead was similar to rice in Chengdu (290 against 300 µg/kg), so the advantage is not universal.^{6Liu Q, Li X, He L · 2022Health risk assessment of heavy metals in soils and food crops from a coexist area of heavily industrialized and intensively cropping in the Chengdu Plain, Sichuan, ChinaFrontiers in ChemistryRead source →}

Is corn a concern for babies and children?

Infant cereals and baby foods containing corn are covered on their own pages; on this page, retail sweet corn was low in lead, with every cooked US composite below 4 µg/kg.^{2U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →} Maize from contaminated fields would matter most where it is a daily staple for children, and the evidence has no child-specific exposure estimate.^{3Abatemi-Usman S, Akindele O, Ayanlade A, Perez M, Attahiru I, Norton G, Feldmann J, Krupp E · 2023Trace elements concentrations in soil contaminate corn in the vicinity of a cement-manufacturing plant: potential health implicationsJournal of Exposure Science & Environmental EpidemiologyRead source →}^{4Adel S. El-Hassanin, Magdy R. Samak, Gomaa N. Abdel-Rahman, Yahia H. Abu-Sree, Essam M. Saleh · 2020Risk assessment of human exposure to lead and cadmium in maize grains cultivated in soils irrigated either with low-quality water or freshwaterToxicology Reports 7:10-15Read source →}

Is sweet corn safer than field corn?

Sweet corn had lower lead per kilogram in monitoring, but it is mostly water and is judged against a lower lead limit (100 against 200 µg/kg in the EU).^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}^{2U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →}^{9European Commission · 2023Commission Regulation (EU) 2023/915 of 25 April 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source →} Both forms grown near industry, wastewater or mines can carry more metal, so where the corn grew matters more than the type.^{3Abatemi-Usman S, Akindele O, Ayanlade A, Perez M, Attahiru I, Norton G, Feldmann J, Krupp E · 2023Trace elements concentrations in soil contaminate corn in the vicinity of a cement-manufacturing plant: potential health implicationsJournal of Exposure Science & Environmental EpidemiologyRead source →}^{4Adel S. El-Hassanin, Magdy R. Samak, Gomaa N. Abdel-Rahman, Yahia H. Abu-Sree, Essam M. Saleh · 2020Risk assessment of human exposure to lead and cadmium in maize grains cultivated in soils irrigated either with low-quality water or freshwaterToxicology Reports 7:10-15Read source →}^{5Li R, Wu H, Ding J, Fu W, Gan L, Li Y · 2017Mercury pollution in vegetables, grains and soils from areas surrounding coal-fired power plantsScientific ReportsRead source →}

Has lead in corn been falling?

In European maize grain submitted to GEMS/Food, 4 of 233 results from 2001–2007 and 4 of 257 from 2008–2013 exceeded 200 µg/kg lead, against none of 400 from 2014–2020.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →} Coverage changed over the years, so this is a monitoring pattern rather than a fixed panel of farms.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}

Is imported corn higher in metals than locally grown corn?

In European submissions, imported maize grain had lead and cadmium similar to domestic grain, and imported sweet corn had lower cadmium (median below 2.4 against 2.6–4 µg/kg).^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →} The export does not name the producing country, so this cannot identify which origins are higher.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}

Is corn grown near mines or factories higher in metals?

Yes, in every such study available: downwind of a cement plant, beside coal-fired power plants, near a battery plant, on wastewater-irrigated fields and in mining areas, corn carried more lead, mercury, cadmium or arsenic than control or market corn.^{3Abatemi-Usman S, Akindele O, Ayanlade A, Perez M, Attahiru I, Norton G, Feldmann J, Krupp E · 2023Trace elements concentrations in soil contaminate corn in the vicinity of a cement-manufacturing plant: potential health implicationsJournal of Exposure Science & Environmental EpidemiologyRead source →}^{4Adel S. El-Hassanin, Magdy R. Samak, Gomaa N. Abdel-Rahman, Yahia H. Abu-Sree, Essam M. Saleh · 2020Risk assessment of human exposure to lead and cadmium in maize grains cultivated in soils irrigated either with low-quality water or freshwaterToxicology Reports 7:10-15Read source →}^{5Li R, Wu H, Ding J, Fu W, Gan L, Li Y · 2017Mercury pollution in vegetables, grains and soils from areas surrounding coal-fired power plantsScientific ReportsRead source →}^{14Romero-Crespo P, Jiménez-Oyola S, Salgado-Almeida B, Zambrano-Anchundia J, Goyburo-Chávez C, González-Valoys A, Higueras P · 2023Trace elements in farmland soils and crops, and probabilistic health risk assessment in areas influenced by mining activity in EcuadorEnvironmental Geochemistry and HealthRead source →}^{16Jiang Y, Ma J, Ruan X · 2020Compound health risk assessment of cumulative heavy metal exposure: A case study of a village near a battery factory in Henan Province, ChinaEnvironmental Science: Processes & ImpactsRead source →}^{17Bedoya-Perales NS, Escobedo-Pacheco E, Maus D, Neimaier A, Pumi G · 2023Dataset of metals and metalloids in food crops and soils sampled across the mining region of Moquegua in PeruScientific DataRead source →} The size of the increase varied widely between sites and metals.^{3Abatemi-Usman S, Akindele O, Ayanlade A, Perez M, Attahiru I, Norton G, Feldmann J, Krupp E · 2023Trace elements concentrations in soil contaminate corn in the vicinity of a cement-manufacturing plant: potential health implicationsJournal of Exposure Science & Environmental EpidemiologyRead source →}^{4Adel S. El-Hassanin, Magdy R. Samak, Gomaa N. Abdel-Rahman, Yahia H. Abu-Sree, Essam M. Saleh · 2020Risk assessment of human exposure to lead and cadmium in maize grains cultivated in soils irrigated either with low-quality water or freshwaterToxicology Reports 7:10-15Read source →}^{5Li R, Wu H, Ding J, Fu W, Gan L, Li Y · 2017Mercury pollution in vegetables, grains and soils from areas surrounding coal-fired power plantsScientific ReportsRead source →}

How can I tell whether a corn metal test is good enough?

Check that the quantification limit sits well below the limit for the form tested, for example below 20 µg/kg cadmium for sweet corn in the EU, and that the result states the form and basis.^{9European Commission · 2023Commission Regulation (EU) 2023/915 of 25 April 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006Official Journal of the European UnionRead source →} The FDA reported cooked corn with limits of 4 µg/kg lead, 3 µg/kg arsenic and 1 µg/kg mercury, a useful benchmark for sensitivity.^{2U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →}

References

Works cited on this page, in citation-number order. See Sources for this page’s source inventory. Each title links to a source record with bibliographic details, reported findings, and document provenance.

GEMS/Food Contaminants database heavy-metal exportsWorld Health Organization · GEMS/Food Contamination Monitoring and Assessment Programme · 2026 · extranet.who.intDataset
FY2018-FY2020 TDS Elements Analytical ResultsU.S. Food and Drug Administration · FDA Total Diet Study · 2022 · www.fda.govDataset
Trace elements concentrations in soil contaminate corn in the vicinity of a cement-manufacturing plant: potential health implicationsAbatemi-Usman S, Akindele O, Ayanlade A, Perez M, Attahiru I, Norton G, et al. · Journal of Exposure Science & Environmental Epidemiology · 2023 · doi.org/10.1038/s41370-023-00548-8Peer-reviewed
Risk assessment of human exposure to lead and cadmium in maize grains cultivated in soils irrigated either with low-quality water or freshwaterAdel S. El-Hassanin, Magdy R. Samak, Gomaa N. Abdel-Rahman, Yahia H. Abu-Sree, and Essam M. Saleh · Toxicology Reports 7:10-15 · 2020 · doi.org/10.1016/j.toxrep.2019.11.018Peer-reviewed
Mercury pollution in vegetables, grains and soils from areas surrounding coal-fired power plantsLi R, Wu H, Ding J, Fu W, Gan L, and Li Y · Scientific Reports · 2017 · doi.org/10.1038/srep46545Peer-reviewed
Health risk assessment of heavy metals in soils and food crops from a coexist area of heavily industrialized and intensively cropping in the Chengdu Plain, Sichuan, ChinaLiu Q, Li X, and He L · Frontiers in Chemistry · 2022 · doi.org/10.3389/fchem.2022.988587Peer-reviewed
Heavy Metals in Cereals and Pulses: Health Implications in BangladeshIslam MS, Ahmed MK, and Habibullah-Al-Mamun M · Journal of Agricultural and Food Chemistry · 2014 · doi.org/10.1021/jf502486qPeer-reviewed
Prediction and risk assessment of five heavy metals in maize and peanut: a case study of Guangxi, ChinaGu Q, Yu T, Yang Z, Ji J, Hou Q, Wang L, et al. · Environmental Toxicology and Pharmacology · 2019 · doi.org/10.1016/j.etap.2019.103199Peer-reviewed
Commission Regulation (EU) 2023/915 of 25 April 2023 on maximum levels for certain contaminants in food and repealing Regulation (EC) No 1881/2006European Commission · Official Journal of the European Union · 2023 · eur-lex.europa.euRegulation
General Standard for Contaminants and Toxins in Food and Feed (CXS 193-1995)Codex Alimentarius Commission · Codex Alimentarius (Joint FAO/WHO Food Standards Programme) · 1995 · www.fao.orgGovernment
Evaluation of metallic trace elements contents in some major raw foodstuffs in Burkina Faso and health risk assessmentBazie SR, Compaore MKA, Bande M, Kpoda SD, Meda NSBR, Ouedraogo Kangambega TM, et al. · Scientific Reports · 2022 · doi.org/10.1038/s41598-022-08470-zPeer-reviewed
Spatial distribution and risk assessment of fluorine and cadmium in rice, corn, and wheat grains in most karst regions of Guizhou province, ChinaLi X, Zhou L, Zhang C, Li D, Wang Z, Sun D, et al. · Frontiers in Nutrition · 2022 · doi.org/10.3389/fnut.2022.1014147Peer-reviewed
Seasonal Variation and Uptake Pattern of Heavy Metals in MaizeAbdullahi N, Dandago MA, Gambo MS, Abubakar SS, Tsoho AU, and Idah PG · Dutse Journal of Pure and Applied Sciences (DUJOPAS) · 2024 · doi.org/10.4314/dujopas.v10i1a.9Peer-reviewed
Trace elements in farmland soils and crops, and probabilistic health risk assessment in areas influenced by mining activity in EcuadorRomero-Crespo P, Jiménez-Oyola S, Salgado-Almeida B, Zambrano-Anchundia J, Goyburo-Chávez C, González-Valoys A, et al. · Environmental Geochemistry and Health · 2023 · doi.org/10.1007/s10653-023-01514-xPeer-reviewed
Concentration and Potential Non-Carcinogenic and Carcinogenic Health Risk Assessment of Metals in Locally Grown VegetablesSaleem M, Wang Y, Pierce D, Sens DA, Somji S, and Garrett SH · Foods · 2025 · doi.org/10.3390/foods14132264Peer-reviewed
Compound health risk assessment of cumulative heavy metal exposure: A case study of a village near a battery factory in Henan Province, ChinaJiang Y, Ma J, and Ruan X · Environmental Science: Processes & Impacts · 2020 · doi.org/10.1039/D0EM00104JPeer-reviewed
Dataset of metals and metalloids in food crops and soils sampled across the mining region of Moquegua in PeruBedoya-Perales NS, Escobedo-Pacheco E, Maus D, Neimaier A, and Pumi G · Scientific Data · 2023 · doi.org/10.1038/s41597-023-02363-0Peer-reviewed
Heavy metal synergistic pollution risk assessment in the soil-crop system of the Nanyang BasinLiu Z, Wang L, Yan M, Tian Y, Ma B, and Xie Q · Scientific Reports · 2025 · doi.org/10.1038/s41598-025-05236-1Peer-reviewed
Arsenic and cadmium concentrations in legumes and cereals grown in the North Central Province, Sri Lanka and assessment of their health riskEdirisinghe EMRKB and Jinadasa BKKK · International Journal of Food Contamination 6:3 · 2019 · doi.org/10.1186/s40550-019-0073-xPeer-reviewed
mycotoxins and heavy metals in rice, maize,wheat flour marketed in Shanghai City Zuoyin Zhu, Wenbo Guo, Haisheng Cheng, Hanke Zhao, Jie Wang, Mohamed F. Abdallah, et al. · Peer-reviewed article · 2024 · doi.org/10.1016/j.jhazmat.2024.134695Peer-reviewed
Trace metal pollution and ecological effects on five crops around a typical manganese mining area in Chongqing, ChinaZhang Y, Li X, and Kong F · Scientific Reports · 2026 · doi.org/10.1038/s41598-026-37535-6Peer-reviewed
Determination of the Level of Heavy Metals in the Selected Cereals from Debre Markos Local Market, Amhara Region, EthiopiaGetu A, Seid Y, and Asrade B · International Journal of Analytical Chemistry · 2022 · doi.org/10.1155/2022/7146439Peer-reviewed
Health risk assessment Pb, As and Cr in corn (Zea mays) of Behbahan and Dezful from Khuzestan Province, IranGholami Z, Mohammadi Rouzbahani M, Payandeh K, and Sabzalipour S · Scientific Reports · 2025 · doi.org/10.1038/s41598-025-89281-wPeer-reviewed
The concentration, source and potential human health risk of heavy metals in the commonly consumed foods in BangladeshIslam MS, Ahmed MK, Habibullah-Al-Mamun M, and Raknuzzaman M · Ecotoxicology and Environmental Safety · 2015 · doi.org/10.1016/j.ecoenv.2015.09.022Peer-reviewed
Correlates of Food Contamination by Heavy Metals in Northwest NigeriaIbrahim UM, Karkarna MZ, Babura SM, Matazu MA, Jibo AM, Umar ML, et al. · Environmental Health Insights · 2024 · doi.org/10.1177/11786302241301700Peer-reviewed
Investigation Into Environmental Selenium and Arsenic Levels and Arseniasis Prevalence in an Arsenic-Affected Coal-Burning AreaBai AM, Li Q, Li Y, Fan ZX, Li XQ, Tan WH, et al. · Frontiers in Nutrition · 2022 · doi.org/10.3389/fnut.2022.922481Peer-reviewed
MERCOSUR/GMC/RES. No. 12/11: Reglamento Tecnico MERCOSUR sobre Limites Maximos de Contaminantes Inorganicos en AlimentosMERCOSUR Grupo Mercado Comun · MERCOSUR/GMC/RES. No. 12/11 · 2011Regulation
Dilution of rice with other gluten free grains to lower inorganic arsenic in foods for young children in response to European Union regulations provides impetus to setting stricter standardsCarey M, Donaldson E, Signes-Pastor AJ, and Meharg AA · PLoS ONE · 2018 · doi.org/10.1371/journal.pone.0194700Peer-reviewed
A rapid magnetic-based purification of Cd2+ and Pb2+ prior to portable electrochemical determination for grainTian W, Zhou M, Liu Y, Wu Y, Zhang J, Chen X, et al. · Food Chemistry: X · 2023 · doi.org/10.1016/j.fochx.2023.100636Peer-reviewed
GB 2762-2022 National Food Safety Standard: Maximum Levels of Contaminants in FoodsNational Health Commission of the People’s Republic of China and State Administration for Market Regulation · National Food Safety Standard GB 2762-2022 · 2022 · www.nhc.gov.cnRegulation
Hong Kong Cap. 132V Food Adulteration (Metallic Contamination) Regulations, consolidated 5 September 2025Hong Kong e-Legislation · 2025 · www.elegislation.gov.hkRegulation
Article 2. Common Standards and Specifications for General FoodsKorea Food and Drug Administration · Korean Food Code · 2012Regulation
Food Safety and Standards (Contaminants, toxins and Residues) Third Amendment Regulations, 2016Food Safety and Standards Authority of India · Gazette of India, Extraordinary, Part III, Section 4 · 2016Regulation
Trace Metals, Crude Protein, and TGA-FTIR Analysis of Evolved Gas Products in the Thermal Decomposition of Roasted Mopane Worms, Sweet Corn, and PeanutsMasite NS, Ncube S, Madikizela LM, Mtunzi FM, and Pakade VE · International Journal of Food Science · 2022 · doi.org/10.1155/2022/1509569Peer-reviewed
Essential and toxic heavy metals in cereals and agricultural products marketed in Kermanshah, Iran, and human health risk assessmentMeghdad Pirsaheb, Nazir Fattahi, Kiomars Sharafi, Razieh Khamotian, and Zahra Atafar · Food Additives & Contaminants: Part B, Surveillance · 2015 · doi.org/10.1080/19393210.2015.1099570Peer-reviewed

Sources

Browse Corn Sources for sources cited on this page and additional discovery candidates. The searchable index distinguishes verified citation use from discovery relationships whose relevance has not been established.

Update history

22 October 2026: Rebuilt from every corn record in the library: WHO GEMS/Food and FDA monitoring results for maize grain and sweet corn, thirty field, market and contaminated-site studies, references by form and basis, verified limits and stage-led controls.

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Heavy metals in Corn

Corn overview

What counts as corn

Heavy metal contamination profile of corn

How metals reach corn

Which forms and regions measured lower

Drying, cooking and processing

Mitigation from field to lot

Trade-offs and limits of controls

Testing corn for metals

Buying and verifying corn

Exposure from corn

Evidence review and remaining gaps

Corn FAQs

References

Sources

Update history

Referenced by

Graph View

Heavy metals in Corn

Corn overview

What counts as corn

Heavy metal contamination profile of corn

How metals reach corn

Which forms and regions measured lower

Drying, cooking and processing

Mitigation from field to lot

Trade-offs and limits of controls

Testing corn for metals

Buying and verifying corn

Exposure from corn

Evidence review and remaining gaps

Corn FAQs

References

Sources

Update history

Related ingredients

Referenced by

Graph View