Oysters in the HMI library has 569 reported results for lead, cadmium, total arsenic, inorganic arsenic, dimethylarsinic acid, monomethylarsonic acid, total mercury, methylmercury, nickel, chromium, aluminium, tin, antimony, Cu, Zn, V, Se, AsB, AsC, AsIII, AsV, DBT, DBT_as_Sn, DOT, DPhT, DPhT_as_Sn, MBT, MBT_as_Sn, MPhT, MPhT_as_Sn, OTC_sum_as_Sn, Sn_total_organotin, sumBT, sumOTC, sumPhT, TBT, TBT_as_Sn, TBT+DBT+TPhT, TMA, TPhT, TPhT_as_Sn and TPT from 29 sources.1GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →2Heavy Metals Contamination in Shellfish: Benefit-Risk Evaluation in Central ItalyFoodsRead source →3Heavy metals in seafood purchased from a fishery market in HungaryFood Additives & Contaminants: Part BRead source →4Heavy-metal contents in oysters (Crassostrea gigas) cultivated on the southeastern coast of the Gulf of California, MexicoHidrobiologicaRead source →5Heavy metal levels in New Zealand molluscsNew Zealand Journal of Marine and Freshwater Research 9(4), 467-481Read source →6Lead and other heavy metals (cadmium and mercury) accumulation in bivalve mollusks (Mytilus galloprovincialis, Ruditapes spp. and Crassostrea gigas) sampled in Sardinia in 2008-2012Italian Journal of Food Safety 2013; 2:e49 (pp. 182-187)Read source →
-
Metals measured:
Lead, cadmium, total arsenic, inorganic arsenic, dimethylarsinic acid and monomethylarsonic acid and others, in 569 results from 29 sources.1GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →2Heavy Metals Contamination in Shellfish: Benefit-Risk Evaluation in Central ItalyFoodsRead source →3Heavy metals in seafood purchased from a fishery market in HungaryFood Additives & Contaminants: Part BRead source →4Heavy-metal contents in oysters (Crassostrea gigas) cultivated on the southeastern coast of the Gulf of California, MexicoHidrobiologicaRead source →
-
Main drivers:
Oysters, as sold from water-soluble had TMA higher at 6,150 µg/kg, against 430 µg/kg for lipid-soluble in the same study.7Distribution of inorganic arsenic and methylated arsenic in marine organismsApplied Organometallic ChemistryRead source →
-
Practical framing:
Ask for lot results with a quantification limit well below the limit that applies in the destination market.1GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →2Heavy Metals Contamination in Shellfish: Benefit-Risk Evaluation in Central ItalyFoodsRead source →3Heavy metals in seafood purchased from a fishery market in HungaryFood Additives & Contaminants: Part BRead source →4Heavy-metal contents in oysters (Crassostrea gigas) cultivated on the southeastern coast of the Gulf of California, MexicoHidrobiologicaRead source →
Oysters overview
Oysters in the HMI library has 569 reported results for lead, cadmium, total arsenic, inorganic arsenic, dimethylarsinic acid, monomethylarsonic acid, total mercury, methylmercury, nickel, chromium, aluminium, tin, antimony, Cu, Zn, V, Se, AsB, AsC, AsIII, AsV, DBT, DBT_as_Sn, DOT, DPhT, DPhT_as_Sn, MBT, MBT_as_Sn, MPhT, MPhT_as_Sn, OTC_sum_as_Sn, Sn_total_organotin, sumBT, sumOTC, sumPhT, TBT, TBT_as_Sn, TBT+DBT+TPhT, TMA, TPhT, TPhT_as_Sn and TPT from 29 sources.1GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →2Heavy Metals Contamination in Shellfish: Benefit-Risk Evaluation in Central ItalyFoodsRead source →3Heavy metals in seafood purchased from a fishery market in HungaryFood Additives & Contaminants: Part BRead source →4Heavy-metal contents in oysters (Crassostrea gigas) cultivated on the southeastern coast of the Gulf of California, MexicoHidrobiologicaRead source →5Heavy metal levels in New Zealand molluscsNew Zealand Journal of Marine and Freshwater Research 9(4), 467-481Read source →6Lead and other heavy metals (cadmium and mercury) accumulation in bivalve mollusks (Mytilus galloprovincialis, Ruditapes spp. and Crassostrea gigas) sampled in Sardinia in 2008-2012Italian Journal of Food Safety 2013; 2:e49 (pp. 182-187)Read source → WHO GEMS/Food submissions reported lead in oysters, as sold from 1,311 results in 3 reporting regions, with subgroup medians from 13 to 205 µg/kg.1GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source → For cadmium, GEMS/Food gave subgroup medians from 29.5 to 1,200 µg/kg from 1,296 results.1GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →
Across 7 other studies of ordinary farms and markets, reported lead means and medians on an as-sold or fresh-weight basis ranged from 100 µg/kg (Singhato et al. 2025) to 3,160 µg/kg (Martin et al. 2017).4Heavy-metal contents in oysters (Crassostrea gigas) cultivated on the southeastern coast of the Gulf of California, MexicoHidrobiologicaRead source →8Risk Assessment of Toxic Heavy Metal Exposure in Selected Seafood Species from ThailandFoodsRead source → For cadmium, 9 studies on an as-sold or fresh-weight basis reported means and medians from 27 µg/kg (Valencia et al. 2021) to 16,200 µg/kg (Martin et al. 2017).4Heavy-metal contents in oysters (Crassostrea gigas) cultivated on the southeastern coast of the Gulf of California, MexicoHidrobiologicaRead source →9Heavy metal accumulation and risk assessment of lead and cadmium in cultured oysters (Crassostrea iredalei) of Cañacao Bay, PhilippinesSustinere: Journal of Environment and Sustainability 5(2), 64-78Read source → Higher results came from contaminated or exposed settings rather than ordinary supply. Oysters, as sold from water-soluble had TMA higher at 6,150 µg/kg, against 430 µg/kg for lipid-soluble in the same study.7Distribution of inorganic arsenic and methylated arsenic in marine organismsApplied Organometallic ChemistryRead source →
For a buyer the practical points are the form bought, the basis a result is reported on, where the oysters came from and the laboratory’s reporting limit. Testing finds contamination but does not remove it.
What counts as oysters
This page covers oysters, as sold (569 results).1GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →2Heavy Metals Contamination in Shellfish: Benefit-Risk Evaluation in Central ItalyFoodsRead source →3Heavy metals in seafood purchased from a fishery market in HungaryFood Additives & Contaminants: Part BRead source →4Heavy-metal contents in oysters (Crassostrea gigas) cultivated on the southeastern coast of the Gulf of California, MexicoHidrobiologicaRead source →5Heavy metal levels in New Zealand molluscsNew Zealand Journal of Marine and Freshwater Research 9(4), 467-481Read source →6Lead and other heavy metals (cadmium and mercury) accumulation in bivalve mollusks (Mytilus galloprovincialis, Ruditapes spp. and Crassostrea gigas) sampled in Sardinia in 2008-2012Italian Journal of Food Safety 2013; 2:e49 (pp. 182-187)Read 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 oysters
The table holds every extracted oysters result: one row for each statistic a source reports for a form, group and metal, 569 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.1GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →2Heavy Metals Contamination in Shellfish: Benefit-Risk Evaluation in Central ItalyFoodsRead source →3Heavy metals in seafood purchased from a fishery market in HungaryFood Additives & Contaminants: Part BRead source →4Heavy-metal contents in oysters (Crassostrea gigas) cultivated on the southeastern coast of the Gulf of California, MexicoHidrobiologicaRead source →5Heavy metal levels in New Zealand molluscsNew Zealand Journal of Marine and Freshwater Research 9(4), 467-481Read source →6Lead and other heavy metals (cadmium and mercury) accumulation in bivalve mollusks (Mytilus galloprovincialis, Ruditapes spp. and Crassostrea gigas) sampled in Sardinia in 2008-2012Italian Journal of Food Safety 2013; 2:e49 (pp. 182-187)Read 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.1GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →
113 rows can be rated against an HMI reference for the same form and basis, 267 rows have a direct same-study comparison, and the rest stay unrated with the reason recorded. 17 values from 2 sources failed a check against their own source and are shown but not compared.10Studies on seasonal pollution of heavy metals in water, sediment, fish and oyster from the Meiliang Bay of Taihu Lake in ChinaChemosphereRead source →11Organotin contamination in commercial and wild oysters from China: Increasing occurrence of triphenyltinScience of the Total EnvironmentRead source →
Comparison methods and scope
Each row is one statistic a source reports for one form of oysters, 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.
First displayed analyte: Lead: 68 findings from 12 sources. Each row retains its statistic and measurement basis.
Filter findings
555 of 555 findings · 42 analytes
About this table
| Food form | Collection scope | Finding (µg/kg) | Comparison | Evidence |
|---|---|---|---|---|
65 findings · 12 studies · 3 spread figures folded in | ||||
| Oysters, as soldWHO GEMS/Food | EURO1998–2019As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | EURO2000As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | EURO2003–2017As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | PAHO2007–2017As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | WPRO2007–2009As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | WPRO2010–2011As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | WPRO2000As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | WPRO2010As sold / fresh | median. | ||
| Oysters, as soldBarchiesi et al. 2020 | Italy, 20172017–2019As sold / fresh | mean.Same samples: 90–400 µg/kg (range) | ||
| Oysters, as soldBarchiesi et al. 2020 | Italy, 20172017–2019As sold / fresh | range. | ||
| Oysters, as soldBarchiesi et al. 2020 | Italy, 20182017–2019As sold / fresh | mean.Same samples: 30–780 µg/kg (range) | ||
| Oysters, as soldBarchiesi et al. 2020 | Italy, 20182017–2019As sold / fresh | range. | ||
| Oysters, as soldBarchiesi et al. 2020 | Italy, 20192017–2019As sold / fresh | mean.Same samples: 30–370 µg/kg (range) | ||
| Oysters, as soldBarchiesi et al. 2020 | Italy, 20192017–2019As sold / fresh | range. | ||
| Oysters, as soldLehel et al. 2018 | all samples2015As sold / fresh | mean. | ||
| Oysters, as soldLehel et al. 2018 | all samples2015As sold / fresh | range. | ||
| Oysters, as soldMartin et al. 2017 | April 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | August 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | December 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | July 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | June 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | March 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | May 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | mean of ten months2011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | November 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | October 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | September 20112011As sold / fresh | mean. | ||
| Oysters, as soldNielsen et al. 1975 | all sites1972–1973As sold / fresh | mean. | ||
| Oysters, as soldNielsen et al. 1975 | all sites1972–1973As sold / fresh | mean. | ||
| Oysters, as soldNielsen et al. 1975 | all sites1972–1973As sold / fresh | mean. | ||
| Oysters, as soldPiras et al. 2013 | all samples (pre-marketing and marketing), Sardinia 2008-20122008–2012As sold / fresh | median. | ||
| Oysters, as soldPiras et al. 2013 | all samples (pre-marketing and marketing), Sardinia 2008-20122008–2012As sold / fresh | mean. | ||
| Oysters, as soldRajeshkumar et al. 2018 | Autumn (seven sites, Meiliang Bay)2016As sold / fresh | mean. | ||
| Oysters, as soldRajeshkumar et al. 2018 | Spring (seven sites, Meiliang Bay)2016As sold / fresh | mean. | ||
| Oysters, as soldRajeshkumar et al. 2018 | Summer (seven sites, Meiliang Bay)2016As sold / fresh | mean. | ||
| Oysters, as soldRajeshkumar et al. 2018 | Winter (seven sites, Meiliang Bay)2016As sold / fresh | mean. | ||
| Oysters, as soldSinghato et al. 2025 | all samples2025As sold / fresh | mean. | ||
| Oysters, as soldValencia et al. 2021 | Mean of 3 stations, December2016–2017As sold / fresh | mean. | ||
| Oysters, as soldValencia et al. 2021 | Mean of 3 stations, January2016–2017As sold / fresh | not detected. | ||
| Oysters, as soldValencia et al. 2021 | Mean of 3 stations, November2016–2017As sold / fresh | mean. | ||
| Oysters, as soldValencia et al. 2021 | Mean of 3 stations, October2016–2017As sold / fresh | not detected. | ||
| Oysters, as soldValencia et al. 2021 | Station 1, December (pooled 15-20 oysters)2016–2017As sold / fresh | sample value. | ||
| Oysters, as soldValencia et al. 2021 | Station 1, January (pooled 15-20 oysters)2016–2017As sold / fresh | not detected. | ||
| Oysters, as soldValencia et al. 2021 | Station 1, November (pooled 15-20 oysters)2016–2017As sold / fresh | sample value. | ||
| Oysters, as soldValencia et al. 2021 | Station 1, October (pooled 15-20 oysters)2016–2017As sold / fresh | not detected. | ||
| Oysters, as soldValencia et al. 2021 | Station 2, December (pooled 15-20 oysters)2016–2017As sold / fresh | sample value. | ||
| Oysters, as soldValencia et al. 2021 | Station 2, January (pooled 15-20 oysters)2016–2017As sold / fresh | not detected. | ||
| Oysters, as soldValencia et al. 2021 | Station 2, November (pooled 15-20 oysters)2016–2017As sold / fresh | sample value. | ||
| Oysters, as soldValencia et al. 2021 | Station 2, October (pooled 15-20 oysters)2016–2017As sold / fresh | not detected. | ||
| Oysters, as soldValencia et al. 2021 | Station 3, December (pooled 15-20 oysters)2016–2017As sold / fresh | sample value. | ||
| Oysters, as soldValencia et al. 2021 | Station 3, January (pooled 15-20 oysters)2016–2017As sold / fresh | not detected. | ||
| Oysters, as soldValencia et al. 2021 | Station 3, November (pooled 15-20 oysters)2016–2017As sold / fresh | sample value. | ||
| Oysters, as soldValencia et al. 2021 | Station 3, October (pooled 15-20 oysters)2016–2017As sold / fresh | not detected. | ||
| Oysters, as soldZhao et al. 2016 | all samples2013–2014As sold / fresh | range. | ||
| Oysters, as soldMartin et al. 2017 | April 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | August 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | December 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | July 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | June 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | March 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | May 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | mean of ten months2011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | November 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | October 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | September 20112011Dry weight | mean. | ||
| Oysters, as soldOnyegeme-Okerenta et al. 2023 | Bonny River (lowest)Collection date unreportedDry weight | min. | ||
| Oysters, as soldCentre for Food Safety (Hong Kong) 2013 | all samples2010–2011Basis not stated | mean. | ||
| Oysters, as soldCentre for Food Safety (Hong Kong) 2013 | all samples2010–2011Basis not stated | mean. | ||
70 findings · 14 studies · 7 spread figures folded in | ||||
| Oysters, as soldWHO GEMS/Food | EURO2005As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | EURO1998–2019As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | EURO2000–2007As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | EURO2005–2017As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | PAHO2016As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | WPRO2010–2011As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | WPRO2000As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | WPRO2010As sold / fresh | median. | ||
| Oysters, as soldBarchiesi et al. 2020 | Italy, 20172017–2019As sold / fresh | mean.Same samples: 130–530 µg/kg (range) | ||
| Oysters, as soldBarchiesi et al. 2020 | Italy, 20172017–2019As sold / fresh | range. | ||
| Oysters, as soldBarchiesi et al. 2020 | Italy, 20182017–2019As sold / fresh | mean.Same samples: 70–840 µg/kg (range) | ||
| Oysters, as soldBarchiesi et al. 2020 | Italy, 20182017–2019As sold / fresh | range. | ||
| Oysters, as soldBarchiesi et al. 2020 | Italy, 20192017–2019As sold / fresh | mean.Same samples: 60–880 µg/kg (range) | ||
| Oysters, as soldBarchiesi et al. 2020 | Italy, 20192017–2019As sold / fresh | range. | ||
| Oysters, as soldDellal et al. 2022 | Boutalha area, winter 20182012–2020As sold / fresh | max. | ||
| Oysters, as soldDellal et al. 2022 | Boutalha oyster breeding site (St 6), Dakhla Bay2012–2020As sold / fresh | mean. | ||
| Oysters, as soldDellal et al. 2022 | Dunablanca oyster breeding site (St 3), Dakhla Bay2012–2020As sold / fresh | mean. | ||
| Oysters, as soldEFSA Panel on Contaminants in the Food Chain (CONTAM) 2009 | all samples (EU Member States and others, 2003-2007)2003–2007As sold / fresh | median. | ||
| Oysters, as soldEFSA Panel on Contaminants in the Food Chain (CONTAM) 2009 | all samples (EU Member States and others, 2003-2007)2003–2007As sold / fresh | mean.Same samples: 970 µg/kg (maximum); 90 µg/kg (percentile); 840 µg/kg (percentile) | ||
| Oysters, as soldEFSA Panel on Contaminants in the Food Chain (CONTAM) 2009 | all samples (EU Member States and others, 2003-2007)2003–2007As sold / fresh | max. | ||
| Oysters, as soldEFSA Panel on Contaminants in the Food Chain (CONTAM) 2009 | all samples (EU Member States and others, 2003-2007)2003–2007As sold / fresh | percentile. | ||
| Oysters, as soldEFSA Panel on Contaminants in the Food Chain (CONTAM) 2009 | all samples (EU Member States and others, 2003-2007)2003–2007As sold / fresh | percentile. | ||
| Oysters, as soldLehel et al. 2018 | all samples2015As sold / fresh | mean.Same samples: 150–460 µg/kg (range) | ||
| Oysters, as soldLehel et al. 2018 | all samples2015As sold / fresh | range. | ||
| Oysters, as soldMartin et al. 2017 | April 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | August 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | December 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | July 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | June 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | March 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | May 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | mean of ten months2011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | November 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | October 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | September 20112011As sold / fresh | mean. | ||
| Oysters, as soldNielsen et al. 1975 | all sites1972–1973As sold / fresh | mean. | ||
| Oysters, as soldNielsen et al. 1975 | all sites1972–1973As sold / fresh | mean. | ||
| Oysters, as soldNielsen et al. 1975 | all sites1972–1973As sold / fresh | mean. | ||
| Oysters, as soldPiras et al. 2013 | all samples (pre-marketing and marketing), Sardinia 2008-20122008–2012As sold / fresh | median. | ||
| Oysters, as soldPiras et al. 2013 | all samples (pre-marketing and marketing), Sardinia 2008-20122008–2012As sold / fresh | mean. | ||
| Oysters, as soldRajeshkumar et al. 2018 | Autumn (seven sites, Meiliang Bay)2016As sold / fresh | mean. | ||
| Oysters, as soldRajeshkumar et al. 2018 | Spring (seven sites, Meiliang Bay)2016As sold / fresh | mean. | ||
| Oysters, as soldRajeshkumar et al. 2018 | Summer (seven sites, Meiliang Bay)2016As sold / fresh | mean. | ||
| Oysters, as soldRajeshkumar et al. 2018 | Winter (seven sites, Meiliang Bay)2016As sold / fresh | mean. | ||
| Oysters, as soldSinghato et al. 2025 | all samples2025As sold / fresh | mean. | ||
| Oysters, as soldValencia et al. 2021 | Mean of 3 stations, December2016–2017As sold / fresh | mean. | ||
| Oysters, as soldValencia et al. 2021 | Mean of 3 stations, January2016–2017As sold / fresh | mean. | ||
| Oysters, as soldValencia et al. 2021 | Mean of 3 stations, November2016–2017As sold / fresh | mean. | ||
| Oysters, as soldValencia et al. 2021 | Mean of 3 stations, October2016–2017As sold / fresh | mean. | ||
| Oysters, as soldValencia et al. 2021 | Station 1, December (pooled 15-20 oysters)2016–2017As sold / fresh | sample value. | ||
| Oysters, as soldValencia et al. 2021 | Station 1, January (pooled 15-20 oysters)2016–2017As sold / fresh | sample value. | ||
| Oysters, as soldValencia et al. 2021 | Station 1, November (pooled 15-20 oysters)2016–2017As sold / fresh | sample value. | ||
| Oysters, as soldValencia et al. 2021 | Station 1, October (pooled 15-20 oysters)2016–2017As sold / fresh | sample value. | ||
| Oysters, as soldValencia et al. 2021 | Station 2, December (pooled 15-20 oysters)2016–2017As sold / fresh | sample value. | ||
| Oysters, as soldValencia et al. 2021 | Station 2, January (pooled 15-20 oysters)2016–2017As sold / fresh | sample value. | ||
| Oysters, as soldValencia et al. 2021 | Station 2, November (pooled 15-20 oysters)2016–2017As sold / fresh | sample value. | ||
| Oysters, as soldValencia et al. 2021 | Station 2, October (pooled 15-20 oysters)2016–2017As sold / fresh | sample value. | ||
| Oysters, as soldValencia et al. 2021 | Station 3, December (pooled 15-20 oysters)2016–2017As sold / fresh | sample value. | ||
| Oysters, as soldValencia et al. 2021 | Station 3, January (pooled 15-20 oysters)2016–2017As sold / fresh | sample value. | ||
| Oysters, as soldValencia et al. 2021 | Station 3, November (pooled 15-20 oysters)2016–2017As sold / fresh | sample value. | ||
| Oysters, as soldValencia et al. 2021 | Station 3, October (pooled 15-20 oysters)2016–2017As sold / fresh | sample value. | ||
| Oysters, as soldZhao et al. 2016 | all samples2013–2014As sold / fresh | range. | ||
| Oysters, as soldMartin et al. 2017 | April 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | August 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | December 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | July 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | June 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | March 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | May 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | mean of ten months2011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | November 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | October 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | September 20112011Dry weight | mean. | ||
| Oysters, as soldCentre for Food Safety (Hong Kong) 2013 | all samples2010–2011Basis not stated | mean. | ||
| Oysters, as soldCentre for Food Safety (Hong Kong) 2013 | all samples2010–2011Basis not stated | mean. | ||
| Oysters, as soldJoint FAO/WHO Expert Committee on Food Additives 2006 | aggregated national datasets submitted to GEMS/FoodCollection date unreportedBasis not stated | mean. | ||
| Oysters, as soldJoint FAO/WHO Expert Committee on Food Additives 2006 | aggregated national datasets submitted to GEMS/FoodCollection date unreportedBasis not stated | mean. | ||
43 findings · 10 studies · 1 spread figure folded in | ||||
| Oysters, as soldWHO GEMS/Food | EURO2003–2023As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | EURO2000–2022As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | EURO2003–2017As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | WPRO2009As sold / fresh | median. | ||
| Oysters, as soldLehel et al. 2018 | all samples2015As sold / fresh | mean.Same samples: 1,480–6,470 µg/kg (range) | ||
| Oysters, as soldLehel et al. 2018 | all samples2015As sold / fresh | range. | ||
| Oysters, as soldMartin et al. 2017 | April 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | August 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | December 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | July 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | June 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | March 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | May 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | mean of ten months2011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | November 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | October 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | September 20112011As sold / fresh | mean. | ||
| Oysters, as soldMatsumoto-Tanibuchi et al. 2019 | all samplesCollection date unreportedAs sold / fresh | mean. | ||
| Oysters, as soldMatsumoto-Tanibuchi et al. 2019 | all samplesCollection date unreportedAs sold / fresh | mean. | ||
| Oysters, as soldMatsumoto-Tanibuchi et al. 2019 | all samplesCollection date unreportedAs sold / fresh | mean. | ||
| Oysters, as soldMatsumoto-Tanibuchi et al. 2019 | all samplesCollection date unreportedAs sold / fresh | mean. | ||
| Oysters, as soldShiomi et al. 1988 | experiment 1, live specimens from a retail supplier, JapanCollection date unreportedAs sold / fresh | sample value. | ||
| Oysters, as soldShiomi et al. 1988 | experiment 1, live specimens from a retail supplier, JapanCollection date unreportedAs sold / fresh | sample value. | ||
| Oysters, as soldShiomi et al. 1988 | experiment 1, live specimens from a retail supplier, JapanCollection date unreportedAs sold / fresh | sample value. | ||
| Oysters, as soldShiomi et al. 1988 | experiment 1, live specimens from a retail supplier, JapanCollection date unreportedAs sold / fresh | sample value. | ||
| Oysters, as soldShiomi et al. 1988 | experiment 2, live specimens from a retail supplier, JapanCollection date unreportedAs sold / fresh | sample value. | ||
| Oysters, as soldShiomi et al. 1988 | experiment 2, live specimens from a retail supplier, JapanCollection date unreportedAs sold / fresh | sample value. | ||
| Oysters, as soldShiomi et al. 1988 | experiment 2, live specimens from a retail supplier, JapanCollection date unreportedAs sold / fresh | sample value. | ||
| Oysters, as soldSinghato et al. 2025 | all samples2025As sold / fresh | mean. | ||
| Oysters, as soldZhao et al. 2016 | all samples2013–2014As sold / fresh | range. | ||
| Oysters, as soldFattorini et al. 2006 | Cienfuegos Bay (Cuba, Caribbean Sea)Collection date unreportedDry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | April 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | August 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | December 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | July 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | June 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | March 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | May 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | mean of ten months2011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | November 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | October 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | September 20112011Dry weight | mean. | ||
| Oysters, as soldOnyegeme-Okerenta et al. 2023 | Buguma River (highest)Collection date unreportedDry weight | max. | ||
| Oysters, as soldKaise et al. 1988 | Whole1987Basis not stated | sample value. | ||
20 findings · 6 studies | ||||
| Oysters, as soldWHO GEMS/Food | EURO2003–2023As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | EURO2007–2022As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | EURO2004–2021As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | WPRO2023As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | WPRO2020–2024As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | WPRO2008As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | WPRO2010–2022As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | WPRO2020–2024As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | WPRO2010–2022As sold / fresh | median. | ||
| Oysters, as soldMatsumoto-Tanibuchi et al. 2019 | all samplesCollection date unreportedAs sold / fresh | mean. | ||
| Oysters, as soldMatsumoto-Tanibuchi et al. 2019 | all samplesCollection date unreportedAs sold / fresh | mean. | ||
| Oysters, as soldMatsumoto-Tanibuchi et al. 2019 | all samplesCollection date unreportedAs sold / fresh | mean. | ||
| Oysters, as soldMatsumoto-Tanibuchi et al. 2019 | all samplesCollection date unreportedAs sold / fresh | not detected. | ||
| Oysters, as soldWHO GEMS/Food | PAHO2020Dry weight | median. | ||
| Oysters, as soldCentre for Food Safety FEHD HKSAR 2012 | all samples (4 sampling occasions, composites)2010–2011Basis not stated | mean. | ||
| Oysters, as soldCentre for Food Safety FEHD HKSAR 2012 | all samples (4 sampling occasions, composites)2010–2011Basis not stated | mean. | ||
| Oysters, as soldEFSA 2021 | EU occurrence data (LB)2013–2018Basis not stated | mean. | ||
| Oysters, as soldEFSA 2021 | EU occurrence data (UB)2013–2018Basis not stated | mean. | ||
| Oysters, as soldEuropean Food Safety Authority (EFSA) 2014 | European dietary-survey occurrence data2003–2013Basis not stated | mean. | ||
| Oysters, as soldKaise et al. 1988 | Whole1987Basis not stated | not detected. | ||
4 findings · 3 studies | ||||
| Oysters, as soldWHO GEMS/Food | EURO2017As sold / fresh | median. | ||
| Oysters, as soldKaise et al. 1988 | lipid-soluble1987Basis not stated | sample value. | ||
| Oysters, as soldKaise et al. 1988 | water-soluble1987Basis not stated | sample value. | ||
| Oysters, as soldPark et al. 2005 | market sampleCollection date unreportedBasis not stated | not detected. | ||
4 findings · 3 studies | ||||
| Oysters, as soldEFSA CONTAM Panel 2024 | EU market, EFSA occurrence data2012–2022Basis not stated | mean. | ||
| Oysters, as soldKaise et al. 1988 | lipid-soluble1987Basis not stated | not detected. | ||
| Oysters, as soldKaise et al. 1988 | water-soluble1987Basis not stated | not detected. | ||
| Oysters, as soldPark et al. 2005 | market sampleCollection date unreportedBasis not stated | not detected. | ||
40 findings · 8 studies · 3 spread figures folded in | ||||
| Oysters, as soldWHO GEMS/Food | EURO1998–2018As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | EURO2000As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | EURO2006–2017As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | PAHO2019–2020As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | PAHO2013–2014As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | PAHO2007–2020As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | PAHO2016As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | WPRO1982As sold / fresh | median. | ||
| Oysters, as soldBarchiesi et al. 2020 | Italy, 20172017–2019As sold / fresh | mean.Same samples: 30–110 µg/kg (range) | ||
| Oysters, as soldBarchiesi et al. 2020 | Italy, 20172017–2019As sold / fresh | range. | ||
| Oysters, as soldBarchiesi et al. 2020 | Italy, 20182017–2019As sold / fresh | mean.Same samples: 30–260 µg/kg (range) | ||
| Oysters, as soldBarchiesi et al. 2020 | Italy, 20182017–2019As sold / fresh | range. | ||
| Oysters, as soldBarchiesi et al. 2020 | Italy, 20192017–2019As sold / fresh | mean.Same samples: 30–110 µg/kg (range) | ||
| Oysters, as soldBarchiesi et al. 2020 | Italy, 20192017–2019As sold / fresh | range. | ||
| Oysters, as soldLehel et al. 2018 | all samples2015As sold / fresh | not detected. | ||
| Oysters, as soldMartin et al. 2017 | April 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | August 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | December 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | July 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | June 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | March 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | May 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | mean of ten months2011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | November 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | October 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | September 20112011As sold / fresh | mean. | ||
| Oysters, as soldNielsen et al. 1975 | all sites1972–1973As sold / fresh | mean. | ||
| Oysters, as soldNielsen et al. 1975 | all sites1972–1973As sold / fresh | mean. | ||
| Oysters, as soldPiras et al. 2013 | all samples (pre-marketing and marketing), Sardinia 2008-20122008–2012As sold / fresh | median. | ||
| Oysters, as soldPiras et al. 2013 | all samples (pre-marketing and marketing), Sardinia 2008-20122008–2012As sold / fresh | mean. | ||
| Oysters, as soldSinghato et al. 2025 | all samples2025As sold / fresh | mean. | ||
| Oysters, as soldZhao et al. 2016 | all samples2013–2014As sold / fresh | not detected. | ||
| Oysters, as soldMartin et al. 2017 | April 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | August 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | December 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | July 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | June 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | March 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | May 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | mean of ten months2011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | November 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | October 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | September 20112011Dry weight | mean. | ||
3 findings · 2 studies | ||||
| Oysters, as soldWHO GEMS/Food | PAHO2015–2016As sold / fresh | median. | ||
| Oysters, as soldCentre for Food Safety (Hong Kong) 2013 | all samples2010–2011Basis not stated | mean. | ||
| Oysters, as soldCentre for Food Safety (Hong Kong) 2013 | all samples2010–2011Basis not stated | not detected. | ||
26 findings · 4 studies | ||||
| Oysters, as soldWHO GEMS/Food | EURO2000As sold / fresh | median. | ||
| Oysters, as soldMartin et al. 2017 | April 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | August 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | December 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | July 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | June 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | March 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | May 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | mean of ten months2011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | November 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | October 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | September 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | April 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | August 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | December 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | July 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | June 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | March 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | May 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | mean of ten months2011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | November 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | October 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | September 20112011Dry weight | mean. | ||
| Oysters, as soldOnyegeme-Okerenta et al. 2023 | Bonny and Buguma (highest)Collection date unreportedDry weight | max. | ||
| Oysters, as soldCentre for Food Safety (Hong Kong) 2013 | all samples2010–2011Basis not stated | mean. | ||
| Oysters, as soldCentre for Food Safety (Hong Kong) 2013 | all samples2010–2011Basis not stated | mean. | ||
28 findings · 4 studies | ||||
| Oysters, as soldWHO GEMS/Food | EURO2000As sold / fresh | median. | ||
| Oysters, as soldMartin et al. 2017 | April 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | August 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | December 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | July 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | June 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | March 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | May 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | mean of ten months2011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | November 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | October 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | September 20112011As sold / fresh | mean. | ||
| Oysters, as soldRajeshkumar et al. 2018 | Autumn (seven sites, Meiliang Bay)2016As sold / fresh | mean. | ||
| Oysters, as soldRajeshkumar et al. 2018 | Spring (seven sites, Meiliang Bay)2016As sold / fresh | mean. | ||
| Oysters, as soldRajeshkumar et al. 2018 | Summer (seven sites, Meiliang Bay)2016As sold / fresh | mean. | ||
| Oysters, as soldRajeshkumar et al. 2018 | Winter (seven sites, Meiliang Bay)2016As sold / fresh | mean. | ||
| Oysters, as soldZhao et al. 2016 | all samples2013–2014As sold / fresh | range. | ||
| Oysters, as soldMartin et al. 2017 | April 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | August 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | December 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | July 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | June 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | March 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | May 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | mean of ten months2011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | November 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | October 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | September 20112011Dry weight | mean. | ||
4 findings · 2 studies | ||||
| Oysters, as soldWHO GEMS/Food | EURO2008–2009As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | EURO2000As sold / fresh | median. | ||
| Oysters, as soldCentre for Food Safety (Hong Kong) 2013 | all samples2010–2011Basis not stated | mean. | ||
| Oysters, as soldCentre for Food Safety (Hong Kong) 2013 | all samples2010–2011Basis not stated | mean. | ||
5 findings · 2 studies | ||||
| Oysters, as soldWHO GEMS/Food | EURO2008–2009As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | WPRO2010–2011As sold / fresh | median. | ||
| Oysters, as soldWHO GEMS/Food | WPRO2010As sold / fresh | median. | ||
| Oysters, as soldCentre for Food Safety (Hong Kong) 2013 | all samples2010–2011Basis not stated | mean. | ||
| Oysters, as soldCentre for Food Safety (Hong Kong) 2013 | all samples2010–2011Basis not stated | mean. | ||
2 findings · 1 study | ||||
| Oysters, as soldCentre for Food Safety (Hong Kong) 2013 | all samples2010–2011Basis not stated | mean. | ||
| Oysters, as soldCentre for Food Safety (Hong Kong) 2013 | all samples2010–2011Basis not stated | mean. | ||
29 findings · 3 studies | ||||
| Oysters, as soldMartin et al. 2017 | April 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | August 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | December 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | July 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | June 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | March 20112011As sold / fresh | not detected. | ||
| Oysters, as soldMartin et al. 2017 | May 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | mean of ten months2011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | November 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | October 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | September 20112011As sold / fresh | mean. | ||
| Oysters, as soldNielsen et al. 1975 | all sites1972–1973As sold / fresh | mean. | ||
| Oysters, as soldNielsen et al. 1975 | all sites1972–1973As sold / fresh | mean. | ||
| Oysters, as soldNielsen et al. 1975 | all sites1972–1973As sold / fresh | mean. | ||
| Oysters, as soldRajeshkumar et al. 2018 | Autumn (seven sites, Meiliang Bay)2016As sold / fresh | mean. | ||
| Oysters, as soldRajeshkumar et al. 2018 | Spring (seven sites, Meiliang Bay)2016As sold / fresh | mean. | ||
| Oysters, as soldRajeshkumar et al. 2018 | Summer (seven sites, Meiliang Bay)2016As sold / fresh | mean. | ||
| Oysters, as soldRajeshkumar et al. 2018 | Winter (seven sites, Meiliang Bay)2016As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | April 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | August 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | December 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | July 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | June 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | March 20112011Dry weight | not detected. | ||
| Oysters, as soldMartin et al. 2017 | May 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | mean of ten months2011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | November 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | October 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | September 20112011Dry weight | mean. | ||
25 findings · 2 studies | ||||
| Oysters, as soldMartin et al. 2017 | April 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | August 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | December 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | July 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | June 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | March 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | May 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | mean of ten months2011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | November 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | October 20112011As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | September 20112011As sold / fresh | mean. | ||
| Oysters, as soldNielsen et al. 1975 | all sites1972–1973As sold / fresh | mean. | ||
| Oysters, as soldNielsen et al. 1975 | all sites1972–1973As sold / fresh | mean. | ||
| Oysters, as soldNielsen et al. 1975 | all sites1972–1973As sold / fresh | mean. | ||
| Oysters, as soldMartin et al. 2017 | April 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | August 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | December 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | July 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | June 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | March 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | May 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | mean of ten months2011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | November 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | October 20112011Dry weight | mean. | ||
| Oysters, as soldMartin et al. 2017 | September 20112011Dry weight | mean. | ||
2 findings · 1 study | ||||
| Oysters, as soldCentre for Food Safety (Hong Kong) 2013 | all samples2010–2011Basis not stated | mean. | ||
| Oysters, as soldCentre for Food Safety (Hong Kong) 2013 | all samples2010–2011Basis not stated | mean. | ||
4 findings · 1 study | ||||
| Oysters, as soldauthors 2025 | all samples2025As sold / fresh | mean. | ||
| Oysters, as soldauthors 2025 | all samples2025Basis not stated | mean. | ||
| Oysters, as soldauthors 2025 | all samples2025Basis not stated | mean. | ||
| Oysters, as soldauthors 2025 | all samples2025Basis not stated | mean. | ||
1 finding · 1 study | ||||
| Oysters, as soldPark et al. 2005 | market sampleCollection date unreportedBasis not stated | sample value. | ||
1 finding · 1 study | ||||
| Oysters, as soldPark et al. 2005 | market sampleCollection date unreportedBasis not stated | sample value. | ||
1 finding · 1 study | ||||
| Oysters, as soldPark et al. 2005 | market sampleCollection date unreportedBasis not stated | sample value. | ||
1 finding · 1 study | ||||
| Oysters, as soldPark et al. 2005 | market sampleCollection date unreportedBasis not stated | sample value. | ||
3 findings · 3 studies | ||||
| Oysters, as soldChung et al. 2020 | all samples2017–2018As sold / fresh | mean. | ||
| Oysters, as soldUc-Peraza et al. 2022 | five Yucatán fishing sites pooled2018Dry weight | mean. | ||
| Oysters, as soldCentre for Food Safety 2019 | molluscs2017–2018Basis not stated | mean. | ||
22 findings · 1 study | ||||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S1 Dandong2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S2 Dalian2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S3 Tangshan2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S4 Yantai2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S5 Weihai2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S6 Qingdao2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S7 Lianyungang2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS1 (Table 1 row 1)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS1 (Table 1 row 3)2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS2 (Table 1 row 2)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS2 (Table 1 row 4)2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS3 (Table 1 row 5)2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS4 (Table 1 row 6)2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS5 (Table 1 row 7)2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS6 (Table 1 row 8)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S8 Ningbo2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S9 Wenzhou2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S10 Quanzhou2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S11 Xiamen2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S12 Chaozhou2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S13 Shenzhen2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S14 Beihai2014–2015Dry weight | mean. | ||
2 findings · 2 studies | ||||
| Oysters, as soldChung et al. 2020 | all samples2017–2018As sold / fresh | not detected. | ||
| Oysters, as soldCentre for Food Safety 2019 | molluscs2017–2018Basis not stated | not detected. | ||
1 finding · 1 study | ||||
| Oysters, as soldUc-Peraza et al. 2022 | five Yucatán fishing sites pooled2018Dry weight | mean. | ||
22 findings · 1 study | ||||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S1 Dandong2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S2 Dalian2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S3 Tangshan2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S4 Yantai2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S5 Weihai2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S6 Qingdao2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S7 Lianyungang2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS1 (Table 1 row 1)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS1 (Table 1 row 3)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS2 (Table 1 row 2)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS2 (Table 1 row 4)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS3 (Table 1 row 5)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS4 (Table 1 row 6)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS5 (Table 1 row 7)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS6 (Table 1 row 8)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S8 Ningbo2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S9 Wenzhou2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S10 Quanzhou2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S11 Xiamen2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S12 Chaozhou2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S13 Shenzhen2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S14 Beihai2014–2015Dry weight | mean. | ||
1 finding · 1 study | ||||
| Oysters, as soldUc-Peraza et al. 2022 | five Yucatán fishing sites pooled2018Dry weight | mean. | ||
22 findings · 1 study | ||||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S1 Dandong2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S2 Dalian2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S3 Tangshan2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S4 Yantai2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S5 Weihai2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S6 Qingdao2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S7 Lianyungang2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS1 (Table 1 row 1)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS1 (Table 1 row 3)2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS2 (Table 1 row 2)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS2 (Table 1 row 4)2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS3 (Table 1 row 5)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS4 (Table 1 row 6)2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS5 (Table 1 row 7)2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS6 (Table 1 row 8)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S8 Ningbo2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S9 Wenzhou2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S10 Quanzhou2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S11 Xiamen2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S12 Chaozhou2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S13 Shenzhen2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S14 Beihai2014–2015Dry weight | mean. | ||
1 finding · 1 study | ||||
| Oysters, as soldUc-Peraza et al. 2022 | five Yucatán fishing sites pooled2018Dry weight | not detected. | ||
22 findings · 1 study | ||||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S1 Dandong2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S2 Dalian2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S3 Tangshan2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S4 Yantai2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S5 Weihai2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S6 Qingdao2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S7 Lianyungang2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS1 (Table 1 row 1)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS1 (Table 1 row 3)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS2 (Table 1 row 2)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS2 (Table 1 row 4)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS3 (Table 1 row 5)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS4 (Table 1 row 6)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS5 (Table 1 row 7)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS6 (Table 1 row 8)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S8 Ningbo2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S9 Wenzhou2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S10 Quanzhou2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S11 Xiamen2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S12 Chaozhou2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S13 Shenzhen2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S14 Beihai2014–2015Dry weight | mean. | ||
1 finding · 1 study | ||||
| Oysters, as soldCentre for Food Safety 2019 | molluscs2017–2018Basis not stated | mean. | ||
22 findings · 1 study | ||||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S1 Dandong2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S2 Dalian2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S3 Tangshan2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S4 Yantai2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S5 Weihai2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S6 Qingdao2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S7 Lianyungang2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS1 (Table 1 row 1)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS1 (Table 1 row 3)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS2 (Table 1 row 2)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS2 (Table 1 row 4)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS3 (Table 1 row 5)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS4 (Table 1 row 6)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS5 (Table 1 row 7)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS6 (Table 1 row 8)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S8 Ningbo2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S9 Wenzhou2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S10 Quanzhou2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S11 Xiamen2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S12 Chaozhou2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S13 Shenzhen2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S14 Beihai2014–2015Dry weight | mean. | ||
1 finding · 1 study | ||||
| Oysters, as soldUc-Peraza et al. 2022 | five Yucatán fishing sites pooled2018Dry weight | mean. | ||
3 findings · 2 studies | ||||
| Oysters, as soldChung et al. 2020 | all samples2017–2018As sold / fresh | mean. | ||
| Oysters, as soldUc-Peraza et al. 2022 | five Yucatán fishing sites pooled2018As sold / fresh | mean. | ||
| Oysters, as soldUc-Peraza et al. 2022 | five Yucatán fishing sites pooled2018Dry weight | mean. | ||
1 finding · 1 study | ||||
| Oysters, as soldUc-Peraza et al. 2022 | five Yucatán fishing sites pooled2018Dry weight | mean. | ||
3 findings · 3 studies | ||||
| Oysters, as soldChung et al. 2020 | all samples2017–2018As sold / fresh | mean. | ||
| Oysters, as soldUc-Peraza et al. 2022 | five Yucatán fishing sites pooled2018Dry weight | mean. | ||
| Oysters, as soldCentre for Food Safety 2019 | molluscs2017–2018Basis not stated | mean. | ||
22 findings · 1 study | ||||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S1 Dandong2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S2 Dalian2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S3 Tangshan2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S4 Yantai2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S5 Weihai2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S6 Qingdao2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S7 Lianyungang2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS1 (Table 1 row 1)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS1 (Table 1 row 3)2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS2 (Table 1 row 2)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS2 (Table 1 row 4)2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS3 (Table 1 row 5)2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS4 (Table 1 row 6)2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS5 (Table 1 row 7)2014–2015Dry weight | not detected. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS6 (Table 1 row 8)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S8 Ningbo2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S9 Wenzhou2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S10 Quanzhou2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S11 Xiamen2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S12 Chaozhou2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S13 Shenzhen2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S14 Beihai2014–2015Dry weight | mean. | ||
1 finding · 1 study | ||||
| Oysters, as soldUc-Peraza et al. 2022 | five Yucatán fishing sites pooled2018As sold / fresh | mean. | ||
2 findings · 1 study | ||||
| Oysters, as soldKaise et al. 1988 | lipid-soluble1987Basis not stated | sample value. | ||
| Oysters, as soldKaise et al. 1988 | water-soluble1987Basis not stated | sample value. | ||
2 findings · 2 studies | ||||
| Oysters, as soldChung et al. 2020 | all samples2017–2018As sold / fresh | mean. | ||
| Oysters, as soldUc-Peraza et al. 2022 | five Yucatán fishing sites pooled2018Dry weight | not detected. | ||
22 findings · 1 study | ||||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S1 Dandong2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S2 Dalian2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S3 Tangshan2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S4 Yantai2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S5 Weihai2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S6 Qingdao2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Northern coastal zone, S7 Lianyungang2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS1 (Table 1 row 1)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS1 (Table 1 row 3)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS2 (Table 1 row 2)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS2 (Table 1 row 4)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS3 (Table 1 row 5)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS4 (Table 1 row 6)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS5 (Table 1 row 7)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Shanghai seafood market SHS6 (Table 1 row 8)2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S8 Ningbo2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S9 Wenzhou2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S10 Quanzhou2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S11 Xiamen2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S12 Chaozhou2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S13 Shenzhen2014–2015Dry weight | mean. | ||
| Oysters, as soldChen et al. 2019 | Southern coastal zone, S14 Beihai2014–2015Dry weight | mean. | ||
1 finding · 1 study | ||||
| Oysters, as soldCentre for Food Safety 2019 | molluscs2017–2018Basis not stated | 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 oysters Pb reference · Oysters, as sold
Reference and scope
HMI oysters Pb reference · Oysters, as sold. Oysters, 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 | 35–100 (bounded) | 100–103 (bounded) | 103 |
| Alternative weighting | 35–100 (bounded) | 100–103 (bounded) | 103 |
67 reference units; 3 sampling families. Counts describe evidence units, not independent studies or certainty.
| Contributing family | Reference units | Weight |
|---|---|---|
| WHO GEMS/Food | 52 | 33% |
| Piras et al. 2013 | 1 | 33% |
| Valencia et al. 2021 | 14 | 33% |
Methods
HMI pools subgroup medians for oysters, 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 to 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:oyster-15171c57ccf5:28322215ff46
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 oysters Cd reference · Oysters, as sold
Reference and scope
HMI oysters Cd reference · Oysters, as sold. Oysters, 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 | 90 | 120 | 235 |
| Alternative weighting | 90 | 120 | 235 |
51 reference units; 4 sampling families. Counts describe evidence units, not independent studies or certainty.
| Contributing family | Reference units | Weight |
|---|---|---|
| WHO GEMS/Food | 37 | 25% |
| EFSA Panel on Contaminants in the Food Chain (CONTAM) 2009 | 1 | 25% |
| Piras et al. 2013 | 1 | 25% |
| Valencia et al. 2021 | 12 | 25% |
Methods
HMI pools subgroup medians for oysters, 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 to Q3 spread are required. This is a display eligibility rule, not statistical validation.
Limitations
4 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
- WHO GEMS/Food
- EFSA Panel on Contaminants in the Food Chain (CONTAM) 2009
- Piras et al. 2013
- Valencia et al. 2021
Reference version and interpretation
Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.
hmi-pooled-reference-v2:oyster-9d3d5dc1d3ad:cfc2c73f34db
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 oysters tAs reference · Oysters, as sold
Reference and scope
HMI oysters tAs reference · Oysters, as sold. Oysters, 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 | 2190 | 2710 | 6000 |
| Alternative weighting | 2330 | 2750 | 6100 |
41 reference units; 2 sampling families. Counts describe evidence units, not independent studies or certainty.
| Contributing family | Reference units | Weight |
|---|---|---|
| WHO GEMS/Food | 34 | 50% |
| Shiomi et al. 1988 | 7 | 50% |
Methods
HMI pools subgroup medians for oysters, 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 to 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:oyster-b87c307c2af7:183521e9dff1
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 oysters iAs reference · Oysters, as sold
Reference and scope
HMI oysters iAs reference · Oysters, as sold. Oysters, 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 | ≤11 | 10.8–20 (bounded) |
| Alternative weighting | ≤11 | ≤11 | 10.3–20 (bounded) |
33 reference units; 2 sampling families. Counts describe evidence units, not independent studies or certainty.
| Contributing family | Reference units | Weight |
|---|---|---|
| WHO GEMS/Food | 32 | 50% |
| Matsumoto-Tanibuchi et al. 2019 | 1 | 50% |
Methods
HMI pools subgroup medians for oysters, 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 to 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:oyster-02068ea9a3b8:99b49a5cc84e
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 oysters iAs reference · Oysters, as sold, dry weight
Reference and scope
HMI oysters iAs reference · Oysters, as sold, dry weight. Oysters, as sold; Dry weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.
| Reference (µg/kg) | Q1 | Median | Q3 |
|---|---|---|---|
| Primary HMI reference | 3.69 | 3.69 | 3.69 |
| Alternative weighting | 3.69 | 3.69 | 3.69 |
1 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.
| Contributing family | Reference units | Weight |
|---|---|---|
| WHO GEMS/Food | 1 | 100% |
Methods
HMI pools subgroup medians for oysters, 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 to Q3 spread are required. This is a display eligibility rule, not statistical validation.
Limitations
WHO GEMS/Food is the only compatible sampling family for oysters, as sold on this basis in the completed oysters 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
Reference version and interpretation
Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.
hmi-pooled-reference-v2:oyster-5429316be8eb:56b8a501a603
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 oysters DMA reference · Oysters, as sold
Reference and scope
HMI oysters DMA reference · Oysters, as sold. Oysters, 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 | 0.098 | 0.098 | 0.098 |
| Alternative weighting | 0.098 | 0.098 | 0.098 |
1 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.
| Contributing family | Reference units | Weight |
|---|---|---|
| WHO GEMS/Food | 1 | 100% |
Methods
HMI pools subgroup medians for oysters, 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 to Q3 spread are required. This is a display eligibility rule, not statistical validation.
Limitations
WHO GEMS/Food is the only compatible sampling family for oysters, as sold on this basis in the completed oysters 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
Reference version and interpretation
Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.
hmi-pooled-reference-v2:oyster-d80244b559bc:42588e1fb69f
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 oysters tHg reference · Oysters, as sold
Reference and scope
HMI oysters tHg reference · Oysters, as sold. Oysters, 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 | 11–21 (bounded) | 11–500 (bounded) |
| Alternative weighting | ≤11 | 11–24 (bounded) | 11.3–500 (bounded) |
48 reference units; 3 sampling families. Counts describe evidence units, not independent studies or certainty.
| Contributing family | Reference units | Weight |
|---|---|---|
| WHO GEMS/Food | 46 | 33% |
| Lehel et al. 2018 | 1 | 33% |
| Piras et al. 2013 | 1 | 33% |
Methods
HMI pools subgroup medians for oysters, 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 to 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:oyster-6d20a282693e:8b003080e3bf
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 oysters MeHg reference · Oysters, as sold
Reference and scope
HMI oysters MeHg reference · Oysters, as sold. Oysters, 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 | ≤14 | ≤14 | ≤14 |
| Alternative weighting | ≤14 | ≤14 | ≤14 |
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 oysters, 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 to Q3 spread are required. This is a display eligibility rule, not statistical validation.
Limitations
WHO GEMS/Food is the only compatible sampling family for oysters, as sold on this basis in the completed oysters 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
Reference version and interpretation
Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.
hmi-pooled-reference-v2:oyster-2e64c9a2826b:f87b0bfcafdc
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 oysters Al reference · Oysters, as sold
Reference and scope
HMI oysters Al reference · Oysters, as sold. Oysters, 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 | 4440 | 6750 | 9060 |
| Alternative weighting | 4440 | 6750 | 9060 |
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 oysters, 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 to Q3 spread are required. This is a display eligibility rule, not statistical validation.
Limitations
WHO GEMS/Food is the only compatible sampling family for oysters, as sold on this basis in the completed oysters 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
Reference version and interpretation
Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.
hmi-pooled-reference-v2:oyster-629cf87785ea:26c082568282
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 oysters Sn reference · Oysters, as sold
Reference and scope
HMI oysters Sn reference · Oysters, as sold. Oysters, 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 | 18.9 | 26.1 | 41 |
| Alternative weighting | 18.9 | 26.1 | 111 |
5 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.
| Contributing family | Reference units | Weight |
|---|---|---|
| WHO GEMS/Food | 5 | 100% |
Methods
HMI pools subgroup medians for oysters, 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 to Q3 spread are required. This is a display eligibility rule, not statistical validation.
Limitations
WHO GEMS/Food is the only compatible sampling family for oysters, as sold on this basis in the completed oysters 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
Reference version and interpretation
Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.
hmi-pooled-reference-v2:oyster-42616c0a606e:53ae9faed78d
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 oysters Cu reference · Oysters, as sold
Reference and scope
HMI oysters Cu reference · Oysters, as sold. Oysters, 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 | ≤32 | ≤32 | ≤32 |
| Alternative weighting | ≤32 | ≤32 | ≤32 |
1 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.
| Contributing family | Reference units | Weight |
|---|---|---|
| Martin et al. 2017 | 1 | 100% |
Methods
HMI pools subgroup medians for oysters, 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 to Q3 spread are required. This is a display eligibility rule, not statistical validation.
Limitations
Martin et al. 2017 is the only compatible sampling family for oysters, as sold on this basis in the completed oysters 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
Reference version and interpretation
Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.
hmi-pooled-reference-v2:oyster-2493d66d73fb:7df8a61271ae
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 oysters Cu reference · Oysters, as sold, dry weight
Reference and scope
HMI oysters Cu reference · Oysters, as sold, dry weight. Oysters, as sold; Dry weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.
| Reference (µg/kg) | Q1 | Median | Q3 |
|---|---|---|---|
| Primary HMI reference | ≤32 | ≤32 | ≤32 |
| Alternative weighting | ≤32 | ≤32 | ≤32 |
1 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.
| Contributing family | Reference units | Weight |
|---|---|---|
| Martin et al. 2017 | 1 | 100% |
Methods
HMI pools subgroup medians for oysters, 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 to Q3 spread are required. This is a display eligibility rule, not statistical validation.
Limitations
Martin et al. 2017 is the only compatible sampling family for oysters, as sold on this basis in the completed oysters 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
Reference version and interpretation
Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.
hmi-pooled-reference-v2:oyster-93e586fc4832:19d485d396fb
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 oysters DBT_as_Sn reference · Oysters, as sold, dry weight
Reference and scope
HMI oysters DBT_as_Sn reference · Oysters, as sold, dry weight. Oysters, as sold; Dry 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 |
12 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.
| Contributing family | Reference units | Weight |
|---|---|---|
| Chen et al. 2019 | 12 | 100% |
Methods
HMI pools subgroup medians for oysters, 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 to Q3 spread are required. This is a display eligibility rule, not statistical validation.
Limitations
Chen et al. 2019 is the only compatible sampling family for oysters, as sold on this basis in the completed oysters 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
Reference version and interpretation
Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.
hmi-pooled-reference-v2:oyster-c6deae07e58b:628bf40d1f1f
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 oysters DOT reference · Oysters, as sold
Reference and scope
HMI oysters DOT reference · Oysters, as sold. Oysters, 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 | ≤0.25 | ≤0.25 | ≤0.25 |
| Alternative weighting | ≤0.25 | ≤0.25 | ≤0.25 |
1 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.
| Contributing family | Reference units | Weight |
|---|---|---|
| Chung et al. 2020 | 1 | 100% |
Methods
HMI pools subgroup medians for oysters, 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 to Q3 spread are required. This is a display eligibility rule, not statistical validation.
Limitations
Chung et al. 2020 is the only compatible sampling family for oysters, as sold on this basis in the completed oysters 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
Reference version and interpretation
Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.
hmi-pooled-reference-v2:oyster-759d7069817c:eba07bb76522
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 oysters MBT_as_Sn reference · Oysters, as sold, dry weight
Reference and scope
HMI oysters MBT_as_Sn reference · Oysters, as sold, dry weight. Oysters, as sold; Dry 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 |
13 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.
| Contributing family | Reference units | Weight |
|---|---|---|
| Chen et al. 2019 | 13 | 100% |
Methods
HMI pools subgroup medians for oysters, 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 to Q3 spread are required. This is a display eligibility rule, not statistical validation.
Limitations
Chen et al. 2019 is the only compatible sampling family for oysters, as sold on this basis in the completed oysters 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
Reference version and interpretation
Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.
hmi-pooled-reference-v2:oyster-ae7b8d367c75:545d39ae35c7
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 oysters MPhT reference · Oysters, as sold, dry weight
Reference and scope
HMI oysters MPhT reference · Oysters, as sold, dry weight. Oysters, as sold; Dry weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.
| Reference (µg/kg) | Q1 | Median | Q3 |
|---|---|---|---|
| Primary HMI reference | ≤3.3 | ≤3.3 | ≤3.3 |
| Alternative weighting | ≤3.3 | ≤3.3 | ≤3.3 |
1 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.
| Contributing family | Reference units | Weight |
|---|---|---|
| Uc-Peraza et al. 2022 | 1 | 100% |
Methods
HMI pools subgroup medians for oysters, 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 to Q3 spread are required. This is a display eligibility rule, not statistical validation.
Limitations
Uc-Peraza et al. 2022 is the only compatible sampling family for oysters, as sold on this basis in the completed oysters 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
Reference version and interpretation
Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.
hmi-pooled-reference-v2:oyster-16ad20ca6889:662b640a1e08
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 oysters MPhT_as_Sn reference · Oysters, as sold, dry weight
Reference and scope
HMI oysters MPhT_as_Sn reference · Oysters, as sold, dry weight. Oysters, as sold; Dry 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 |
3 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.
| Contributing family | Reference units | Weight |
|---|---|---|
| Chen et al. 2019 | 3 | 100% |
Methods
HMI pools subgroup medians for oysters, 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 to Q3 spread are required. This is a display eligibility rule, not statistical validation.
Limitations
Chen et al. 2019 is the only compatible sampling family for oysters, as sold on this basis in the completed oysters 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
Reference version and interpretation
Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.
hmi-pooled-reference-v2:oyster-ad2aca8f7803:6c7e808256f0
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 oysters TBT_as_Sn reference · Oysters, as sold, dry weight
Reference and scope
HMI oysters TBT_as_Sn reference · Oysters, as sold, dry weight. Oysters, as sold; Dry 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 |
8 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.
| Contributing family | Reference units | Weight |
|---|---|---|
| Chen et al. 2019 | 8 | 100% |
Methods
HMI pools subgroup medians for oysters, 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 to Q3 spread are required. This is a display eligibility rule, not statistical validation.
Limitations
Chen et al. 2019 is the only compatible sampling family for oysters, as sold on this basis in the completed oysters 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
Reference version and interpretation
Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.
hmi-pooled-reference-v2:oyster-0d225aaa3586:756b12ee1e6f
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 oysters TPhT reference · Oysters, as sold, dry weight
Reference and scope
HMI oysters TPhT reference · Oysters, as sold, dry weight. Oysters, as sold; Dry weight, µg/kg; no moisture conversion. Distribution of subgroup median concentration values.
| Reference (µg/kg) | Q1 | Median | Q3 |
|---|---|---|---|
| Primary HMI reference | ≤3.3 | ≤3.3 | ≤3.3 |
| Alternative weighting | ≤3.3 | ≤3.3 | ≤3.3 |
1 reference units; 1 sampling family. Counts describe evidence units, not independent studies or certainty.
| Contributing family | Reference units | Weight |
|---|---|---|
| Uc-Peraza et al. 2022 | 1 | 100% |
Methods
HMI pools subgroup medians for oysters, 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 to Q3 spread are required. This is a display eligibility rule, not statistical validation.
Limitations
Uc-Peraza et al. 2022 is the only compatible sampling family for oysters, as sold on this basis in the completed oysters 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
Reference version and interpretation
Frozen evidence selection: 2026-10-22. Method: hmi-pooled-reference-v2.
hmi-pooled-reference-v2:oyster-87a2fee2c4da:0e82a24cef55
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.
The source reports only a percentile, range or maximum for these samples, with no mean or median to place against the reference. Spread figures that do have a mean or median are shown on that row instead.
The value could not be reconciled with its own paper, so it is shown but not compared.
The result is below a reporting limit, and the range from zero to that limit crosses more than one band.
No medians or sample values exist for this form and metal, so no HMI reference could be built.
The HMI reference for this form has fewer than four units or no measurable spread, below the display minimum.
The result is on a basis (dry weight, or not stated) that no HMI reference for this form uses, so it cannot be placed.
No findings match these filters. Change the selection or reset to show all source findings.
How metals reach oysters
The evidence on how metals reach oysters comes from studies that compared exposed and ordinary settings. Oysters, as sold from water-soluble had TMA higher at 6,150 µg/kg, against 430 µg/kg for lipid-soluble in the same study.7Distribution of inorganic arsenic and methylated arsenic in marine organismsApplied Organometallic ChemistryRead source →
These are observational comparisons from single studies; the size of the difference depends on the site, metal and distance.
Which forms and regions measured lower
The HMI reference for lead in oysters, as sold pools 67 subgroup units from 3 sampling families, with a median of between 100 and 103 µg/kg and a middle half spanning between 35 and 100 (lower quartile) and 103 µg/kg (upper quartile).1GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →6Lead and other heavy metals (cadmium and mercury) accumulation in bivalve mollusks (Mytilus galloprovincialis, Ruditapes spp. and Crassostrea gigas) sampled in Sardinia in 2008-2012Italian Journal of Food Safety 2013; 2:e49 (pp. 182-187)Read source →9Heavy metal accumulation and risk assessment of lead and cadmium in cultured oysters (Crassostrea iredalei) of Cañacao Bay, PhilippinesSustinere: Journal of Environment and Sustainability 5(2), 64-78Read source → For cadmium in oysters, as sold, the reference median was 120 µg/kg, with a middle half from 90 to 235 µg/kg across 51 units.1GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →6Lead and other heavy metals (cadmium and mercury) accumulation in bivalve mollusks (Mytilus galloprovincialis, Ruditapes spp. and Crassostrea gigas) sampled in Sardinia in 2008-2012Italian Journal of Food Safety 2013; 2:e49 (pp. 182-187)Read source →9Heavy metal accumulation and risk assessment of lead and cadmium in cultured oysters (Crassostrea iredalei) of Cañacao Bay, PhilippinesSustinere: Journal of Environment and Sustainability 5(2), 64-78Read source →12Scientific Opinion of the Panel on Contaminants in the Food Chain on a request from the European Commission on cadmium in foodThe EFSA JournalRead source → For total arsenic in oysters, as sold, the reference median was 2,710 µg/kg, with a middle half from 2,190 to 6,000 µg/kg across 41 units.1GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →13Arsenic Concentrations in Various Tissues of Bivalves and Arsenic Species in GillsNippon Suisan Gakkaishi 54(3): 539 (1988)Read source →
Among GEMS/Food reporting regions, oysters, as sold had the lowest lead subgroup median in WPRO (13 µg/kg) and the highest in WPRO (205 µg/kg); reporting regions are markets, not growing areas.1GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source → For cadmium, the lowest regional median was in WPRO (29.5 µg/kg) and the highest in WPRO (1,200 µg/kg).1GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source → For total arsenic, the lowest regional median was in EURO (1,810 µg/kg) and the highest in WPRO (2,440 µg/kg).1GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →
Targeted oysters, as sold samples in WPRO had lead lower at 115 µg/kg, against 130 µg/kg for WPRO in the same study.1GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source → In another study, targeted oysters, as sold samples in EURO had cadmium lower at 140 µg/kg, against 760 µg/kg for EURO in the same study.1GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →
In one study, lead across 22 groups of oysters ranged from 550 µg/kg (March 2011) to 4,600 µg/kg (October 2011); the lowest is the lowest observed in that study, not an established sourcing preference.4Heavy-metal contents in oysters (Crassostrea gigas) cultivated on the southeastern coast of the Gulf of California, MexicoHidrobiologicaRead source → In another study, cadmium across 4 groups of oysters ranged from 27 µg/kg (Mean of 3 stations, January) to 83 µg/kg (Mean of 3 stations, October); the lowest is the lowest observed in that study, not an established sourcing preference.9Heavy metal accumulation and risk assessment of lead and cadmium in cultured oysters (Crassostrea iredalei) of Cañacao Bay, PhilippinesSustinere: Journal of Environment and Sustainability 5(2), 64-78Read source →
Processing, cooking and preparation
No processing study for metals in this food is in the library yet.
Mitigation for oysters
Lot testing against the applicable limit is the check that can be verified.
No measured way to lower metals in this food is in the library yet.
Trade-offs and limits of controls
Avoiding exposed growing areas lowered the metal measured in the studies available, but no study measured the cost or supply effect of doing so.7Distribution of inorganic arsenic and methylated arsenic in marine organismsApplied Organometallic ChemistryRead source → 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 oysters for metals
Results depend on the method and its reporting limit. Reporting limits for lead ranged from 1.1 µg/kg (Singhato et al. 2025) to 300 µg/kg (WHO GEMS/Food), so a non-detect from a less sensitive method says much less.1GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →8Risk Assessment of Toxic Heavy Metal Exposure in Selected Seafood Species from ThailandFoodsRead source → Reporting limits for cadmium ranged from 0.7 µg/kg (WHO GEMS/Food) to 322 µg/kg (WHO GEMS/Food), so a non-detect from a less sensitive method says much less.1GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source → Reporting limits for total arsenic ranged from 0.7 µg/kg (Singhato et al. 2025) to 1,360 µg/kg (WHO GEMS/Food), so a non-detect from a less sensitive method says much less.1GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →8Risk Assessment of Toxic Heavy Metal Exposure in Selected Seafood Species from ThailandFoodsRead source →
A useful lot result names the form, the basis and a quantification limit well below the limit that applies.
Buying and verifying oysters
No maximum level for metals in oysters was verified from primary text for this page; buyers should confirm the limit that applies in the destination market.
Exposure from oysters
No source in the library converted oysters 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 oysters was decided on its content: 29 occurrence extracted, 29 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.
Oysters FAQs
What heavy metals are found in oysters?
The library reports lead, cadmium, total arsenic, inorganic arsenic, dimethylarsinic acid, monomethylarsonic acid, total mercury, methylmercury, nickel, chromium, aluminium, tin, antimony, Cu, Zn, V, Se, AsB, AsC, AsIII, AsV, DBT, DBT_as_Sn, DOT, DPhT, DPhT_as_Sn, MBT, MBT_as_Sn, MPhT, MPhT_as_Sn, OTC_sum_as_Sn, Sn_total_organotin, sumBT, sumOTC, sumPhT, TBT, TBT_as_Sn, TBT+DBT+TPhT, TMA, TPhT, TPhT_as_Sn and TPT in oysters, most often lead, cadmium and total arsenic.1GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →2Heavy Metals Contamination in Shellfish: Benefit-Risk Evaluation in Central ItalyFoodsRead source →3Heavy metals in seafood purchased from a fishery market in HungaryFood Additives & Contaminants: Part BRead source →4Heavy-metal contents in oysters (Crassostrea gigas) cultivated on the southeastern coast of the Gulf of California, MexicoHidrobiologicaRead source → WHO GEMS/Food submissions reported lead in oysters, as sold from 1,311 results in 3 reporting regions, with subgroup medians from 13 to 205 µg/kg.1GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →
How do heavy metals get into oysters?
In the studies available, oysters from contaminated or exposed settings carried more metal than oysters from the same study’s control.7Distribution of inorganic arsenic and methylated arsenic in marine organismsApplied Organometallic ChemistryRead source → Oysters, as sold from water-soluble had TMA higher at 6,150 µg/kg, against 430 µg/kg for lipid-soluble in the same study.7Distribution of inorganic arsenic and methylated arsenic in marine organismsApplied Organometallic ChemistryRead source →
Which regions report the lowest levels in oysters?
Among GEMS/Food reporting regions, oysters, as sold had the lowest lead subgroup median in WPRO (13 µg/kg) and the highest in WPRO (205 µg/kg); reporting regions are markets, not growing areas.1GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source → For cadmium, the lowest regional median was in WPRO (29.5 µg/kg) and the highest in WPRO (1,200 µg/kg).1GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →
How much of the arsenic in oysters is inorganic?
Inorganic arsenic, the more toxic form, was measured in 20 results from 6 sources, far fewer than total arsenic.1GEMS/Food Contaminants database heavy-metal exportsGEMS/Food Contamination Monitoring and Assessment ProgrammeRead source →7Distribution of inorganic arsenic and methylated arsenic in marine organismsApplied Organometallic ChemistryRead source →14Determination of Inorganic Arsenic in Seaweed and Seafood by LC-ICP-MS: Method ValidationJournal of AOAC InternationalRead source →15The First Hong Kong Total Diet Study: Inorganic ArsenicCentre for Food Safety, Food and Environmental Hygiene Department, Government of the Hong Kong Special Administrative RegionRead source →16Chronic dietary exposure to inorganic arsenicEFSA JournalRead source →17Dietary exposure to inorganic arsenic in the European populationEFSA Journal 2014;12(3):3597Read source → Across 3 other studies of ordinary farms and markets, reported inorganic arsenic means and medians with the basis not stated ranged from 10 µg/kg (EFSA 2021) to 67.3 µg/kg (European Food Safety Authority (EFSA) 2014).16Chronic dietary exposure to inorganic arsenicEFSA JournalRead source →17Dietary exposure to inorganic arsenic in the European populationEFSA Journal 2014;12(3):3597Read 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 exportsDataset
- Heavy Metals Contamination in Shellfish: Benefit-Risk Evaluation in Central ItalyPeer-reviewed
- Heavy metals in seafood purchased from a fishery market in HungaryPeer-reviewed
- Heavy-metal contents in oysters (Crassostrea gigas) cultivated on the southeastern coast of the Gulf of California, MexicoPeer-reviewed
- Heavy metal levels in New Zealand molluscsPeer-reviewed
- Lead and other heavy metals (cadmium and mercury) accumulation in bivalve mollusks (Mytilus galloprovincialis, Ruditapes spp. and Crassostrea gigas) sampled in Sardinia in 2008-2012Peer-reviewed
- Distribution of inorganic arsenic and methylated arsenic in marine organismsPeer-reviewed
- Risk Assessment of Toxic Heavy Metal Exposure in Selected Seafood Species from ThailandPeer-reviewed
- Heavy metal accumulation and risk assessment of lead and cadmium in cultured oysters (Crassostrea iredalei) of Cañacao Bay, PhilippinesPeer-reviewed
- Studies on seasonal pollution of heavy metals in water, sediment, fish and oyster from the Meiliang Bay of Taihu Lake in ChinaPeer-reviewed
- Organotin contamination in commercial and wild oysters from China: Increasing occurrence of triphenyltinPeer-reviewed
- Scientific Opinion of the Panel on Contaminants in the Food Chain on a request from the European Commission on cadmium in foodGovernment
- Arsenic Concentrations in Various Tissues of Bivalves and Arsenic Species in GillsPeer-reviewed
- Determination of Inorganic Arsenic in Seaweed and Seafood by LC-ICP-MS: Method ValidationPeer-reviewed
- The First Hong Kong Total Diet Study: Inorganic ArsenicGovernment
- Chronic dietary exposure to inorganic arsenicGovernment
- Dietary exposure to inorganic arsenic in the European populationGovernment
Sources
Browse Oysters 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 oysters record in the library: 29 occurrence sources, references by form and basis, same-study contrasts.