Heavy metals in Leafy greens

Leafy greens overview

Cadmium is the metal that most often decides a leafy-green question, and the leaf type matters more than any other single factor in the monitoring data.^{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 →} Across more than 2,200 WHO GEMS/Food spinach results the median was about 41 µg/kg fresh weight, against 19–20 µg/kg for leaf lettuce, 11–12 µg/kg for head lettuce and 2–4 µg/kg for head cabbage.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →} The FDA Total Diet Study found the same order in US market composites from 2018 to 2020: spinach 200, leaf lettuce 57, iceberg lettuce 27 and cabbage 5.1 µg/kg as medians.^{2U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →} European monitoring summarised by EFSA gave spinach a mean of 61.5 µg/kg and other leafy vegetables 23.1 µg/kg, with 3.9% of spinach samples above the EU limit.^{4EFSA Panel on Contaminants in the Food Chain (CONTAM) · 2009Scientific Opinion of the Panel on Contaminants in the Food Chain on a request from the European Commission on cadmium in foodThe EFSA JournalRead source →}

Lead is usually low in routinely monitored retail leaves.^{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 →} Most head lettuce and cabbage results in GEMS/Food were below detection, most FDA lettuce and cabbage composites were below a 4 µg/kg reporting limit, and EFSA’s European leafy-vegetable median was 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 →9EFSA Panel on Contaminants in the Food Chain (CONTAM) · 2010Scientific Opinion on Lead in FoodEFSA Journal 2010;8(4):1570Read source →} The EU limits are 0.30 mg/kg (300 µg/kg) lead for leaf vegetables and 0.10 mg/kg cadmium, raised to 0.20 mg/kg for spinach and similar leaves and fresh herbs.^{8European 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 →}

Field studies near mining, smelting, coal power plants, wastewater irrigation or heavy traffic report leaves tens to hundreds of times more contaminated than market monitoring.^{3Naser HM, Rahman MZ, Sultana S, Quddus MA, Hossain MA · 2018Heavy metal accumulation in leafy vegetables grown in industrial areas under varying levels of pollutionBangladesh Journal of Agricultural ResearchRead source →6Li 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 →7Adhikari S, Struwig M · 2024Concentrations and health risks of selected elements in leafy vegetables: a comparison between roadside open-air markets and large stores in Johannesburg, South AfricaNot reportedRead source →10Rossini-Oliva S, López Nuñez R · 2024Is it healthy urban agriculture? Human exposure to potentially toxic elements in urban gardens from Andalusia, SpainEnvironmental Science and Pollution ResearchRead source →} Many of those studies report on a dry-weight basis, which by itself raises concentrations about ten-fold, and several fail checks against their own methods, so the page shows them without comparing them.^{11Cherfi A, Abdoun S, Gaci O · 2014Food survey: Levels and potential health risks of chromium, lead, zinc and copper content in fruits and vegetables consumed in AlgeriaFood and Chemical ToxicologyRead source →12Sultana R, Tanvir RU, Hussain KA, Chamon AS, Mondol MN · 2022Heavy Metals in Commonly Consumed Root and Leafy Vegetables in Dhaka City, Bangladesh, and Assessment of Associated Public Health RisksEnvironmental Systems ResearchRead source →13Liu F, Yang Z, Li Q, Li T · 2023Enrichment Characteristics and Health Risk Assessment of Heavy Metals in Soil-Crop SystemsKSCE Journal of Civil EngineeringRead source →} For a buyer the supported priorities are the growing site and irrigation water, the leaf type, and lot results for cadmium and lead reported on a fresh-weight basis.^{6Li 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 →8European 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 →14Clair-Caliot G, Marks SJ, Hug SJ, Bretzler A, N’guessan ND, Tihe SFK, Lalanne F · 2021Uptake of Arsenic by Irrigated Vegetables and Cooked Food Products in Burkina FasoFrontiers in WaterRead source →}

Leafy greens and their preparations

This page covers edible leaves eaten as vegetables, each kept as its own material: spinach, leaf, head and romaine lettuce, head cabbage, Chinese cabbage, pak choi, kale, chard, amaranth, water spinach, mustard greens, watercress, lamb’s lettuce, rocket and leafy herbs such as coriander, parsley, mint and dill.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →15Veronica Martin-Leon, Carmen Rubio, Angel Rodriguez-Hernandez, Manuel Zumbado, Andrea Acosta-Dacal, Luis Alberto Henriquez-Hernandez, Luis D. Boada, Maria del Mar Travieso-Aja, Octavio P. Luzardo · 2023Evaluation of essential, toxic and potentially toxic elements in leafy vegetables grown in the Canary IslandsToxicsRead source →16Centre for Food Safety (Hong Kong) · 2013The First Hong Kong Total Diet Study: Metallic ContaminantsCentre for Food Safety, Food and Environmental Hygiene Department, Government of the Hong Kong Special Administrative RegionRead source →} Cooked, frozen, canned, fermented and dried leaves are kept apart from raw leaves, because preparation changes water content and can add or remove metals.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →14Clair-Caliot G, Marks SJ, Hug SJ, Bretzler A, N’guessan ND, Tihe SFK, Lalanne F · 2021Uptake of Arsenic by Irrigated Vegetables and Cooked Food Products in Burkina FasoFrontiers in WaterRead source →}

The basis of a result matters as much as the leaf. Fresh leaves are mostly water, about 92% in the Algerian spinach and salad samples, so a dry-weight result is roughly ten times the fresh-weight value for the same leaf.^{11Cherfi A, Abdoun S, Gaci O · 2014Food survey: Levels and potential health risks of chromium, lead, zinc and copper content in fruits and vegetables consumed in AlgeriaFood and Chemical ToxicologyRead source →} The page never converts between fresh and dry weight, and results whose basis is not stated stay separate.^{17Kim BF, Lupolt SN, Santo RE, Bachman G, Zhu X, Yang T, Fukagawa NK, Richardson ML, Green C, Phillips KM, Nachman KE · 2024Nutrients and non-essential metals in darkibor kale grown at urban and rural farms: a pilot studyPLOS ONERead source →11Cherfi A, Abdoun S, Gaci O · 2014Food survey: Levels and potential health risks of chromium, lead, zinc and copper content in fruits and vegetables consumed in AlgeriaFood and Chemical ToxicologyRead source →} Seaweed sold as sea lettuce, tea and medicinal herb leaves, mixed baby foods that contain spinach, Brussels sprouts, roots and stems are outside this scope.^{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 →18Baxter M, Brereton N · 2015Total Diet Study of metals and other elements in foodFood and Environment Research Agency report for the UK Food Standards Agency, Fera report 15/06, project FS102081Read source →}

Heavy metal contamination profile of leafy greens

The table holds every leafy-green result extracted from 98 sampling families, including WHO GEMS/Food submissions summarised by leaf, region and sampling type, the FDA and UK total diet studies, Hong Kong’s total diet study and every field and market survey in the library.^{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 →15Veronica Martin-Leon, Carmen Rubio, Angel Rodriguez-Hernandez, Manuel Zumbado, Andrea Acosta-Dacal, Luis Alberto Henriquez-Hernandez, Luis D. Boada, Maria del Mar Travieso-Aja, Octavio P. Luzardo · 2023Evaluation of essential, toxic and potentially toxic elements in leafy vegetables grown in the Canary IslandsToxicsRead source →16Centre for Food Safety (Hong Kong) · 2013The First Hong Kong Total Diet Study: Metallic ContaminantsCentre for Food Safety, Food and Environmental Hygiene Department, Government of the Hong Kong Special Administrative RegionRead source →18Baxter M, Brereton N · 2015Total Diet Study of metals and other elements in foodFood and Environment Research Agency report for the UK Food Standards Agency, Fera report 15/06, project FS102081Read source →} Each row is one statistic for one leaf, group and metal on its stated basis; ratings place a mean, median or sample value against a pooled HMI reference for the same leaf and basis.^{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 →17Kim BF, Lupolt SN, Santo RE, Bachman G, Zhu X, Yang T, Fukagawa NK, Richardson ML, Green C, Phillips KM, Nachman KE · 2024Nutrients and non-essential metals in darkibor kale grown at urban and rural farms: a pilot studyPLOS ONERead source →}

Non-detects stay as intervals from zero to 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 →2U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →} Rows that fail a check against their own paper, and values read from a figure rather than printed, stay visible with the reason and are not compared.^{7Adhikari S, Struwig M · 2024Concentrations and health risks of selected elements in leafy vegetables: a comparison between roadside open-air markets and large stores in Johannesburg, South AfricaNot reportedRead source →12Sultana R, Tanvir RU, Hussain KA, Chamon AS, Mondol MN · 2022Heavy Metals in Commonly Consumed Root and Leafy Vegetables in Dhaka City, Bangladesh, and Assessment of Associated Public Health RisksEnvironmental Systems ResearchRead source →13Liu F, Yang Z, Li Q, Li T · 2023Enrichment Characteristics and Health Risk Assessment of Heavy Metals in Soil-Crop SystemsKSCE Journal of Civil EngineeringRead source →}