Heavy metals in Catfish

Quick read

Catfish in the HMI library has 210 reported results for lead, cadmium, total arsenic, inorganic arsenic, total mercury, methylmercury, nickel, chromium, aluminium, uranium, Cu, Fe, Zn, Se, organotin_DBT, organotin_DPT, organotin_MBT, organotin_MPT, organotin_TBT and organotin_TPT from 21 sources.^{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 →}^{3Islam 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 →}^{4Simionov IA, Calmuc M, Iticescu C, Calmuc V, Georgescu PL, Faggio C, Petrea SM · 2023Human health risk assessment of potentially toxic elements and microplastics accumulation in products from the Danube River Basin fish marketEnvironmental Toxicology and PharmacologyRead source →}^{5Sirisangarunroj P, Monboonpitak N, Karnpanit W, Sridonpai P, Singhato A, Laitip N, Ornthai N, Yafa C, Judprasong K · 2023Toxic Heavy Metals and Their Risk Assessment of Exposure in Selected Freshwater and Marine Fish in ThailandFoods 2023, 12, 3967Read source →}^{6Unknown authors · 2015Variability in Levels of Heavy Metals in Water and FishPeer-reviewed articleRead source →}

Metals measured:
Lead, cadmium, total arsenic, inorganic arsenic, total mercury and methylmercury and others, in 210 results from 21 sources.^{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 →}^{3Islam 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 →}^{4Simionov IA, Calmuc M, Iticescu C, Calmuc V, Georgescu PL, Faggio C, Petrea SM · 2023Human health risk assessment of potentially toxic elements and microplastics accumulation in products from the Danube River Basin fish marketEnvironmental Toxicology and PharmacologyRead source →}
Main drivers:
Form, basis and where the catfish was sampled; reporting limits decide how many results are non-detects.^{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 →}^{3Islam 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 →}^{4Simionov IA, Calmuc M, Iticescu C, Calmuc V, Georgescu PL, Faggio C, Petrea SM · 2023Human health risk assessment of potentially toxic elements and microplastics accumulation in products from the Danube River Basin fish marketEnvironmental Toxicology and PharmacologyRead source →}
Practical framing:
Ask for lot results with a quantification limit well below the limit that applies in the destination market.^{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 →}^{3Islam 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 →}^{4Simionov IA, Calmuc M, Iticescu C, Calmuc V, Georgescu PL, Faggio C, Petrea SM · 2023Human health risk assessment of potentially toxic elements and microplastics accumulation in products from the Danube River Basin fish marketEnvironmental Toxicology and PharmacologyRead source →}

Catfish overview

Catfish in the HMI library has 210 reported results for lead, cadmium, total arsenic, inorganic arsenic, total mercury, methylmercury, nickel, chromium, aluminium, uranium, Cu, Fe, Zn, Se, organotin_DBT, organotin_DPT, organotin_MBT, organotin_MPT, organotin_TBT and organotin_TPT from 21 sources.^{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 →}^{3Islam 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 →}^{4Simionov IA, Calmuc M, Iticescu C, Calmuc V, Georgescu PL, Faggio C, Petrea SM · 2023Human health risk assessment of potentially toxic elements and microplastics accumulation in products from the Danube River Basin fish marketEnvironmental Toxicology and PharmacologyRead source →}^{5Sirisangarunroj P, Monboonpitak N, Karnpanit W, Sridonpai P, Singhato A, Laitip N, Ornthai N, Yafa C, Judprasong K · 2023Toxic Heavy Metals and Their Risk Assessment of Exposure in Selected Freshwater and Marine Fish in ThailandFoods 2023, 12, 3967Read source →}^{6Unknown authors · 2015Variability in Levels of Heavy Metals in Water and FishPeer-reviewed articleRead source →} WHO GEMS/Food submissions reported lead in catfish, as sold from 105 results in 3 reporting regions, with a subgroup median of 6.6 µg/kg.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →} In the US Total Diet Study, catfish, oil had a median lead result below 4 µg/kg across 27 composites from 2017–2020.^{2U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →}

Across 3 other studies of ordinary farms and markets, reported lead means and medians on a dry-weight basis ranged from 289 µg/kg (authors 2021) to 18,400 µg/kg (authors 2015).^{6Unknown authors · 2015Variability in Levels of Heavy Metals in Water and FishPeer-reviewed articleRead source →}^{7Unknown authors · 2021International Journal of Fisheries and Aquatic Studies 2021; 9(4): 230-233Peer-reviewed articleRead source →} For cadmium, 2 studies on an as-sold or fresh-weight basis reported means and medians from 0.6 µg/kg (Spungen et al. 2024) to 3 µg/kg (Simionov et al. 2023).^{4Simionov IA, Calmuc M, Iticescu C, Calmuc V, Georgescu PL, Faggio C, Petrea SM · 2023Human health risk assessment of potentially toxic elements and microplastics accumulation in products from the Danube River Basin fish marketEnvironmental Toxicology and PharmacologyRead source →}^{8Spungen JH, et al. · 2024Infants’ and young children’s dietary exposures to lead and cadmium: FDA total diet study 2018-2020Food Additives & Contaminants: Part ARead source →}

For a buyer the practical points are the form bought, the basis a result is reported on, where the catfish came from and the laboratory’s reporting limit. Testing finds contamination but does not remove it.

What counts as catfish

This page covers catfish in 3 forms kept separate in every comparison: catfish, as sold (198 results), catfish, oil (9 results) and catfish, cooked (3 results).^{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 →}^{3Islam 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 →}^{4Simionov IA, Calmuc M, Iticescu C, Calmuc V, Georgescu PL, Faggio C, Petrea SM · 2023Human health risk assessment of potentially toxic elements and microplastics accumulation in products from the Danube River Basin fish marketEnvironmental Toxicology and PharmacologyRead source →}^{5Sirisangarunroj P, Monboonpitak N, Karnpanit W, Sridonpai P, Singhato A, Laitip N, Ornthai N, Yafa C, Judprasong K · 2023Toxic Heavy Metals and Their Risk Assessment of Exposure in Selected Freshwater and Marine Fish in ThailandFoods 2023, 12, 3967Read source →}^{6Unknown authors · 2015Variability in Levels of Heavy Metals in Water and FishPeer-reviewed articleRead source →}

Results stay on the basis each source reports: as sold or fresh weight, dry weight, or unstated. Dry-weight, as-sold and unstated results are never pooled, and no moisture conversion is applied.

Heavy metal contamination profile of catfish

The table holds every extracted catfish result: one row for each statistic a source reports for a form, group and metal, 210 rows in all, grouped by metal and form; percentiles, ranges and maxima for the same samples as a mean or median are shown on that row.^{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 →}^{3Islam 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 →}^{4Simionov IA, Calmuc M, Iticescu C, Calmuc V, Georgescu PL, Faggio C, Petrea SM · 2023Human health risk assessment of potentially toxic elements and microplastics accumulation in products from the Danube River Basin fish marketEnvironmental Toxicology and PharmacologyRead source →}^{5Sirisangarunroj P, Monboonpitak N, Karnpanit W, Sridonpai P, Singhato A, Laitip N, Ornthai N, Yafa C, Judprasong K · 2023Toxic Heavy Metals and Their Risk Assessment of Exposure in Selected Freshwater and Marine Fish in ThailandFoods 2023, 12, 3967Read source →}^{6Unknown authors · 2015Variability in Levels of Heavy Metals in Water and FishPeer-reviewed articleRead source →} Monitoring medians are HMI calculations from individual submissions; 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 →}

9 rows can be rated against an HMI reference for the same form and basis, 10 rows have a direct same-study comparison, and the rest stay unrated with the reason recorded. 10 values from 2 sources failed a check against their own source and are shown but not compared.^{4Simionov IA, Calmuc M, Iticescu C, Calmuc V, Georgescu PL, Faggio C, Petrea SM · 2023Human health risk assessment of potentially toxic elements and microplastics accumulation in products from the Danube River Basin fish marketEnvironmental Toxicology and PharmacologyRead source →}^{9Sawe S, Amasi A, Wynants M · 2023Assessment of Potentially Toxic Metals in Fish from Lake Manyara, Northern TanzaniaBulletin of Environmental Contamination and ToxicologyRead source →}

Comparison methods and scope

Each row is one statistic a source reports for one form of catfish, group and metal; percentiles, ranges and maxima reported for the same samples as a mean or median are shown on that row. Different forms and preparation states 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-setting medians for the same form and basis. Same-study contrasts compare a contaminated or treated site with its control, targeted with random sampling, a prepared form with the unprocessed one, or one group of a study with the median of its other groups. Held rows failed a check against their own source and are shown but not compared.

Filter findings

AnalyteFood formCollection regionCollection periodSourceCompare withComparable findings only

191 of 191 findings · 20 analytes

About this table

Food formCollection scopeFindingComparisonEvidence

Catfish findings from monitoring programmes, total diet studies and every extracted field, market and contaminated-site study, in µg/kg with each source’s form, basis, statistic and censoring retained.
Food form	Collection scope	Finding (µg/kg)

31 findings · 8 studies
Catfish, as soldWHO GEMS/Food	EURO1996–2005As sold / fresh	median.
Catfish, as soldWHO GEMS/Food	PAHO2016–2017As sold / fresh	median.
Catfish, as soldWHO GEMS/Food	PAHO2014–2017As sold / fresh	median.
Catfish, as soldWHO GEMS/Food	PAHO2017As sold / fresh	median.
Catfish, as soldWHO GEMS/Food	SEARO2014As sold / fresh	median.
Catfish, as soldWHO GEMS/Food	SEARO2009–2016As sold / fresh	median.
Catfish, as soldWHO GEMS/Food	SEARO2013As sold / fresh	median.
Catfish, as soldIslam et al. 2015	Pangas2012As sold / fresh	range.
Catfish, as soldSimionov et al. 2023	all samples (n=10), Aquaculture, VietnamCollection date unreportedAs sold / fresh	mean.
Catfish, as soldSimionov et al. 2023	all samples (n=10), Wild, Danube Delta, RomaniaCollection date unreportedAs sold / fresh	mean.
Catfish, as soldSirisangarunroj et al. 2023	freshwater fish, 3 Bangkok marketsCollection date unreportedAs sold / fresh	not detected.
Catfish, as soldauthors 2015	all three zones combined, Nov 2011 to Sep 20132011–2013Dry weight	mean.
Catfish, as soldauthors 2015	dry season (Nov-Apr), all zones2011–2013Dry weight	mean.
Catfish, as soldauthors 2015	lower zone, Ojo landing site (Badagry Creek, Nigeria)2011–2013Dry weight	mean.
Catfish, as soldauthors 2015	middle zone, Ajido landing site (Badagry Creek, Nigeria)2011–2013Dry weight	mean.
Catfish, as soldauthors 2015	upper zone, Badagry landing site (Badagry Creek, Nigeria)2011–2013Dry weight	mean.
Catfish, as soldauthors 2015	wet season (May-Oct), all zones2011–2013Dry weight	mean.
Catfish, as soldauthors 2021	Catfish (species)Collection date unreportedDry weight	mean.
Catfish, as soldSawe et al. 2023	all five landing sites2022Dry weight	mean.
Catfish, as soldSawe et al. 2023	Jangwani ziwani, African catfish (n=10)2022Dry weight	range.
Catfish, as soldSawe et al. 2023	landing site Jangwani ziwani2022Dry weight	mean.
Catfish, as soldSawe et al. 2023	landing site Mfulo wa Ng'ombe2022Dry weight	mean.
Catfish, as soldSawe et al. 2023	landing site Migunga mitatu2022Dry weight	mean.
Catfish, as soldSawe et al. 2023	landing site Minjingu2022Dry weight	mean.
Catfish, as soldSawe et al. 2023	landing site Oltukai2022Dry weight	mean.
Catfish, as soldSawe et al. 2023	Mfulo wa Ng'ombe, African catfish (n=10)2022Dry weight	range.
Catfish, as soldSawe et al. 2023	Migunga mitatu, African catfish (n=10)2022Dry weight	range.
Catfish, as soldSawe et al. 2023	Minjingu, African catfish (n=10)2022Dry weight	range.
Catfish, as soldSawe et al. 2023	Oltukai, African catfish (n=10)2022Dry weight	range.
Catfish, as soldauthors 2015	All samples2011–2013Basis not stated	range.
Catfish, as soldOnyenweaku 2025	sellers at Beach market, Calabar (3 sellers)Collection date unreportedBasis not stated	mean.
2 findings · 2 studies
Catfish, oilFDA Total Diet Study	6 collection regions2017–2020As sold / fresh	median.
Catfish, oilSpungen et al. 2024	all samples2018–2020As sold / fresh	not detected.
1 finding · 1 study
Catfish, cookedOnyenweaku 2025	roadside sellers, Calabar (3 locations)Collection date unreportedBasis not stated	not detected.

14 findings · 6 studies
Catfish, as soldWHO GEMS/Food	EURO2001–2007As sold / fresh	median.
Catfish, as soldWHO GEMS/Food	PAHO2011–2017As sold / fresh	median.
Catfish, as soldWHO GEMS/Food	PAHO2016As sold / fresh	median.
Catfish, as soldIslam et al. 2015	Pangas2012As sold / fresh	range.
Catfish, as soldSimionov et al. 2023	all samples (n=10), Aquaculture, VietnamCollection date unreportedAs sold / fresh	mean.
Catfish, as soldSimionov et al. 2023	all samples (n=10), Wild, Danube Delta, RomaniaCollection date unreportedAs sold / fresh	mean.
Catfish, as soldSirisangarunroj et al. 2023	freshwater fish, 3 Bangkok marketsCollection date unreportedAs sold / fresh	not detected.
Catfish, as soldauthors 2015	all three zones combined, Nov 2011 to Sep 20132011–2013Dry weight	not detected.
Catfish, as soldauthors 2015	dry season, all zones2011–2013Dry weight	not detected.
Catfish, as soldauthors 2015	lower zone, Ojo landing site (Badagry Creek, Nigeria)2011–2013Dry weight	not detected.
Catfish, as soldauthors 2015	middle zone, Ajido landing site (Badagry Creek, Nigeria)2011–2013Dry weight	not detected.
Catfish, as soldauthors 2015	upper zone, Badagry landing site (Badagry Creek, Nigeria)2011–2013Dry weight	not detected.
Catfish, as soldauthors 2015	wet season, all zones2011–2013Dry weight	not detected.
Catfish, as soldauthors 2021	Catfish (species)Collection date unreportedDry weight	mean.
2 findings · 2 studies
Catfish, oilFDA Total Diet Study	6 collection regions2017–2020As sold / fresh	median.
Catfish, oilSpungen et al. 2024	all samples2018–2020As sold / fresh	mean.

29 findings · 6 studies
Catfish, as soldWHO GEMS/Food	EURO2001–2005As sold / fresh	median.
Catfish, as soldWHO GEMS/Food	EURO2016–2022As sold / fresh	median.
Catfish, as soldWHO GEMS/Food	EURO2020As sold / fresh	median.
Catfish, as soldWHO GEMS/Food	PAHO2021–2022As sold / fresh	median.
Catfish, as soldIslam et al. 2015	Pangas2012As sold / fresh	range.
Catfish, as soldSimionov et al. 2023	all samples (n=10), Aquaculture, VietnamCollection date unreportedAs sold / fresh	mean.
Catfish, as soldSimionov et al. 2023	all samples (n=10), Wild, Danube Delta, RomaniaCollection date unreportedAs sold / fresh	mean.
Catfish, as soldSirisangarunroj et al. 2023	freshwater fish, 3 Bangkok marketsCollection date unreportedAs sold / fresh	mean.
Catfish, as soldauthors 2022	Cat fish, Jamuna (Joypurhat-Sadar)Collection date unreportedBasis not stated	range.
Catfish, as soldauthors 2022	Cat fish, Jamuna (Pachbibi)Collection date unreportedBasis not stated	range.
Catfish, as soldauthors 2022	Cat fish, Nandail (Kalai)Collection date unreportedBasis not stated	range.
Catfish, as soldauthors 2022	Cat fish, Tulshiganga (Akkelpur)Collection date unreportedBasis not stated	range.
Catfish, as soldauthors 2022	Cat fish, Tulshiganga (Khetlal)Collection date unreportedBasis not stated	range.
Catfish, as soldauthors 2022	Jamuna (Joypurhat-Sadar) river fishCollection date unreportedBasis not stated	mean.
Catfish, as soldauthors 2022	Jamuna (Pachbibi) river fishCollection date unreportedBasis not stated	mean.
Catfish, as soldauthors 2022	Nandail (Kalai) river fishCollection date unreportedBasis not stated	mean.
Catfish, as soldauthors 2022	Tulshiganga (Akkelpur) river fishCollection date unreportedBasis not stated	mean.
Catfish, as soldauthors 2022	Tulshiganga (Khetlal) river fishCollection date unreportedBasis not stated	mean.
Catfish, as soldauthors 2022	Tyangra fish, Jamuna (Joypurhat-Sadar)Collection date unreportedBasis not stated	range.
Catfish, as soldauthors 2022	Tyangra fish, Jamuna (Pachbibi)Collection date unreportedBasis not stated	range.
Catfish, as soldauthors 2022	Tyangra fish, Nandail (Kalai)Collection date unreportedBasis not stated	range.
Catfish, as soldauthors 2022	Tyangra fish, Tulshiganga (Akkelpur)Collection date unreportedBasis not stated	range.
Catfish, as soldauthors 2022	Tyangra fish, Tulshiganga (Khetlal)Collection date unreportedBasis not stated	range.
Catfish, as soldPaul et al. 2025	Mv Lower part (Noakhali, N8–N10)2022–2023Basis not stated	range.
Catfish, as soldPaul et al. 2025	Mv Mid part (Lakshmipur, L4–L7)2022–2023Basis not stated	range.
Catfish, as soldPaul et al. 2025	Mv Monsoon (June)2022–2023Basis not stated	range.
Catfish, as soldPaul et al. 2025	Mv Post-monsoon (October)2022–2023Basis not stated	range.
Catfish, as soldPaul et al. 2025	Mv Pre-monsoon (March)2022–2023Basis not stated	range.
Catfish, as soldPaul et al. 2025	Mv Upper part (Chandpur, C1–C3)2022–2023Basis not stated	range.
1 finding · 1 study
Catfish, oilFDA Total Diet Study	6 collection regions2017–2020As sold / fresh	median.

2 findings · 1 study
Catfish, as soldWHO GEMS/Food	EURO2019As sold / fresh	median.
Catfish, as soldWHO GEMS/Food	WPRO2022As sold / fresh	median.

26 findings · 13 studies · 10 spread figures folded in
Catfish, as soldWHO GEMS/Food	EURO2005As sold / fresh	median.
Catfish, as soldWHO GEMS/Food	PAHO2019As sold / fresh	median.
Catfish, as soldWHO GEMS/Food	PAHO2017–2018As sold / fresh	median.
Catfish, as soldWHO GEMS/Food	PAHO2016As sold / fresh	median.
Catfish, as soldAliya et al. 2018	traditional dry fish processing plants, OmanCollection date unreportedAs sold / fresh	mean.
Catfish, as soldBezerra 2026	Hoplosternum littorale (Fl)2013–2023As sold / fresh	range.
Catfish, as soldBezerra 2026	Hypostomus pusarum (Fl)2013–2023As sold / fresh	range.
Catfish, as soldHealey 2021	Anacostia River Blue Catfish FP2017–2018As sold / fresh	range.
Catfish, as soldHealey 2021	Anacostia River Blue Catfish HF2017–2018As sold / fresh	range.
Catfish, as soldHealey 2021	Anacostia River, fillet plug (FP, two 8-mm biopsy punches)2017–2018As sold / fresh	median.
Catfish, as soldHealey 2021	Anacostia River, fillet plug (FP, two 8-mm biopsy punches)2017–2018As sold / fresh	mean.Same samples: 44.2 µg/kg (minimum); 308 µg/kg (maximum)
Catfish, as soldHealey 2021	Anacostia River, fillet plug (FP, two 8-mm biopsy punches)2017–2018As sold / fresh	min.
Catfish, as soldHealey 2021	Anacostia River, fillet plug (FP, two 8-mm biopsy punches)2017–2018As sold / fresh	max.
Catfish, as soldHealey 2021	Anacostia River, homogenized fillet (HF)2017–2018As sold / fresh	median.
Catfish, as soldHealey 2021	Anacostia River, homogenized fillet (HF)2017–2018As sold / fresh	mean.Same samples: 23 µg/kg (minimum); 284 µg/kg (maximum)
Catfish, as soldHealey 2021	Anacostia River, homogenized fillet (HF)2017–2018As sold / fresh	min.
Catfish, as soldHealey 2021	Anacostia River, homogenized fillet (HF)2017–2018As sold / fresh	max.
Catfish, as soldSimionov et al. 2023	all samples (n=10), Aquaculture, VietnamCollection date unreportedAs sold / fresh	mean.
Catfish, as soldSimionov et al. 2023	all samples (n=10), Wild, Danube Delta, RomaniaCollection date unreportedAs sold / fresh	mean.
Catfish, as soldSirisangarunroj et al. 2023	freshwater fish, 3 Bangkok marketsCollection date unreportedAs sold / fresh	not detected.
Catfish, as soldauthors 2021	Catfish (species)Collection date unreportedDry weight	mean.
Catfish, as soldMoura et al. 2022	fluvial-dominated estuary end2015–2019Dry weight	mean.
Catfish, as soldMoura et al. 2022	marine-dominated estuary end2015–2019Dry weight	mean.
Catfish, as soldBrodziak-Dopierala et al. 2023	all samples of species2021–2022Basis not stated	mean.
Catfish, as soldEFSA Panel on Contaminants in the Food Chain (CONTAM) 2012	EU occurrence data2004–2011Basis not stated	median.
Catfish, as soldEFSA Panel on Contaminants in the Food Chain (CONTAM) 2012	EU occurrence data2004–2011Basis not stated	mean.Same samples: 950 µg/kg (maximum); 770 µg/kg (percentile); 850 µg/kg (percentile); 950 µg/kg (percentile)
Catfish, as soldEFSA Panel on Contaminants in the Food Chain (CONTAM) 2012	EU occurrence data2004–2011Basis not stated	max.
Catfish, as soldEFSA Panel on Contaminants in the Food Chain (CONTAM) 2012	EU occurrence data2004–2011Basis not stated	percentile.
Catfish, as soldEFSA Panel on Contaminants in the Food Chain (CONTAM) 2012	EU occurrence data2004–2011Basis not stated	percentile.
Catfish, as soldEFSA Panel on Contaminants in the Food Chain (CONTAM) 2012	EU occurrence data2004–2011Basis not stated	percentile.
Catfish, as soldGerman Federal Institute for Risk Assessment (BfR) 2024	German food monitoring 2012-2021 (BVL 2017)2012–2021Basis not stated	mean.Same samples: 80 µg/kg (maximum); 10 µg/kg (percentile)
Catfish, as soldGerman Federal Institute for Risk Assessment (BfR) 2024	German food monitoring 2012-2021 (BVL 2017)2012–2021Basis not stated	max.
Catfish, as soldGerman Federal Institute for Risk Assessment (BfR) 2024	German food monitoring 2012-2021 (BVL 2017)2012–2021Basis not stated	percentile.
Catfish, as soldGerman Federal Institute for Risk Assessment (BfR) 2024	national pool2012–2021Basis not stated	not detected.
Catfish, as soldLin et al. 2021	Inshore Fish: CatfishCollection date unreportedBasis not stated	not detected.
Catfish, as soldOnyenweaku 2025	sellers at Beach market, Calabar (3 sellers)Collection date unreportedBasis not stated	not detected.
1 finding · 1 study
Catfish, oilFDA Total Diet Study	6 collection regions2017–2020As sold / fresh	median.
1 finding · 1 study
Catfish, cookedOnyenweaku 2025	roadside sellers, Calabar (3 locations)Collection date unreportedBasis not stated	not detected.

3 findings · 2 studies · 1 spread figure folded in
Catfish, as soldEFSA Panel on Contaminants in the Food Chain (CONTAM) 2012	EU occurrence data2004–2011Basis not stated	median.
Catfish, as soldEFSA Panel on Contaminants in the Food Chain (CONTAM) 2012	EU occurrence data2004–2011Basis not stated	mean.Same samples: 121 µg/kg (maximum)
Catfish, as soldEFSA Panel on Contaminants in the Food Chain (CONTAM) 2012	EU occurrence data2004–2011Basis not stated	max.
Catfish, as soldGerman Federal Institute for Risk Assessment (BfR) 2024	national pool2012–2021Basis not stated	not detected.

14 findings · 3 studies
Catfish, as soldIslam et al. 2015	Pangas2012As sold / fresh	range.
Catfish, as soldSimionov et al. 2023	all samples (n=10), Aquaculture, VietnamCollection date unreportedAs sold / fresh	mean.
Catfish, as soldSimionov et al. 2023	all samples (n=10), Wild, Danube Delta, RomaniaCollection date unreportedAs sold / fresh	mean.
Catfish, as soldSawe et al. 2023	all five landing sites2022Dry weight	mean.
Catfish, as soldSawe et al. 2023	Jangwani ziwani, African catfish (n=10)2022Dry weight	range.
Catfish, as soldSawe et al. 2023	landing site Jangwani ziwani2022Dry weight	mean.
Catfish, as soldSawe et al. 2023	landing site Mfulo wa Ng'ombe2022Dry weight	mean.
Catfish, as soldSawe et al. 2023	landing site Migunga mitatu2022Dry weight	mean.
Catfish, as soldSawe et al. 2023	landing site Minjingu2022Dry weight	mean.
Catfish, as soldSawe et al. 2023	landing site Oltukai2022Dry weight	mean.
Catfish, as soldSawe et al. 2023	Mfulo wa Ng'ombe, African catfish (n=10)2022Dry weight	range.
Catfish, as soldSawe et al. 2023	Migunga mitatu, African catfish (n=10)2022Dry weight	range.
Catfish, as soldSawe et al. 2023	Minjingu, African catfish (n=10)2022Dry weight	range.
Catfish, as soldSawe et al. 2023	Oltukai, African catfish (n=10)2022Dry weight	range.
1 finding · 1 study
Catfish, oilFDA Total Diet Study	6 collection regions2017–2020As sold / fresh	median.

10 findings · 3 studies
Catfish, as soldIslam et al. 2015	Pangas2012As sold / fresh	range.
Catfish, as soldSimionov et al. 2023	all samples (n=10), Aquaculture, VietnamCollection date unreportedAs sold / fresh	mean.
Catfish, as soldSimionov et al. 2023	all samples (n=10), Wild, Danube Delta, RomaniaCollection date unreportedAs sold / fresh	mean.
Catfish, as soldauthors 2015	all three zones combined, Nov 2011 to Sep 20132011–2013Dry weight	mean.
Catfish, as soldauthors 2015	dry season (Nov-Apr), all zones2011–2013Dry weight	mean.
Catfish, as soldauthors 2015	lower zone, Ojo landing site (Badagry Creek, Nigeria)2011–2013Dry weight	mean.
Catfish, as soldauthors 2015	middle zone, Ajido landing site (Badagry Creek, Nigeria)2011–2013Dry weight	mean.
Catfish, as soldauthors 2015	upper zone, Badagry landing site (Badagry Creek, Nigeria)2011–2013Dry weight	mean.
Catfish, as soldauthors 2015	wet season (May-Oct), all zones2011–2013Dry weight	mean.
Catfish, as soldauthors 2015	All samples2011–2013Basis not stated	range.
1 finding · 1 study
Catfish, oilFDA Total Diet Study	6 collection regions2017–2020As sold / fresh	median.

2 findings · 1 study
Catfish, as soldSimionov et al. 2023	all samples (n=10), Aquaculture, VietnamCollection date unreportedAs sold / fresh	mean.
Catfish, as soldSimionov et al. 2023	all samples (n=10), Wild, Danube Delta, RomaniaCollection date unreportedAs sold / fresh	mean.
1 finding · 1 study
Catfish, cookedOnyenweaku 2025	roadside sellers, Calabar (3 locations)Collection date unreportedBasis not stated	mean.

1 finding · 1 study
Catfish, oilFDA Total Diet Study	6 collection regions2017–2020As sold / fresh	median.

14 findings · 3 studies
Catfish, as soldSimionov et al. 2023	all samples (n=10), Aquaculture, VietnamCollection date unreportedAs sold / fresh	mean.
Catfish, as soldSimionov et al. 2023	all samples (n=10), Wild, Danube Delta, RomaniaCollection date unreportedAs sold / fresh	mean.
Catfish, as soldauthors 2015	all three zones combined, Nov 2011 to Sep 20132011–2013Dry weight	mean.
Catfish, as soldauthors 2015	dry season (Nov-Apr), all zones2011–2013Dry weight	mean.
Catfish, as soldauthors 2015	lower zone, Ojo landing site (Badagry Creek, Nigeria)2011–2013Dry weight	mean.
Catfish, as soldauthors 2015	middle zone, Ajido landing site (Badagry Creek, Nigeria)2011–2013Dry weight	mean.
Catfish, as soldauthors 2015	upper zone, Badagry landing site (Badagry Creek, Nigeria)2011–2013Dry weight	mean.
Catfish, as soldauthors 2015	wet season (May-Oct), all zones2011–2013Dry weight	mean.
Catfish, as soldSawe et al. 2023	all five landing sites2022Dry weight	mean.
Catfish, as soldSawe et al. 2023	landing site Jangwani ziwani2022Dry weight	mean.
Catfish, as soldSawe et al. 2023	landing site Mfulo wa Ng'ombe2022Dry weight	mean.
Catfish, as soldSawe et al. 2023	landing site Migunga mitatu2022Dry weight	mean.
Catfish, as soldSawe et al. 2023	landing site Minjingu2022Dry weight	mean.
Catfish, as soldSawe et al. 2023	landing site Oltukai2022Dry weight	mean.

6 findings · 1 study
Catfish, as soldauthors 2015	all three zones combined, Nov 2011 to Sep 20132011–2013Dry weight	mean.
Catfish, as soldauthors 2015	dry season (Nov-Apr), all zones2011–2013Dry weight	mean.
Catfish, as soldauthors 2015	lower zone, Ojo landing site (Badagry Creek, Nigeria)2011–2013Dry weight	mean.
Catfish, as soldauthors 2015	middle zone, Ajido landing site (Badagry Creek, Nigeria)2011–2013Dry weight	mean.
Catfish, as soldauthors 2015	upper zone, Badagry landing site (Badagry Creek, Nigeria)2011–2013Dry weight	mean.
Catfish, as soldauthors 2015	wet season (May-Oct), all zones2011–2013Dry weight	mean.

14 findings · 3 studies
Catfish, as soldSimionov et al. 2023	all samples (n=10), Aquaculture, VietnamCollection date unreportedAs sold / fresh	mean.
Catfish, as soldSimionov et al. 2023	all samples (n=10), Wild, Danube Delta, RomaniaCollection date unreportedAs sold / fresh	mean.
Catfish, as soldauthors 2015	all three zones combined, Nov 2011 to Sep 20132011–2013Dry weight	mean.
Catfish, as soldauthors 2015	dry season (Nov-Apr), all zones2011–2013Dry weight	mean.
Catfish, as soldauthors 2015	lower zone, Ojo landing site (Badagry Creek, Nigeria)2011–2013Dry weight	mean.
Catfish, as soldauthors 2015	middle zone, Ajido landing site (Badagry Creek, Nigeria)2011–2013Dry weight	mean.
Catfish, as soldauthors 2015	upper zone, Badagry landing site (Badagry Creek, Nigeria)2011–2013Dry weight	mean.
Catfish, as soldauthors 2015	wet season (May-Oct), all zones2011–2013Dry weight	mean.
Catfish, as soldSawe et al. 2023	all five landing sites2022Dry weight	mean.
Catfish, as soldSawe et al. 2023	landing site Jangwani ziwani2022Dry weight	mean.
Catfish, as soldSawe et al. 2023	landing site Mfulo wa Ng'ombe2022Dry weight	mean.
Catfish, as soldSawe et al. 2023	landing site Migunga mitatu2022Dry weight	mean.
Catfish, as soldSawe et al. 2023	landing site Minjingu2022Dry weight	mean.
Catfish, as soldSawe et al. 2023	landing site Oltukai2022Dry weight	mean.

8 findings · 1 study · 8 spread figures folded in
Catfish, as soldHealey 2021	Anacostia River, fillet plug (FP, two 8-mm biopsy punches)2017–2018As sold / fresh	median.
Catfish, as soldHealey 2021	Anacostia River, fillet plug (FP, two 8-mm biopsy punches)2017–2018As sold / fresh	mean.Same samples: 139 µg/kg (minimum); 234 µg/kg (maximum); 711 µg/kg (minimum); 1,160 µg/kg (maximum)
Catfish, as soldHealey 2021	Anacostia River, fillet plug (FP, two 8-mm biopsy punches)2017–2018As sold / fresh	min.
Catfish, as soldHealey 2021	Anacostia River, fillet plug (FP, two 8-mm biopsy punches)2017–2018As sold / fresh	max.
Catfish, as soldHealey 2021	Anacostia River, homogenized fillet (HF)2017–2018As sold / fresh	median.
Catfish, as soldHealey 2021	Anacostia River, homogenized fillet (HF)2017–2018As sold / fresh	mean.Same samples: 145 µg/kg (minimum); 182 µg/kg (maximum); 750 µg/kg (minimum); 925 µg/kg (maximum)
Catfish, as soldHealey 2021	Anacostia River, homogenized fillet (HF)2017–2018As sold / fresh	min.
Catfish, as soldHealey 2021	Anacostia River, homogenized fillet (HF)2017–2018As sold / fresh	max.
Catfish, as soldHealey 2021	Anacostia River, fillet plug (FP, two 8-mm biopsy punches)2017–2018Dry weight	median.
Catfish, as soldHealey 2021	Anacostia River, fillet plug (FP, two 8-mm biopsy punches)2017–2018Dry weight	mean.
Catfish, as soldHealey 2021	Anacostia River, fillet plug (FP, two 8-mm biopsy punches)2017–2018Dry weight	min.
Catfish, as soldHealey 2021	Anacostia River, fillet plug (FP, two 8-mm biopsy punches)2017–2018Dry weight	max.
Catfish, as soldHealey 2021	Anacostia River, homogenized fillet (HF)2017–2018Dry weight	median.
Catfish, as soldHealey 2021	Anacostia River, homogenized fillet (HF)2017–2018Dry weight	mean.
Catfish, as soldHealey 2021	Anacostia River, homogenized fillet (HF)2017–2018Dry weight	min.
Catfish, as soldHealey 2021	Anacostia River, homogenized fillet (HF)2017–2018Dry weight	max.

1 finding · 1 study
Catfish, as soldJianying et al. 2006	Bohai Bay, muscle2002As sold / fresh	mean.

1 finding · 1 study
Catfish, as soldJianying et al. 2006	Bohai Bay, muscle2002As sold / fresh	not detected.

1 finding · 1 study
Catfish, as soldJianying et al. 2006	Bohai Bay, muscle2002As sold / fresh	mean.

1 finding · 1 study
Catfish, as soldJianying et al. 2006	Bohai Bay, muscle2002As sold / fresh	not detected.

1 finding · 1 study
Catfish, as soldJianying et al. 2006	Bohai Bay, muscle2002As sold / fresh	mean.

1 finding · 1 study
Catfish, as soldJianying et al. 2006	Bohai Bay, muscle2002As sold / fresh	mean.

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 catfish Pb reference · Catfish, as sold

Reference and scope

HMI catfish Pb reference · Catfish, as sold. Catfish, as sold; 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	≤10	≤12.3	≤12.3
Alternative weighting	≤10	≤12.3	≤12.3

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

Contributing family	Reference units	Weight
WHO GEMS/Food	21	50%
Sirisangarunroj et al. 2023	1	50%

Methods

HMI pools subgroup medians for catfish, as sold on a as sold, as eaten or fresh weight basis: monitoring results summarized as one median per reporting region, sampling type and collection year, total diet composites and printed sample values as single observations, and printed subgroup medians from ordinary farms or markets. 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, other bases, targeted sampling and results from mining, industrial, wastewater-affected, experimental, fertiliser or manufacturer settings 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. Reporting regions and purchase markets are not growing areas. Non-detects with differing limits widen 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:catfish-84601c032595:9b39afd7f2a8

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 catfish Pb reference · Catfish, oil

Reference and scope

HMI catfish Pb reference · Catfish, oil. Catfish, oil; 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	≤4
Alternative weighting	≤4	≤4	≤4

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

Contributing family	Reference units	Weight
FDA Total Diet Study	27	50%
Spungen et al. 2024	1	50%

Methods

HMI pools subgroup medians for catfish, oil on a as sold, as eaten or fresh weight basis: monitoring results summarized as one median per reporting region, sampling type and collection year, total diet composites and printed sample values as single observations, and printed subgroup medians from ordinary farms or markets. 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, other bases, targeted sampling and results from mining, industrial, wastewater-affected, experimental, fertiliser or manufacturer settings 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. Reporting regions and purchase markets are not growing areas. Non-detects with differing limits widen 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:catfish-17b4bac2639a:d6e3c43e4696

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 catfish Cd reference · Catfish, as sold

Reference and scope

HMI catfish Cd reference · Catfish, as sold. Catfish, as sold; 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	≤0.9	≤0.95	≤6.87
Alternative weighting	≤0.9	≤0.95	≤6.87

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

Contributing family	Reference units	Weight
WHO GEMS/Food	11	50%
Sirisangarunroj et al. 2023	1	50%

Methods

HMI pools subgroup medians for catfish, as sold on a as sold, as eaten or fresh weight basis: monitoring results summarized as one median per reporting region, sampling type and collection year, total diet composites and printed sample values as single observations, and printed subgroup medians from ordinary farms or markets. 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, other bases, targeted sampling and results from mining, industrial, wastewater-affected, experimental, fertiliser or manufacturer settings 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. Reporting regions and purchase markets are not growing areas. Non-detects with differing limits widen 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:catfish-d90c6f410b6f:a0881b4133d1

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 catfish Cd reference · Catfish, oil

Reference and scope

HMI catfish Cd reference · Catfish, oil. Catfish, oil; 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 catfish, oil on a as sold, as eaten or fresh weight basis: monitoring results summarized as one median per reporting region, sampling type and collection year, total diet composites and printed sample values as single observations, and printed subgroup medians from ordinary farms or markets. 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, other bases, targeted sampling and results from mining, industrial, wastewater-affected, experimental, fertiliser or manufacturer settings 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 catfish, oil on this basis in the completed catfish ledger, so this single-family reference cannot represent other markets. Reporting regions and purchase markets are not growing areas. Non-detects with differing limits widen 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:catfish-0abaf0d4b1b6:37a04e4efe71

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 catfish tAs reference · Catfish, as sold

Reference and scope

HMI catfish tAs reference · Catfish, as sold. Catfish, as sold; 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	17.9–91 (bounded)	91–100 (bounded)
Alternative weighting	≤30	17.9–91 (bounded)	91–100 (bounded)

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

Contributing family	Reference units	Weight
WHO GEMS/Food	9	100%

Methods

HMI pools subgroup medians for catfish, as sold on a as sold, as eaten or fresh weight basis: monitoring results summarized as one median per reporting region, sampling type and collection year, total diet composites and printed sample values as single observations, and printed subgroup medians from ordinary farms or markets. 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, other bases, targeted sampling and results from mining, industrial, wastewater-affected, experimental, fertiliser or manufacturer settings 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

WHO GEMS/Food is the only compatible sampling family for catfish, as sold on this basis in the completed catfish ledger, so this single-family reference cannot represent other markets. Reporting regions and purchase markets are not growing areas. Non-detects with differing limits widen 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:catfish-c7b2c25148c2:6f53a5d9d0f9

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 catfish tAs reference · Catfish, oil

Reference and scope

HMI catfish tAs reference · Catfish, oil. Catfish, oil; 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	11	24	32
Alternative weighting	11	24.5	32

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 catfish, oil on a as sold, as eaten or fresh weight basis: monitoring results summarized as one median per reporting region, sampling type and collection year, total diet composites and printed sample values as single observations, and printed subgroup medians from ordinary farms or markets. 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, other bases, targeted sampling and results from mining, industrial, wastewater-affected, experimental, fertiliser or manufacturer settings 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 catfish, oil on this basis in the completed catfish ledger, so this single-family reference cannot represent other markets. Reporting regions and purchase markets are not growing areas. Non-detects with differing limits widen 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:catfish-fcf149dff1e6:8963e6ce7da5

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 catfish iAs reference · Catfish, as sold

Reference and scope

HMI catfish iAs reference · Catfish, as sold. Catfish, as sold; 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	≤6.1	≤13.1	≤20
Alternative weighting	≤6.1	≤13.1	≤20

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 catfish, as sold on a as sold, as eaten or fresh weight basis: monitoring results summarized as one median per reporting region, sampling type and collection year, total diet composites and printed sample values as single observations, and printed subgroup medians from ordinary farms or markets. 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, other bases, targeted sampling and results from mining, industrial, wastewater-affected, experimental, fertiliser or manufacturer settings 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

WHO GEMS/Food is the only compatible sampling family for catfish, as sold on this basis in the completed catfish ledger, so this single-family reference cannot represent other markets. Reporting regions and purchase markets are not growing areas. Non-detects with differing limits widen 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:catfish-e3d7a24a6e97:583c1df196a1

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 catfish tHg reference · Catfish, as sold

Reference and scope

HMI catfish tHg reference · Catfish, as sold. Catfish, as sold; 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	≤11.2	5–12.4 (bounded)	86.5
Alternative weighting	≤11.2	5–12.4 (bounded)	86.5

7 reference units; 3 sampling families. Counts describe evidence units, not independent studies or certainty.

Contributing family	Reference units	Weight
WHO GEMS/Food	4	33%
Healey 2021	2	33%
Sirisangarunroj et al. 2023	1	33%

Methods

HMI pools subgroup medians for catfish, as sold on a as sold, as eaten or fresh weight basis: monitoring results summarized as one median per reporting region, sampling type and collection year, total diet composites and printed sample values as single observations, and printed subgroup medians from ordinary farms or markets. 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, other bases, targeted sampling and results from mining, industrial, wastewater-affected, experimental, fertiliser or manufacturer settings 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

3 sampling families with different designs; none is a probability sample of world supply. Reporting regions and purchase markets are not growing areas. Non-detects with differing limits widen 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:catfish-7b70c1b9720b:ffba1dc83329

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 catfish tHg reference · Catfish, oil

Reference and scope

HMI catfish tHg reference · Catfish, oil. Catfish, oil; 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	3.6	4.3	5.2
Alternative weighting	3.6	4.6	5.2

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 catfish, oil on a as sold, as eaten or fresh weight basis: monitoring results summarized as one median per reporting region, sampling type and collection year, total diet composites and printed sample values as single observations, and printed subgroup medians from ordinary farms or markets. 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, other bases, targeted sampling and results from mining, industrial, wastewater-affected, experimental, fertiliser or manufacturer settings 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 catfish, oil on this basis in the completed catfish ledger, so this single-family reference cannot represent other markets. Reporting regions and purchase markets are not growing areas. Non-detects with differing limits widen 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:catfish-dc6c7acb1200:bc43f7a53f5a

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 catfish Ni reference · Catfish, oil

Reference and scope

HMI catfish Ni reference · Catfish, oil. Catfish, oil; 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 catfish, oil on a as sold, as eaten or fresh weight basis: monitoring results summarized as one median per reporting region, sampling type and collection year, total diet composites and printed sample values as single observations, and printed subgroup medians from ordinary farms or markets. 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, other bases, targeted sampling and results from mining, industrial, wastewater-affected, experimental, fertiliser or manufacturer settings 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 catfish, oil on this basis in the completed catfish ledger, so this single-family reference cannot represent other markets. Reporting regions and purchase markets are not growing areas. Non-detects with differing limits widen 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:catfish-6baaed3e86ce:5d13421b0cc1

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 catfish Cr reference · Catfish, oil

Reference and scope

HMI catfish Cr reference · Catfish, oil. Catfish, oil; 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 catfish, oil on a as sold, as eaten or fresh weight basis: monitoring results summarized as one median per reporting region, sampling type and collection year, total diet composites and printed sample values as single observations, and printed subgroup medians from ordinary farms or markets. 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, other bases, targeted sampling and results from mining, industrial, wastewater-affected, experimental, fertiliser or manufacturer settings 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 catfish, oil on this basis in the completed catfish ledger, so this single-family reference cannot represent other markets. Reporting regions and purchase markets are not growing areas. Non-detects with differing limits widen 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:catfish-e85343366047:bec74c521cc6

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 catfish U reference · Catfish, oil

Reference and scope

HMI catfish U reference · Catfish, oil. Catfish, oil; 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 catfish, oil on a as sold, as eaten or fresh weight basis: monitoring results summarized as one median per reporting region, sampling type and collection year, total diet composites and printed sample values as single observations, and printed subgroup medians from ordinary farms or markets. 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, other bases, targeted sampling and results from mining, industrial, wastewater-affected, experimental, fertiliser or manufacturer settings 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 catfish, oil on this basis in the completed catfish ledger, so this single-family reference cannot represent other markets. Reporting regions and purchase markets are not growing areas. Non-detects with differing limits widen 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:catfish-77cb199793b4:e8ba7f70b346

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 catfish Se reference · Catfish, as sold

Reference and scope

HMI catfish Se reference · Catfish, as sold. Catfish, as sold; 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	170	171	173
Alternative weighting	170	171	173

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

Contributing family	Reference units	Weight
Healey 2021	2	100%

Methods

HMI pools subgroup medians for catfish, as sold on a as sold, as eaten or fresh weight basis: monitoring results summarized as one median per reporting region, sampling type and collection year, total diet composites and printed sample values as single observations, and printed subgroup medians from ordinary farms or markets. 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, other bases, targeted sampling and results from mining, industrial, wastewater-affected, experimental, fertiliser or manufacturer settings 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

Healey 2021 is the only compatible sampling family for catfish, as sold on this basis in the completed catfish ledger, so this single-family reference cannot represent other markets. Reporting regions and purchase markets are not growing areas. Non-detects with differing limits widen the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

Healey 2021

Reference version and interpretation

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

hmi-pooled-reference-v2:catfish-cac90a7532cb:f0636340e819

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 catfish Se reference · Catfish, as sold, dry weight

Reference and scope

HMI catfish Se reference · Catfish, as sold, dry weight. Catfish, as sold; Dry weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.

Reference (µg/kg)	Q1	Median	Q3
Primary HMI reference	834	851	868
Alternative weighting	834	851	868

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

Contributing family	Reference units	Weight
Healey 2021	2	100%

Methods

HMI pools subgroup medians for catfish, as sold on a dry weight basis: monitoring results summarized as one median per reporting region, sampling type and collection year, total diet composites and printed sample values as single observations, and printed subgroup medians from ordinary farms or markets. 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, other bases, targeted sampling and results from mining, industrial, wastewater-affected, experimental, fertiliser or manufacturer settings 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

Healey 2021 is the only compatible sampling family for catfish, as sold on this basis in the completed catfish ledger, so this single-family reference cannot represent other markets. Reporting regions and purchase markets are not growing areas. Non-detects with differing limits widen the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

Healey 2021

Reference version and interpretation

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

hmi-pooled-reference-v2:catfish-87abb39440f3:47b68e37f093

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 catfish organotin_DPT reference · Catfish, as sold

Reference and scope

HMI catfish organotin_DPT reference · Catfish, as sold. Catfish, as sold; 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

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

Contributing family	Reference units	Weight
Jianying et al. 2006	1	100%

Methods

HMI pools subgroup medians for catfish, as sold on a as sold, as eaten or fresh weight basis: monitoring results summarized as one median per reporting region, sampling type and collection year, total diet composites and printed sample values as single observations, and printed subgroup medians from ordinary farms or markets. 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, other bases, targeted sampling and results from mining, industrial, wastewater-affected, experimental, fertiliser or manufacturer settings 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

Jianying et al. 2006 is the only compatible sampling family for catfish, as sold on this basis in the completed catfish ledger, so this single-family reference cannot represent other markets. Reporting regions and purchase markets are not growing areas. Non-detects with differing limits widen the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

Jianying et al. 2006

Reference version and interpretation

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

hmi-pooled-reference-v2:catfish-ea436e15a8a7:5a6ee3806c1a

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 catfish organotin_MPT reference · Catfish, as sold

Reference and scope

HMI catfish organotin_MPT reference · Catfish, as sold. Catfish, as sold; 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	≤2.5	≤2.5	≤2.5
Alternative weighting	≤2.5	≤2.5	≤2.5

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

Contributing family	Reference units	Weight
Jianying et al. 2006	1	100%

Methods

HMI pools subgroup medians for catfish, as sold on a as sold, as eaten or fresh weight basis: monitoring results summarized as one median per reporting region, sampling type and collection year, total diet composites and printed sample values as single observations, and printed subgroup medians from ordinary farms or markets. 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, other bases, targeted sampling and results from mining, industrial, wastewater-affected, experimental, fertiliser or manufacturer settings 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

Jianying et al. 2006 is the only compatible sampling family for catfish, as sold on this basis in the completed catfish ledger, so this single-family reference cannot represent other markets. Reporting regions and purchase markets are not growing areas. Non-detects with differing limits widen the bounds. A position is descriptive concentration, not a safety or compliance judgment.

Admitted source families

Jianying et al. 2006

Reference version and interpretation

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

hmi-pooled-reference-v2:catfish-143492f9b8d3:fc80054e8dd3

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 catfish

No study in the library compared catfish from contaminated and ordinary settings, so the routes by which metals reach it are not measured here.

Which forms and regions measured lower

The HMI reference for lead in catfish, oil pools 28 subgroup units from 2 sampling families, with a median of below 4 µg/kg and a middle half spanning below 4 (lower quartile) and below 4 µg/kg (upper quartile).^{2U.S. Food and Drug Administration · 2022FY2018-FY2020 TDS Elements Analytical ResultsFDA Total Diet StudyRead source →}^{8Spungen JH, et al. · 2024Infants’ and young children’s dietary exposures to lead and cadmium: FDA total diet study 2018-2020Food Additives & Contaminants: Part ARead source →} For lead in catfish, as sold, the reference median was below 12.3 µg/kg, with a middle half from below 10 to below 12.3 µg/kg across 22 units.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}^{5Sirisangarunroj P, Monboonpitak N, Karnpanit W, Sridonpai P, Singhato A, Laitip N, Ornthai N, Yafa C, Judprasong K · 2023Toxic Heavy Metals and Their Risk Assessment of Exposure in Selected Freshwater and Marine Fish in ThailandFoods 2023, 12, 3967Read source →} For cadmium in catfish, as sold, the reference median was below 0.95 µg/kg, with a middle half from below 0.9 to below 6.87 µg/kg across 12 units.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}^{5Sirisangarunroj P, Monboonpitak N, Karnpanit W, Sridonpai P, Singhato A, Laitip N, Ornthai N, Yafa C, Judprasong K · 2023Toxic Heavy Metals and Their Risk Assessment of Exposure in Selected Freshwater and Marine Fish in ThailandFoods 2023, 12, 3967Read source →}

Targeted catfish, as sold samples in PAHO had total mercury lower at 7.1 µg/kg, against 10 µg/kg for PAHO in the same study.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}

In one study, total arsenic across 5 groups of catfish ranged from 42 µg/kg (Nandail (Kalai) river fish) to 524 µg/kg (Tulshiganga (Akkelpur) river fish); the lowest is the lowest observed in that study, not an established sourcing preference.^{10Unknown authors · 2022Arsenic Contamination in Soil, Vegetable, Groundwater, and Riverine FishPeer-reviewed articleRead source →} In another study, nickel across 4 groups of catfish ranged from 750 µg/kg (landing site Jangwani ziwani) to 800 µg/kg (landing site Mfulo wa Ng’ombe); the lowest is the lowest observed in that study, not an established sourcing preference.^{9Sawe S, Amasi A, Wynants M · 2023Assessment of Potentially Toxic Metals in Fish from Lake Manyara, Northern TanzaniaBulletin of Environmental Contamination and ToxicologyRead source →}

Processing, cooking and preparation

No study in the library measured the same catfish before and after washing, peeling, drying or cooking for metals, so no processing effect can be stated. Heat does not destroy metals; cooking or drying changes a concentration by moving water or metal, not by removing the element.

Mitigation for catfish

Controls with evidence for catfish act at the stages below. Select smaller fish within a species (evidence from fish): modelled mean mercury in pike under 600 mm was about two to three times lower than in pike of 600 mm or longer.^{11Jermilova U, Kirk JL, Moe SJ, Landis WG, Sharpe E, McGovern M, Braaten HFV, Gundersen CB, Dastoor AP, Schaefer K, Hintelmann HH · 2025Assessing mercury exposure to water and fish of the Mackenzie watershed using a Bayesian network analysisIntegrated Environmental Assessment and ManagementRead source →} Use resin-coated cans for fish (evidence from fish): tuna in resin-coated cans had 700 µg/kg tin against up to 73,680 µg/kg in acidic tomato products in uncoated cans.^{12Trandafir I, Nour V, Ionica ME · 2012Determination of Tin in Canned Foods by Inductively Coupled Plasma-Mass SpectrometryPolish Journal of Environmental StudiesRead source →} Lot sampling for methylmercury with total mercury screening (evidence from fish): lots are grouped by one species and comparable size; a total mercury result at or below the methylmercury limit is compliant, otherwise methylmercury is measured.^{13Codex Alimentarius Commission, Codex Committee on Contaminants in Foods · 2024Report of the 17th Session of the Codex Committee on Contaminants in Foods (REP24/CF17)Joint FAO/WHO Food Standards Programme, Codex Alimentarius CommissionRead source →}

Choose lower-mercury species (evidence from fish): two to three servings a week from Best Choices such as salmon, sardines, cod and tilapia; avoid shark, swordfish, king mackerel, marlin, orange roughy, Gulf tilefish and bigeye tuna.^{14U.S. Food and Drug Administration, U.S. Environmental Protection Agency · 2017Advice About Eating Fish — For Those Who Might Become or Are Pregnant or Breastfeeding and Children Ages 1 to 11 YearsU.S. FDA and U.S. EPARead source →} Prefer younger fish of the same species (evidence from fish): young yellowtail (inada) averaged 80 µg/kg total mercury against 520 µg/kg in natural adult yellowtail.^{15Watanabe T, Hayashi T, Matsuda R, Akiyama H, Teshima R · 2017Surveillance of Total Mercury and Methylmercury Concentrations in Retail FishFood Hygiene and Safety ScienceRead source →} Farmed rather than wild Atlantic salmon for lower mercury (evidence from fish): farmed salmon averaged 18 µg/kg total mercury against 56 µg/kg in wild salmon, while arsenic was 860 against 2,560 µg/kg.^{16Unknown authors · 2020PCBs and Heavy Metals in Farmed, Escaped and WildPeer-reviewed articleRead source →}

About this table

ControlMaterialEffectsEvidence

Control

Material

Effects

Evidence

Select smaller fish within a speciescapture and landing · As reported

Fish

Hg_unspecified · Decreased

1

Jermilova et al. 2025

HMI source record · Original source

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

Effects and comparators

Mercury (speciation not reported)DecreasedLower in smaller fish (observational)Mean muscle mercuryLarge versus small pike, GSL OutletFish muscle, wet weightHigh · HMI calculates the relative change from the retained source means: (300 − 740) / 740 × 100 = -59.5%. This is a descriptive contrast of means; no confidence interval or significance test is inferred.

Large (≥600 mm) versus small (<600 mm) pike, same lake 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

Modelled mean mercury in pike under 600 mm was about two to three times lower than in pike of 600 mm or longer.

Context	Selected control
Material	Northern pike, Great Slave Lake, Canada
Stage	capture and landing
Audience	Ingredient suppliers · Brands · Consumers
Period	As reported
Conditions	Freshwater predatory fish; one basin.
Tested scale	Monitoring dataset
Sample units	Source sampling units; no independent intervention units unless stated.
Trade-offs	Other metals, nutrition and cost not quantified unless stated.
Verification	Confirm with species-specific lot results on wet weight naming the analyte species.

Design, applicability and operating conditions

Observational comparison. Freshwater predatory fish; one basin.

One study family.

As reported by the source

Reduces the metal in fish as caught, sold or eaten, or detects it before release.

Source measurements and linked outcomes

Analyte	Period	Effect	Converted values	Original means (SD)	Basis	Locator
Mercury (speciation not reported) (Hg_unspecified)	As reported	Lower in smaller fish (observational)	740 → 300 µg/kg	Absolute values unextracted	Fish muscle, wet weight	Results, Risk to human health

Model-based means from monitoring data; mercury form not stated.

No percentage calculated unless shown in outcomes.

Wet weight unless stated.

Trade-offs and implementation

Not assessed unless stated.

Not assessed.

Not quantified.

Not assessed.

Applicability and verification

Freshwater predatory fish; one basin.

Lot testing.

See source.

Extraction limits and next actions

Unresolved field	Next action
controlled intervention effect	Keep effects unquantified unless measured in the source.

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.

Farmed rather than wild Atlantic salmon for lower mercuryaquaculture · As reported

Fish

tHg · Decreased

As_unspecified · Decreased

1

Lerøy salmon study 2020

HMI source record · Original source

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

Effects and comparators

Total mercuryDecreasedLower in farmed salmon (observational)Mean fillet total mercuryWild versus farmedFish muscle, wet weightHigh · HMI calculates the relative change from the retained source means: (18.1 − 56.3) / 56.3 × 100 = -67.9%. This is a descriptive contrast of means; no confidence interval or significance test is inferred.

Arsenic (speciation not reported)DecreasedLower in farmed salmon (observational)Mean fillet arsenicWild versus farmedFish muscle, wet weightHigh · HMI calculates the relative change from the retained source means: (860 − 2560) / 2560 × 100 = -66.4%. This is a descriptive contrast of means; no confidence interval or significance test is inferred.

Farmed versus wild salmon from the same coast, 2017–2018.

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

Farmed salmon averaged 18 µg/kg total mercury against 56 µg/kg in wild salmon, while arsenic was 860 against 2,560 µg/kg.

Context	Selected control
Material	Atlantic salmon fillets, northern Norway
Stage	aquaculture
Audience	Ingredient suppliers · Brands
Period	As reported
Conditions	One farm and one wild stock.
Tested scale	Field comparison
Sample units	Source sampling units; no independent intervention units unless stated.
Trade-offs	Other metals, nutrition and cost not quantified unless stated.
Verification	Confirm with species-specific lot results on wet weight naming the analyte species.

Design, applicability and operating conditions

Observational comparison. One farm and one wild stock.

One study family.

As reported by the source

Reduces the metal in fish as caught, sold or eaten, 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	Lower in farmed salmon (observational)	56.3 → 18.1 µg/kg	Absolute values unextracted	Fish muscle, wet weight	Table 5
Arsenic (speciation not reported) (As_unspecified)	As reported	Lower in farmed salmon (observational)	2560 → 860 µg/kg	Absolute values unextracted	Fish muscle, wet weight	Table 5

Observational; farm feed and site not varied.

No percentage calculated unless shown in outcomes.

Wet weight unless stated.

Trade-offs and implementation

Not assessed unless stated.

Not assessed.

Not quantified.

Not assessed.

Applicability and verification

One farm and one wild stock.

Lot testing.

See source.

Extraction limits and next actions

Unresolved field	Next action
controlled intervention effect	Keep effects unquantified unless measured in the source.

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.

Use resin-coated cans for fishpackaging and storage · As reported

Fish

Sn · Decreased

1

Trandafir et al. 2012

HMI source record · Original source

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

Effects and comparators

Total tinDecreasedLow tin in coated cansTin in canned tunaCoated tuna canFish muscle, wet weightNot quantified · 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.

Coated tuna cans versus acidic fruit and vegetable cans.

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

Tuna in resin-coated cans had 700 µg/kg tin against up to 73,680 µg/kg in acidic tomato products in uncoated cans.

Context	Selected control
Material	Canned tuna and other canned foods
Stage	packaging and storage
Audience	Ingredient suppliers · Brands
Period	As reported
Conditions	Canned fish.
Tested scale	Market survey
Sample units	Source sampling units; no independent intervention units unless stated.
Trade-offs	Other metals, nutrition and cost not quantified unless stated.
Verification	Confirm with species-specific lot results on wet weight naming the analyte species.

Design, applicability and operating conditions

Observational comparison. Canned fish.

One study family.

As reported by the source

Reduces the metal in fish as caught, sold or eaten, or detects it before release.

Source measurements and linked outcomes

Analyte	Period	Effect	Converted values	Original means (SD)	Basis	Locator
Total tin (Sn)	As reported	Low tin in coated cans	Numerical baseline not extracted	Absolute values unextracted	Fish muscle, wet weight	Table 3

Different foods compared; not a controlled can trial.

No percentage calculated unless shown in outcomes.

Wet weight unless stated.

Trade-offs and implementation

Not assessed unless stated.

Not assessed.

Not quantified.

Not assessed.

Applicability and verification

Canned fish.

Lot testing.

See source.

Extraction limits and next actions

Unresolved field	Next action
controlled intervention effect	Keep effects unquantified unless measured in the source.

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.

Lot sampling for methylmercury with total mercury screeninglot acceptance and release · As reported

Fish

MeHg · Context

Guidance

Codex CCCF17 2024

HMI source record · Original source

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

Effects and comparators

MethylmercuryDetection, not removalLot compliance decisionSampling planFish muscle, wet 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.

Codex methylmercury limits (tuna 1,200 µg/kg; shark 1,600 µg/kg).

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

Lots are grouped by one species and comparable size; a total mercury result at or below the methylmercury limit is compliant, otherwise methylmercury is measured.

Context	Selected control
Material	Fish lots in trade
Stage	lot acceptance and release
Audience	Ingredient suppliers · Brands
Period	As reported
Conditions	International trade lots.
Tested scale	Official guidance
Sample units	Source sampling units; no independent intervention units unless stated.
Trade-offs	Other metals, nutrition and cost not quantified unless stated.
Verification	Confirm with species-specific lot results on wet weight naming the analyte species.

Design, applicability and operating conditions

Official guidance. International trade lots.

One study family.

As reported by the source

Reduces the metal in fish as caught, sold or eaten, or detects it before release.

Source measurements and linked outcomes

Analyte	Period	Effect	Converted values	Original means (SD)	Basis	Locator
Methylmercury (MeHg)	As reported	Detection, not removal	Numerical baseline not extracted	Absolute values unextracted	Fish muscle, wet weight	Appendix III

Guidance; no measured effect.

No percentage calculated unless shown in outcomes.

Wet weight unless stated.

Trade-offs and implementation

Not assessed unless stated.

Not assessed.

Not quantified.

Not assessed.

Applicability and verification

International trade lots.

Lot testing.

See source.

Extraction limits and next actions

Unresolved field	Next action
controlled intervention effect	Keep effects unquantified unless measured in the source.

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 younger fish of the same speciessourcing and procurement · As reported

Fish

tHg · Decreased

1

Watanabe 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 mercuryDecreasedLower in young fish (observational)Mean total mercuryAdult versus young yellowtailFish muscle, wet weightHigh · HMI calculates the relative change from the retained source means: (80 − 520) / 520 × 100 = -84.6%. This is a descriptive contrast of means; no confidence interval or significance test is inferred.

Young versus adult yellowtail at retail, 2014–2015.

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

Young yellowtail (inada) averaged 80 µg/kg total mercury against 520 µg/kg in natural adult yellowtail.

Context	Selected control
Material	Retail yellowtail, Japan
Stage	sourcing and procurement
Audience	Ingredient suppliers · Brands
Period	As reported
Conditions	One species and market.
Tested scale	Retail survey
Sample units	Source sampling units; no independent intervention units unless stated.
Trade-offs	Other metals, nutrition and cost not quantified unless stated.
Verification	Confirm with species-specific lot results on wet weight naming the analyte species.

Design, applicability and operating conditions

Observational comparison. One species and market.

One study family.

As reported by the source

Reduces the metal in fish as caught, sold or eaten, 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	Lower in young fish (observational)	520 → 80 µg/kg	Absolute values unextracted	Fish muscle, wet weight	Results 2, p. 84

Retail sampling; sizes not standardised.

No percentage calculated unless shown in outcomes.

Wet weight unless stated.

Trade-offs and implementation

Not assessed unless stated.

Not assessed.

Not quantified.

Not assessed.

Applicability and verification

One species and market.

Lot testing.

See source.

Extraction limits and next actions

Unresolved field	Next action
controlled intervention effect	Keep effects unquantified unless measured in the source.

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.

Cysteine soaking of tuna meatfood processing · As reported

Fish

tHg · Decreased

1

Mercury removal study 2024

HMI source record · Original source

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

Effects and comparators

Total mercuryDecreasedAbout 13–38% extracted (laboratory)Mercury removed from tuna meatTreated versus untreatedFish muscle, wet weightNot quantified · 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.

Untreated control tuna.

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

Soaking in 1.2% cysteine solution extracted about 13% of mercury from whole canned tuna and 36–38% from minced canned tuna.

Context	Selected control
Material	Canned and fresh tuna
Stage	food processing
Audience	Ingredient suppliers · Brands
Period	As reported
Conditions	Laboratory treatment; not an approved process.
Tested scale	Laboratory
Sample units	Source sampling units; no independent intervention units unless stated.
Trade-offs	Other metals, nutrition and cost not quantified unless stated.
Verification	Confirm with species-specific lot results on wet weight naming the analyte species.

Design, applicability and operating conditions

Measured comparison. Laboratory treatment; not an approved process.

One study family.

As reported by the source

Reduces the metal in fish as caught, sold or eaten, 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	About 13–38% extracted (laboratory)	Numerical baseline not extracted	Absolute values unextracted	Fish muscle, wet weight	Figures 2–5

Values read from figures.

No percentage calculated unless shown in outcomes.

Wet weight unless stated.

Trade-offs and implementation

Not assessed unless stated.

Not assessed.

Not quantified.

Not assessed.

Applicability and verification

Laboratory treatment; not an approved process.

Lot testing.

See source.

Extraction limits and next actions

Unresolved field	Next action
controlled intervention effect	Keep effects unquantified unless measured in the source.

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.

Choose lower-mercury speciesdietary exposure · As reported

Fish

MeHg · Context

Guidance

FDA/EPA fish advice

HMI source record · Original source

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

Effects and comparators

MethylmercuryLower intake by species choice (guidance)Dietary methylmercuryCategory choiceFish muscle, wet 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.

Best Choices versus Choices to Avoid categories.

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

Two to three servings a week from Best Choices such as salmon, sardines, cod and tilapia; avoid shark, swordfish, king mackerel, marlin, orange roughy, Gulf tilefish and bigeye tuna.

Context	Selected control
Material	Fish eaten by pregnant women and children
Stage	dietary exposure
Audience	Consumers
Period	As reported
Conditions	US consumers, pregnancy and childhood.
Tested scale	Official guidance
Sample units	Source sampling units; no independent intervention units unless stated.
Trade-offs	Other metals, nutrition and cost not quantified unless stated.
Verification	Confirm with species-specific lot results on wet weight naming the analyte species.

Design, applicability and operating conditions

Official guidance. US consumers, pregnancy and childhood.

One study family.

As reported by the source

Reduces the metal in fish as caught, sold or eaten, or detects it before release.

Source measurements and linked outcomes

Analyte	Period	Effect	Converted values	Original means (SD)	Basis	Locator
Methylmercury (MeHg)	As reported	Lower intake by species choice (guidance)	Numerical baseline not extracted	Absolute values unextracted	Fish muscle, wet weight	Advice chart

Guidance; categories based on FDA monitoring.

No percentage calculated unless shown in outcomes.

Wet weight unless stated.

Trade-offs and implementation

Not assessed unless stated.

Not assessed.

Not quantified.

Not assessed.

Applicability and verification

US consumers, pregnancy and childhood.

Lot testing.

See source.

Extraction limits and next actions

Unresolved field	Next action
controlled intervention effect	Keep effects unquantified unless measured in the source.

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

Metals do not move together, so a lot that passes a lead limit says little about cadmium, arsenic or nickel unless those are tested as well.

Testing catfish for metals

Results depend on the method and its reporting limit. Reporting limits for lead ranged from 3 µg/kg (WHO GEMS/Food) to 3,000 µg/kg (WHO GEMS/Food), so a non-detect from a less sensitive method says much less.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →} Reporting limits for cadmium ranged from 0.9 µg/kg (WHO GEMS/Food) to 1,000 µg/kg (WHO GEMS/Food), so a non-detect from a less sensitive method says much less.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →} Reporting limits for total arsenic ranged from 3 µg/kg (FDA Total Diet Study) to 50 µg/kg (WHO GEMS/Food), so a non-detect from a less sensitive method says much less.^{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 →}

A useful lot result names the form, the basis and a quantification limit well below the limit that applies.

Buying and verifying catfish

No maximum level for metals in catfish was verified from primary text for this page; buyers should confirm the limit that applies in the destination market.

Exposure from catfish

No source in the library converted catfish concentrations into a verified estimate of intake for a defined population. Concentrations describe the food, not individual risk.

Evidence review and remaining gaps

Every source record that names catfish was decided on its content: 21 occurrence extracted, 21 records in all. The occurrence table renders every extracted result; held values remain visible with their reason.

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.

Catfish FAQs

What heavy metals are found in catfish?

The library reports lead, cadmium, total arsenic, inorganic arsenic, total mercury, methylmercury, nickel, chromium, aluminium, uranium, Cu, Fe, Zn, Se, organotin_DBT, organotin_DPT, organotin_MBT, organotin_MPT, organotin_TBT and organotin_TPT in catfish, most often lead, cadmium and total arsenic.^{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 →}^{3Islam 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 →}^{4Simionov IA, Calmuc M, Iticescu C, Calmuc V, Georgescu PL, Faggio C, Petrea SM · 2023Human health risk assessment of potentially toxic elements and microplastics accumulation in products from the Danube River Basin fish marketEnvironmental Toxicology and PharmacologyRead source →} WHO GEMS/Food submissions reported lead in catfish, as sold from 105 results in 3 reporting regions, with a subgroup median of 6.6 µg/kg.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →}

Which origins or products of catfish measured lowest?

In one study, total arsenic across 5 groups of catfish ranged from 42 µg/kg (Nandail (Kalai) river fish) to 524 µg/kg (Tulshiganga (Akkelpur) river fish); the lowest is the lowest observed in that study, not an established sourcing preference.^{10Unknown authors · 2022Arsenic Contamination in Soil, Vegetable, Groundwater, and Riverine FishPeer-reviewed articleRead source →} In another study, nickel across 4 groups of catfish ranged from 750 µg/kg (landing site Jangwani ziwani) to 800 µg/kg (landing site Mfulo wa Ng’ombe); the lowest is the lowest observed in that study, not an established sourcing preference.^{9Sawe S, Amasi A, Wynants M · 2023Assessment of Potentially Toxic Metals in Fish from Lake Manyara, Northern TanzaniaBulletin of Environmental Contamination and ToxicologyRead source →}

How much of the arsenic in catfish is inorganic?

Inorganic arsenic, the more toxic form, was measured in 2 results from 1 source, far fewer than total arsenic.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →} WHO GEMS/Food submissions reported inorganic arsenic in catfish, as sold from 2 results in 2 reporting regions, with subgroup medians below 20 µg/kg, mostly non-detects.^{1World Health Organization · 2026GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead 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
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
Human health risk assessment of potentially toxic elements and microplastics accumulation in products from the Danube River Basin fish marketSimionov IA, Calmuc M, Iticescu C, Calmuc V, Georgescu PL, Faggio C, et al. · Environmental Toxicology and Pharmacology · 2023 · doi.org/10.1016/j.etap.2023.104307Peer-reviewed
Toxic Heavy Metals and Their Risk Assessment of Exposure in Selected Freshwater and Marine Fish in ThailandSirisangarunroj P, Monboonpitak N, Karnpanit W, Sridonpai P, Singhato A, Laitip N, et al. · Foods 2023, 12, 3967 · 2023 · doi.org/10.3390/foods12213967Peer-reviewed
Variability in Levels of Heavy Metals in Water and FishUnknown authors · Peer-reviewed article · 2015 · doi.org/10.5296/jbls.v6i2.7602Peer-reviewed
International Journal of Fisheries and Aquatic Studies 2021; 9(4): 230-233Unknown authors · Peer-reviewed article · 2021 · doi.org/10.22271/fish.2021.v9.i4c.2540Peer-reviewed
Infants’ and young children’s dietary exposures to lead and cadmium: FDA total diet study 2018-2020Spungen JH and et al. · Food Additives & Contaminants: Part A · 2024 · doi.org/10.1080/19440049.2024.2396910Peer-reviewed
Assessment of Potentially Toxic Metals in Fish from Lake Manyara, Northern TanzaniaSawe S, Amasi A, and Wynants M · Bulletin of Environmental Contamination and Toxicology · 2023 · doi.org/10.1007/s00128-023-03794-6Peer-reviewed
Arsenic Contamination in Soil, Vegetable, Groundwater, and Riverine FishUnknown authors · Peer-reviewed article · 2022 · doi.org/10.47540/ijsei.v3i1.427Peer-reviewed
Assessing mercury exposure to water and fish of the Mackenzie watershed using a Bayesian network analysisJermilova U, Kirk JL, Moe SJ, Landis WG, Sharpe E, McGovern M, et al. · Integrated Environmental Assessment and Management · 2025 · doi.org/10.1093/inteam/vjae011Peer-reviewed
Determination of Tin in Canned Foods by Inductively Coupled Plasma-Mass SpectrometryTrandafir I, Nour V, and Ionica ME · Polish Journal of Environmental Studies · 2012 · www.pjoes.comPeer-reviewed
Report of the 17th Session of the Codex Committee on Contaminants in Foods (REP24/CF17)Codex Alimentarius Commission, Codex Committee on Contaminants in Foods · Joint FAO/WHO Food Standards Programme, Codex Alimentarius Commission · 2024 · www.fao.orgGovernment
Advice About Eating Fish — For Those Who Might Become or Are Pregnant or Breastfeeding and Children Ages 1 to 11 YearsU.S. Food and Drug Administration and U.S. Environmental Protection Agency · U.S. FDA and U.S. EPA · 2017 · www.fda.govGovernment
Surveillance of Total Mercury and Methylmercury Concentrations in Retail FishWatanabe T, Hayashi T, Matsuda R, Akiyama H, and Teshima R · Food Hygiene and Safety Science · 2017 · doi.org/10.3358/shokueishi.58.80Peer-reviewed
PCBs and Heavy Metals in Farmed, Escaped and WildUnknown authors · Peer-reviewed article · 2020 · doi.org/10.3390/foods9121901Peer-reviewed

Sources

Browse Catfish 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 catfish record in the library: 21 occurrence sources, references by form and basis, same-study contrasts and stage-led controls.

Graph View

1

GEMS/Food Contaminants database heavy-metal exports

2

FY2018-FY2020 TDS Elements Analytical Results

3

The concentration, source and potential human health risk of heavy metals in the commonly consumed foods in Bangladesh

4

Human health risk assessment of potentially toxic elements and microplastics accumulation in products from the Danube River Basin fish market

5

Toxic Heavy Metals and Their Risk Assessment of Exposure in Selected Freshwater and Marine Fish in Thailand

6

Variability in Levels of Heavy Metals in Water and Fish

Food and Drug Administration

7

International Journal of Fisheries and Aquatic Studies 2021; 9(4): 230-233

8

Infants’ and young children’s dietary exposures to lead and cadmium: FDA total diet study 2018-2020

9

Assessment of Potentially Toxic Metals in Fish from Lake Manyara, Northern Tanzania

10

Arsenic Contamination in Soil, Vegetable, Groundwater, and Riverine Fish

11

Assessing mercury exposure to water and fish of the Mackenzie watershed using a Bayesian network analysis

12

Determination of Tin in Canned Foods by Inductively Coupled Plasma-Mass Spectrometry

13

Codex Alimentarius Commission

Report of the 17th Session of the Codex Committee on Contaminants in Foods (REP24/CF17)

14

Environmental Protection Agency

Advice About Eating Fish — For Those Who Might Become or Are Pregnant or Breastfeeding and Children Ages 1 to 11 Years

15

Surveillance of Total Mercury and Methylmercury Concentrations in Retail Fish

16

PCBs and Heavy Metals in Farmed, Escaped and Wild