How every number on this page is set
No government sets a heavy-metal maximum level for a dietary supplement that protects a child. The adult frameworks that exist — sovereign food-supplement limits (lead 1000–10000 µg/kg), USP <2232> elemental-contaminant PDEs computed for an adult consumer, California Proposition 65 warning doses — are written for a 60–70 kg adult. HMTc instead holds every supplement, adult- or child-labelled, to the strictest sovereign infant-and-child-food maximum level for each analyte, because children routinely consume adult supplements (gummies, protein powders, greens, melatonin drops) and body-weight-normalised exposure makes the child the binding safety case.
Every value on this page is therefore a child-protective read-across, disclosed as such: the anchor is a real sovereign infant-food limit, named in the derivation below, applied to supplements as a voluntary over-compliance. The laxer adult floor is disclosed on every analyte and never selects the number. Where no government sets an infant-and-child-food limit for an analyte — total and hexavalent chromium, methylmercury — no number is invented: the analyte is placed under mandatory control with reflex speciation.
Master Limit Table
All values in ppb (µg/kg), as-sold basis. 8 of 11 analytes carry a firm ceiling; the remainder are governed by mandatory control or reflex-speciation screening 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 | 10 | government read-across (AU/NZ) |
| Inorganic arsenic (iAs) | Tier 1 | 10 | government read-across (EU) |
| Total arsenic (tAs) | Tier 2 | 50 | government read-across (India) |
| Mercury, total (tHg) | Tier 1 | 4 | government read-across (Israel) |
| Methylmercury (MeHg) | Tier 1 | control | mandatory control — no government ML; screened every lot (see note) |
| Cadmium (Cd) | Tier 1 | 5 | government read-across (EU) |
| Hexavalent chromium (Cr-VI) | Tier 2 | control | mandatory control — no government ML; screened every lot (see note) |
| Nickel (Ni) | Tier 2 | 100 | government read-across (EU) |
| Tin (Sn) | Tier 2 | 5000 | government read-across (India) |
| Aluminium (Al) | Tier 2 | 500 | government read-across (AU/NZ) |
| Total chromium (Cr) | Tier 2 | control | mandatory control — no government ML; screened every lot (see note) |
Tier 1 (Pb, iAs, Hg, MeHg, Cd) are zero-tolerance toxics with no established safe threshold. Tier 2 (tAs, Cr-VI, Ni, Sn, Al, Cr) carry a 150% transitional allowance under the program’s Status A–E framework.
Derivation — the child anchor, and the adult floor it overrides
No government regulates a dietary supplement to a child-safe heavy-metal level. Each HMTc limit for Ingredient class — protein/collagen powders is read across from the strictest sovereign infant-and-child-food maximum level for the analyte — the child anchor named below — and applied to all supplements as a voluntary over-compliance. The adult floor column discloses the laxer sovereign supplement limit, USP <2232> oral concentration, and California Prop 65 dose that HMTc declines to use. It is shown, and never selected.
| Analyte | Child-protective anchor | HMTc | Adult floor (disclosed, not used) | Basis |
|---|---|---|---|---|
| Lead (Pb) | AU/NZ — infant formula products | 10 | Thailand 1000–10000 · USP <2232> 500 · Prop 65 0.5 µg/day | child-protective read-across |
| Inorganic arsenic (iAs) | EU — infant formulae, follow-on formulae, food for special medical purposes intended for infants and young children, and young-child formulae placed on the market as liquid | 10 | USP <2232> 1500 | child-protective read-across |
| Total arsenic (tAs) | India — Infant Milk substitute and Infant foods | 50 | ASEAN 300–5000 | child-protective read-across |
| Mercury, total (tHg) | Israel — Infant and toddler formulas, ready-to-eat | 4 | GSO 100–500 · USP <2232> 1500 | child-protective read-across |
| Methylmercury (MeHg) | no infant-food ML exists | control | — | mandatory control — screened every lot |
| Cadmium (Cd) | EU — infant formulae, follow-on formulae, food for special medical purposes intended for infants and young children, and young-child formulae placed on the market as liquid and manufactured from cow's milk proteins or cow's milk protein hydrolysates | 5 | Thailand 300–1000 · USP <2232> 500 · Prop 65 4.1 µg/day | child-protective read-across |
| Hexavalent chromium (Cr-VI) | no infant-food ML exists | control | — | mandatory control — screened every lot |
| Nickel (Ni) | EU — infant/young-child formula, liquid | 100 | — | child-protective read-across |
| Tin (Sn) | India — Infant Milk substitute and Infant foods | 5000 | — | child-protective read-across |
| Aluminium (Al) | AU/NZ — infant formula, follow-on formula, and special medical purpose product for infants other than preterm-infant products | 500 | — | child-protective read-across |
| Total chromium (Cr) | no infant-food ML exists | control | — | mandatory control — screened every lot |
Adult floor values in µg/kg unless marked. Supplement ML is the strictest–laxest sovereign food-supplement maximum on the register; USP <2232> is the oral permitted-daily-exposure concentration at a 10 g/day intake; Prop 65 is the California developmental safe-harbour dose. HMTc holds every supplement to the child anchor instead.
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 Ingredient class — protein/collagen powders across 240 certified-market samples. The pooled distribution centres on a median of 764 ppb and reaches 1 mg/kg at the 95th percentile. Cammilleri 2025.
HMTc sets 10 ppb by read-across: Child-protective read-across from the strictest sovereign infant-and-child-food lead maximum (AU-NZ infant formula, 10 µg/kg). Adult supplement floors run 1000-10000 µg/kg (Thailand 1000; GSO/Israel/Vietnam 3000; ASEAN/Singapore 10000) and adult USP <2232> permits 5 µg/day (500 µg/kg at 10 g/day); California's developmental lead MADL is 0.5 µg/day. HMTc holds ALL supplements to 10 µg/kg because children consume adult supplements and lead has no threshold. Why lead is limited →
1 study in the certified-market pool measured cadmium in Ingredient class — protein/collagen powders across 240 certified-market samples. The pooled distribution centres on a median of 0.9 ppb and reaches 4.8 ppb at the 95th percentile. Cammilleri 2025.
HMTc sets 5 ppb by read-across: Child-protective read-across from the strictest sovereign infant-and-child-food cadmium maximum (EU infant formula, 5 µg/kg). Adult supplement floors run 300-1000 µg/kg; adult USP <2232> permits 5 µg/day (500 µg/kg at 10 g/day); California's developmental cadmium MADL is 4.1 µg/day. HMTc holds ALL supplements to 5 µg/kg. Basis disclosure: this EU anchor (source_id eu2023_cd_formula_cow_liquid_5) is set on a ready-to-feed liquid, as-consumed basis and is read across to the as-sold solid supplement WITHOUT a reconstitution adjustment. A reconstituted liquid formula is roughly 6-8x more dilute than the equivalent as-sold powder, so applying the liquid value directly to a solid is an intentional, disclosed over-strictness (the solid cell runs ~6-8x stricter than the equivalent as-sold powder ML), never an accidental wet/dry conflation; no serving-size conversion selects the limit. Why cadmium is limited →
Cite this standard
Pendergrass, K. “Ingredient class — protein/collagen powders.” In Heavy Metal Tested & Certified (HMTc) Dietary Supplements (Human) standard, version 1.0. Institute of Contaminant Standards (ICS), 2026. DOI: registration pending.
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.