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 Salt (table, sea, Himalayan)’s own as-sold 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-sold basis. 5 of 11 analytes carry a firm ceiling; the remaining 6 are governed by mandatory control or the total-metal screen with no standalone number, itemised in the derivation below. A brand meeting every firm value on a like-for-like basis, and passing every control, qualifies for the mark.
| Analyte | Tier | HMTc limit | Binding basis |
|---|---|---|---|
| Lead (Pb) | Tier 1 | 1000 | strictest government ML, set by product form (see derivation) |
| Cadmium (Cd) | Tier 1 | 500 | strictest government ML (GSO) |
| Total arsenic (tAs) | Tier 2 | 500 | strictest government ML (EU) |
| Inorganic arsenic (iAs) | Tier 1 | 500 | strictest government ML (Israel) |
| Mercury, total (tHg) | Tier 1 | 100 | strictest government ML (EU) |
| Methylmercury (MeHg) | Tier 1 | n/m | not material: controlled analyte (see note) |
| Nickel (Ni) | Tier 2 | control | mandatory control: no government ML; screened every lot (see note) |
| Tin (Sn) | Tier 2 | n/m | not material: controlled analyte (see note) |
| Aluminium (Al) | Tier 2 | n/m | not material: controlled analyte (see note) |
| Total chromium (Cr) | Tier 2 | control | mandatory control: no government ML; screened every lot (see note) |
| Hexavalent chromium (Cr-VI) | Tier 2 | n/m | not material: controlled analyte (see note) |
Tier 1 (Pb, iAs, Hg, MeHg, Cd) are zero-tolerance toxics with no established safe threshold. Tier 2 (tAs, Ni, Sn, Al, Cr, Cr-VI) are held to the same government limit: tiering sets how the program reacts to an exceedance, not any permission to exceed it. A product is certified only when every analyte is at or below 100% of its published limit; above the limit, on any metal, it is not certified and carries no mark.
Derivation
For Salt (table, sea, Himalayan), each HMTc limit is the strictest maximum level any credible government sets for the product, named in the Binding column with the count of jurisdictions that concur at that value. Where no government regulates the analyte, the cell is a mandatory control or a not-material determination, never an invented number.
| Analyte | HMTc | Binding | Basis |
|---|---|---|---|
| Lead (Pb) | 1000 | by product form (below) | sovereign ML, form-specific |
| Cadmium (Cd) | 500 | GSO · +2 concurring | direct sovereign ML |
| Total arsenic (tAs) | 500 | EU · +1 concurring | direct sovereign ML |
| Inorganic arsenic (iAs) | 500 | Israel | direct sovereign ML |
| Mercury, total (tHg) | 100 | EU · +1 concurring | direct sovereign ML |
| Methylmercury (MeHg) | n/m | ≤ tHg | not material in this matrix |
| Nickel (Ni) | control | screened every lot | mandatory control: no government ML |
| Tin (Sn) | n/m | controlled | not material in this matrix |
| Aluminium (Al) | n/m | controlled | not material in this matrix |
| Total chromium (Cr) | control | screened every lot | mandatory control: no government ML |
| Hexavalent chromium (Cr-VI) | n/m | ≤ Cr | not material in this matrix |
Form-specific limits
Where a government sets the maximum by product sub-form, the HMTc column above shows the range and the exact ceiling for each form is listed here. A certified product meets the ceiling for its own form.
| Product form | HMTc (µg/kg) | Binding jurisdiction |
|---|---|---|
| refined / general food-grade salt (table salt) | 1000 | EU |
| unrefined salt (fleur de sel, grey salt, manually harvested sea salt) | 1000 | China |
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.
3 studies in the certified-market pool measured lead in Salt across 20 certified-market samples. The pooled distribution centres on a median of 244 ppb and reaches 7.7 mg/kg at the 95th percentile. Samsiyah 2019, Salaheldin 2025, Wu 2021.
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 7.7 mg/kg, at or above the government ceiling of 1 mg/kg, so the government maximum binds. Why lead is limited →
2 studies in the certified-market pool measured cadmium in Salt across 5 certified-market samples. The pooled distribution centres on a median of 9.4 ppb and reaches 16 ppb at the 95th percentile. Salaheldin 2025, Wu 2021.
HMTc sets 500 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 16 ppb (provisional), against a government ceiling of 500 ppb. Why cadmium is limited →
1 study in the certified-market pool measured total arsenic in Salt across 4 certified-market samples. The pooled distribution centres on a median of 7.8 ppb and reaches 8.9 ppb at the 95th percentile. Salaheldin 2025.
HMTc sets 500 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 9 ppb, against a government ceiling of 500 ppb. Why total arsenic is limited →
No citable primary occurrence measurement is routed to this cell in the corpus.
HMTc sets no standalone aluminium limit for Salt. Aluminium in salt derives from permitted anti-caking additives, not contamination. In the US, sodium aluminosilicate is GRAS as an anti-caking agent in table salt up to 2% (21 CFR 182.2727). In the EU most aluminium-silicate anti-caking additives were removed for consumer protection by Reg (EU) 380/2012 (E556/E558/E559 banned from 2014; E554/E555 restricted to non-salt uses), so EU table salt carries little additive Al. Dietary aluminium is managed by intake against the EFSA TWI (1 mg/kg bw/week) and JECFA PTWI (2 mg/kg bw/week) with additive use-level controls, not by per-food contaminant MLs; oral bioavailability from food is ~0.1-0.3%. No credible regulator sets an aluminium contaminant ML for salt. The single pooled datum (n=1, 164 mg/kg) cannot distinguish additive from natural background. The analyte is controlled by Managed by additive law + TWI; periodic screen, not a standalone number. Why aluminium is limited →
Risk Flag
On the published occurrence literature to date, Salt (table, sea, Himalayan) 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). Salt (table, sea, Himalayan): HMTc standard. Institute of Contaminant Standards.
© 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.