How limits are set
CELL RESOLUTION RULE, applied uniformly across all eight rows. (R1) Where a credible sovereign government writes a maximum level for this product form in this row's native basis, the cell is the strictest such value and is tagged regulatory-alignment.
(R2) Where the exact cell is unregulated but a credible sovereign writes a maximum level for the SAME commodity in an adjacent form or basis, the cell is a disclosed read-across from that named row, taken at face value only where face value is the conservative (stricter) direction.
(R3) Where no sovereign instrument reaches the commodity at all, the cell is a CONTROL: testing is mandatory, an escalation rule is published, and no number is invented.
Aluminium is a control in all eight rows because no jurisdiction regulates aluminium as a produce contaminant. Hexavalent chromium is a substantiated not-material determination wherever a total-chromium parent is published for the row and a control wherever it is not; it is never a published number. Methylmercury is a substantiated not-material determination in all eight rows, bounded by the published total-mercury ceiling, because terrestrial produce has no aquatic methylation compartment.
TAXONOMY LUMPING IS DISCLOSED, NOT SILENTLY RESOLVED: several sovereign instruments split classes that this taxonomy carries as a single row (fruiting versus bulb versus brassica versus legume vegetables inside non-root-vegetables; temperate versus tropical roots and tubers inside root-tuber-vegetables; table olives versus pickled cucumbers versus fermented brassicas inside pickled-fermented-vegetables; pome, stone, citrus and berry fruit inside fresh-fruit).
Because one published HMTc value must be met by every product in the row, each such row binds the strictest value applicable to any member, which is materially stricter than law for the looser members.
Every collapsed split is named in that row's scope_note, and the recommended taxonomy splits are recorded as outstanding items rather than resolved by picking a looser residual-class value, which would let HMTc certify a lot that is unlawful in a market of sale.
Master Limit Table
All values in ppb (µg/kg), as-sold basis. 6 of 11 analytes carry a firm ceiling; the remaining 4 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 | HMTc limit | Binding basis |
|---|---|---|
| Lead (Pb) | 50 | strictest government ML (CH) |
| Inorganic arsenic (iAs) | 60 | strictest government ML (Israel) |
| Total arsenic (tAs) | 100 | strictest government ML (Mercosur) |
| Mercury, total (tHg) | 10 | strictest government ML (Hong Kong) |
| Methylmercury (MeHg) | control | mandatory control — no government ML; screened every lot (see note) |
| Cadmium (Cd) | 20 | strictest government ML (CH) |
| Hexavalent chromium (Cr-VI) | n/m | not material — controlled analyte (see note) |
| Nickel (Ni) | 400 | strictest government ML (EU) |
| Tin (Sn) | n/m | not material — controlled analyte (see note) |
| Aluminium (Al) | control | mandatory control — no government ML; screened every lot (see note) |
| Total chromium (Cr) | screen | screening ceiling — Cr(VI) is the binding health control (see note) |
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.
Derivation
The full derivation for Non-root vegetables (fruiting, brassica, bulb, stem and legume vegetables). Each row lists every government maximum level in force worldwide, converted to the as-sold 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 | HMTc | Binds |
|---|---|---|
| Lead (Pb) | 50 | CH |
| Inorganic arsenic (iAs) | 60 | Israel |
| Total arsenic (tAs) | 100 | Mercosur |
| Mercury, total (tHg) | 10 | Hong Kong |
| Methylmercury (MeHg) | control&sup4; | screened |
| Cadmium (Cd) | 20 | CH |
| Hexavalent chromium (Cr-VI) | n/m³ | controlled |
| Nickel (Ni) | 400 | EU |
| Tin (Sn) | n/m³ | controlled |
| Aluminium (Al) | control&sup4; | screened |
| Total chromium (Cr) | 500 | Hong Kong |
All values µg/kg (ppb), as-sold 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. &sup4; no sovereign maximum exists for this analyte in this product, but a credible exposure pathway does — it is screened on every lot under ALARA against the tightest analogous reference, not assigned an invented number.
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 Non-Root Vegetables across 173 certified-market samples. The pooled distribution centres on a median of 39 ppb and reaches 3.2 mg/kg at the 95th percentile. Dearing 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 3.6 mg/kg, at or above the government ceiling of 50 ppb, so the government maximum binds. Why lead is limited →
1 study in the certified-market pool measured total arsenic in Non-Root Vegetables across 163 certified-market samples. The pooled distribution centres on a median of 224 ppb and reaches 1.5 mg/kg at the 95th percentile. Dearing 2025.
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 1.5 mg/kg (provisional), at or above the government ceiling of 100 ppb, so the government maximum binds. Why total arsenic is limited →
3 studies in the certified-market pool measured cadmium in Non-Root Vegetables across 266 certified-market samples. The pooled distribution centres on a median of 18 ppb and reaches 251 ppb at the 95th percentile. Dearing 2025, Wang 2023, Ametepey 2018.
HMTc sets 20 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 346 ppb, at or above the government ceiling of 20 ppb, so the government maximum binds. Why cadmium is limited →
1 study in the certified-market pool measured nickel in Non-Root Vegetables across 163 certified-market samples. The pooled distribution centres on a median of 1.1 mg/kg and reaches 8.4 mg/kg at the 95th percentile. Dearing 2025.
HMTc sets 400 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 8.6 mg/kg, at or above the government ceiling of 400 ppb, so the government maximum binds. Why nickel is limited →
The corpus holds 1 measurement of aluminium in Non-Root Vegetables (36 samples reported across those studies), which the determination below is tested against: Wang 2023.
HMTc sets no standalone aluminium limit for Non-Root Vegetables. No credible sovereign government sets an aluminium contaminant maximum level for any fruit, vegetable or produce form in any jurisdiction. The register's aluminium limits are drinking-water and bottled-water parameters, infant-formula maximum levels, a food-contact plastics specific migration limit, toy migration limits, and permitted-additive levels for baked and starch foods; none of them regulates aluminium as a contaminant of produce. Aluminium is also the third most abundant element in the earth's crust and appears in produce largely as soil-derived and root-associated mineral content rather than as process contamination, so no near-neighbour read-across is supportable either. Under the government-limit-only method HMTc publishes no standalone aluminium number for this row. The analyte is controlled by Total aluminium by ICP-MS on every lot, reported to the applicant. Document any aluminium-containing processing aid, packaging contact or anti-caking agent, comply with the additive rules of every market of sale, and investigate any result that is an outlier against the applicant's own lot history, not a standalone number. Why aluminium is limited →
Risk Flag
Where certification is demanding for this subcategory, and why. These carry a natural or process background that runs above the limit — the limit being the strictest government maximum for the product, never a percentile of market data (Method v2.0). A product is not disqualified by this — only its own tested result decides certification, and a well-sourced lot can sit well below the market.
Nickel
Legumes, nuts, cocoa, and oats are naturally high in nickel.
Total arsenic
Rice and rice-derived ingredients carry high total arsenic; where the category sets total arsenic as a firm ceiling rather than a speciation screen, rice-based products run above it.
Multipliers are the ratio of the pooled occurrence median to the published limit; occurrence characterises the market only and carries no compliance weight. See the cross-category summary.
Cite this standard
Pendergrass, K. (2026). Non-root vegetables (fruiting, brassica, bulb, stem and legume vegetables): 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.