How limits are set
The standard for each analyte is the strictest maximum level set by any credible government regulator — among them the European Union, Codex Alimentarius, the US FDA, Australia/New Zealand, the Gulf states (GSO), and the national authorities of every jurisdiction that regulates the product — converted into Marine non-predatory fish (sardine, anchovy, salmon, cod, herring, mackerel)’s own as-consumed basis. It is a lookup of sovereign law, carrying at most one disclosed basis conversion where the law is written in another basis, and an explicit read-across where no government regulates the exact product. A certified product sits at or below every applicable sovereign limit at once.
Where no government regulates the exact product for an analyte, the standard does not go blank or invent a number: the limit is read across from the nearest government value for an analogous product, so a certified product still sits at or below a real sovereign limit. The ratchet tightens these after publication as surveillance warrants.
Master Limit Table
All values in ppb (µg/kg), as-consumed basis. 10 of 11 analytes carry a firm ceiling; the remaining 1 are toxic species bounded by their parent totals (species ≤ total, measured on every lot), so every analyte carries an enforceable ceiling. A brand meeting every value on a like-for-like basis qualifies for the mark.
| Analyte | HMTc limit | Binding basis |
|---|---|---|
| Lead (Pb) | 200 | strictest government ML (Fiji) |
| Inorganic arsenic (iAs) | 100 | strictest government ML (EU) |
| Total arsenic (tAs) | 1000 | strictest government ML (Paraguay) |
| Mercury, total (tHg) | 300 | strictest government ML (EU) |
| Methylmercury (MeHg) | bounded | ≤ total tHg, measured every lot (see note) |
| Cadmium (Cd) | 50 | strictest government ML (GSO) |
| Nickel (Ni) | 2000 | government read-across (EU) |
| Total chromium (Cr) | 1000 | strictest government ML (Hong Kong) |
| Hexavalent chromium (Cr-VI) | 10 | government read-across (US-CA) |
| Tin (Sn) | 200000 | government read-across (EU) |
| Aluminium (Al) | 100000 | government read-across (China) |
Every claim analyte is equal at the gate. A product is certified only when every analyte is at or below 100% of its published government floor or disclosed read-across; above the limit, on any metal, it is not certified and carries no mark. Mercury is limited in both forms: total mercury (tHg) and methylmercury (MeHg) are separate ceilings that must both be met, set to the species-specific tier each government assigns (predatory fish carry the higher methylmercury ceiling, lower-trophic species the lower; where the total-mercury ceiling is stricter, methylmercury is bounded by it). Total arsenic (tAs) operates as a reflex screen to inorganic-arsenic (iAs) speciation, since most arsenic in seafood is non-toxic organic arsenobetaine. Every panel analyte carries a limit of record; where no government regulates the exact product (nickel, hexavalent chromium, aluminium, and non-canned tin), the ceiling is a disclosed read-across to the nearest applicable sovereign instrument named in the derivation, never an occurrence-derived number. Tin migrates from the can, so for non-canned seafood the read-across is a packaging-migration baseline that clean product clears.
Derivation
The full derivation for Marine non-predatory fish (sardine, anchovy, salmon, cod, herring, mackerel). Each row lists every government maximum level in force worldwide, converted to the as-consumed basis; the HMTc limit is the strictest of them, and the last column names which sovereign law binds. A blank cell means that government sets no limit for this analyte in this product.
| Analyte | EU | AU/NZ | GSO | India | Mercosur | Costa Rica | Fiji | Guyana | Israel | Mexico | Panama | Philippines | Paraguay | Singapore | Thailand | Trinidad & Tobago | Uruguay | Vietnam | Hong Kong | HMTc | Binds |
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Lead (Pb) | 300 | 500 | 300 | 300 | 300 | 300 | 200 | 300 | 300 | 500 | 300 | 300 | 300 | — | 300 | 2000 | — | 300 | 300 | 200 | Fiji |
| Inorganic arsenic (iAs) | 100 | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 100 | 100 | EU |
| Total arsenic (tAs) | — | 2000 | — | 76000 | 1000 | — | — | — | 1000 | — | — | — | 1000 | — | — | — | — | — | — | 1000 | Paraguay |
| Mercury, total (tHg) | 300 | 500 | 1000 | — | 500 | 500 | 500 | 500 | 500 | — | 500 | — | 500 | 500 | — | — | 500 | 500 | — | 300 | EU |
| Methylmercury (MeHg) | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | bounded&sup5; | species ≤ tHg |
| Cadmium (Cd) | — | — | 50 | 300 | 50 | 50 | 50 | 50 | 50 | 500 | 50 | — | 50 | — | 1000 | — | — | 50 | 100 | 50 | GSO |
| Nickel (Ni) | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 2000² | read-across |
| Total chromium (Cr) | — | — | — | 12000 | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 1000 | 1000 | Hong Kong |
| Hexavalent chromium (Cr-VI) | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 10² | read-across |
| Tin (Sn) | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 200000² | read-across |
| Aluminium (Al) | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | — | 100000² | read-across |
All values µg/kg (ppb), as-consumed basis. ² no government regulates this analyte for this exact product form: the value is a disclosed read-across from the nearest applicable government maximum, and the derivation names the instrument it comes from. It is never taken from occurrence data. After publication the standards ratchet may tighten it, using certified-lot results only. ³ not material in this matrix: measured but with no standalone number, controlled by packaging control or by the total-metal screen, not an invented value. &sup5; a toxic species governed by and bounded by its parent total (for example inorganic arsenic ≤ total arsenic): the species can never exceed the total, so the total ceiling is the species ceiling. The total metal is measured on every lot and the species is established at baseline; no separate species ceiling is published. On ongoing lots the species is speciated whenever the total exceeds its limit.
Occurrence and derivation rationale
For each analyte on the panel: what the peer-reviewed and survey literature measured in this category, cited one way to the Heavy Metal Index, and the Method v2.0 reasoning behind the certification limit — including, where no government sets a number, why the program sets one anyway. Occurrence figures are literature findings; the derivation is the certifier's.
1 study in the certified-market pool measured lead in Fish — marine, non-predatory across 207 certified-market samples. The pooled distribution centres on a median of 19 ppb and reaches 673 ppb at the 95th percentile. Singhato 2025.
HMTc sets 200 ppb (regulatory-alignment): the strictest applicable government maximum level for this product form, adopted under Method v2.0 as the default certification standard. The certified-market pool's P97 is 760 ppb, at or above the government ceiling of 200 ppb, so the government maximum binds. Why lead is limited →
3 studies in the certified-market pool measured inorganic arsenic in Fish — marine, non-predatory across 8 certified-market samples. The pooled distribution centres on a median of 72 ppb and reaches 122 ppb at the 95th percentile. Norin 1985, Park 2005, Munoz 1999.
HMTc sets 100 ppb (regulatory-alignment): the strictest applicable government maximum level for this product form, adopted under Method v2.0 as the default certification standard. The certified-market pool's P97 is 122 ppb, at or above the government ceiling of 100 ppb, so the government maximum binds. Why inorganic arsenic is limited →
1 study in the certified-market pool measured total arsenic in Fish — marine, non-predatory across 16 certified-market samples. The pooled distribution centres on a median of 2.8 mg/kg and reaches 78.8 mg/kg at the 95th percentile. Singhato 2025.
HMTc sets 1 mg/kg (regulatory-alignment): the strictest applicable government maximum level for this product form, adopted under Method v2.0 as the default certification standard. The certified-market pool's P97 is 82.6 mg/kg, at or above the government ceiling of 1 mg/kg, so the government maximum binds. Why total arsenic is limited →
4 studies in the certified-market pool measured total mercury in Fish — marine, non-predatory across 909 certified-market samples. The pooled distribution centres on a median of 70 ppb and reaches 467 ppb at the 95th percentile, with a measured maximum of 1.8 mg/kg. Garofalo 2025, Singhato 2025, Brodziak-Dopierala 2023, Helcom 2017.
HMTc sets 300 ppb (regulatory-alignment): the strictest applicable government maximum level for this product form, adopted under Method v2.0 as the default certification standard. The certified-market pool's P97 is 534 ppb, at or above the government ceiling of 300 ppb, so the government maximum binds. Why total mercury is limited →
No citable primary occurrence measurement is routed to this cell in the corpus.
HMTc sets no standalone methylmercury limit for Fish — marine, non-predatory. MeHg is a component of tHg and bounded by it (MeHg <= tHg), so the tHg ceiling is the MeHg ceiling; no separate MeHg number is published. tHg is measured on every lot, and MeHg is speciated only when tHg exceeds its limit. Why methylmercury is limited →
1 study in the certified-market pool measured cadmium in Fish — marine, non-predatory across 15 certified-market samples. The pooled distribution centres on a median of 65 ppb and reaches 274 ppb at the 95th percentile. Singhato 2025.
HMTc sets 50 ppb (regulatory-alignment): the strictest applicable government maximum level for this product form, adopted under Method v2.0 as the default certification standard. The certified-market pool's P97 is 277 ppb (provisional), at or above the government ceiling of 50 ppb, so the government maximum binds. Why cadmium is limited →
1 study in the certified-market pool measured nickel in Fish — marine, non-predatory across 57 certified-market samples. The pooled distribution centres on a median of 286 ppb and reaches 563 ppb at the 95th percentile. Yap-Almutairi 2022.
HMTc sets 2 mg/kg by read-across: No government sets a nickel ML for animal seafood (EU 2024/1987 nickel covers plant foods and seaweed only). Read-across to the nearest whole-food nickel ceiling (EU 2024/1987 husked rice, 2000) that accommodates observed seafood nickel occurrence; clean product passes, grossly nickel-elevated product fails. Why nickel is limited →
10 studies in the corpus measured tin in Marine non-predatory fish (3562 samples reported across those studies): Jiang 2026, Uc-Peraza 2022, Wickramaarachchige 2022, Chung 2020, Lee 2016, Ho 2014, Olmedo 2013, Hu 2006 and 2 more.
HMTc sets 200 mg/kg by read-across: Tin is a can-migration analyte; no government sets a tin ML for non-canned seafood (every seafood tin ML is canned/tinplate-only). Read-across to the EU 2023/915 general canned-food inorganic-tin ML (200000) as a packaging-migration baseline; fresh/frozen fin-fish has no tin source and passes. Canned product is certified under the canned-seafood subcategory. Why tin is limited →
Risk Flag
On the published occurrence literature to date, Marine non-predatory fish (sardine, anchovy, salmon, cod, herring, mackerel) shows no systematic gap between typical market levels and the limit — the limit being the strictest government maximum for the product (Method v2.0). Certification is decided on a product’s own tested result, not on a distribution; an individual lot or supplier can still exceed a limit.
See the cross-category summary of the ingredients that most often struggle.
Cite this standard
Pendergrass, K. (2026). Marine non-predatory fish (sardine, anchovy, salmon, cod, herring, mackerel): HMTc standard (Standard No. 10.83138/hmtc.std.6.fish-marine-non-predatory). Institute of Contaminant Standards. https://doi.org/10.83138/hmtc.std.6.fish-marine-non-predatory
© 2026 Institute of Contaminant Standards / Heavy Metal Certified. All rights reserved.
The literature baseline for every analyte is maintained independently at the Heavy Metal Index. This certification standard applies those findings; the two are kept editorially separate by design.