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Cannabis tinctures and sublingual oils — HMTc Standard

Standard

The Heavy Metal Tested & Certified heavy-metal-safety standard for cannabis tinctures and sublingual oils (Cannabis, Hemp, and CBD Products), evaluated on the finished oral/sublingual liquid as sold. Each limit is the strictest sovereign cannabis heavy-metal action level applicable to the ingestion route; total chromium is a screening ceiling with hexavalent chromium as the binding control, and inorganic arsenic, methylmercury and Cr(VI) are enforced by reflex speciation.

How limits are set

Cannabis has no uniform federal contaminant limit. Its heavy-metal ceilings are the route-split action levels of the credible sovereign cannabis programs — California (DCC 2026), Colorado (2022), Massachusetts (2020), Maryland (2025), Nevada (2020), and Israel (IMC-GMP 152, 2016). For each analyte the HMTc limit is the strictest maximum any of these governments sets for the product's administration route. The route basis is never conflated: the strict inhaled arsenic and cadmium action levels are never applied to an edible or a topical, and a permissive topical lead level is never applied to inhaled flower. It is a lookup, not a computation; occurrence never selects a value.

Four analytes bind directly to a sovereign action level — lead, cadmium, total arsenic, and total mercury. Total chromium is recorded as a screening ceiling rather than a health limit: it is dominated by benign trivalent chromium while the health-relevant species is hexavalent chromium, so the total-chromium action level is non-protective as a ceiling and any quantifiable Cr(VI) fails certification. Nickel, tin, and aluminium, which no cannabis program regulates for content, are held under mandatory analytical control; inorganic arsenic, methylmercury, and hexavalent chromium are enforced by reflex speciation against their measured total. Certification is heavy-metal safety only and does not endorse the efficacy or the legality of these products.

Master Limit Table

All values in ppb (µg/kg), as-sold basis. 7 of 11 analytes carry a firm ceiling; the remaining 3 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.

AnalyteHMTc limitBinding basis
Lead (Pb)500strictest government ML (US-CA)
Cadmium (Cd)500strictest government ML (US-CA)
Total arsenic (tAs)500strictest government ML (US-MA)
Inorganic arsenic (iAs)bounded≤ total tAs, measured every lot (see note)
Mercury, total (tHg)100strictest government ML (Israel)
Methylmercury (MeHg)bounded≤ total tHg, measured every lot (see note)
Nickel (Ni)800government read-across (EU)
Tin (Sn)250000government read-across (Singapore)
Aluminium (Al)100000government read-across (China)
Total chromium (Cr)screenscreening ceiling — Cr(VI) is the binding health control (see note)
Hexavalent chromium (Cr-VI)bounded≤ total Cr, measured every lot (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

For Cannabis tinctures and sublingual oils, 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.

AnalyteHMTcBindingBasis
Lead (Pb)500US-CAdirect sovereign ML
Cadmium (Cd)500US-CAdirect sovereign ML
Total arsenic (tAs)500US-MAdirect sovereign ML
Inorganic arsenic (iAs)bounded≤ tAsbounded by parent total
Mercury, total (tHg)100Israeldirect sovereign ML
Methylmercury (MeHg)bounded≤ tHgbounded by parent total
Nickel (Ni)800EUdisclosed read-across
Tin (Sn)250000Singaporedisclosed read-across
Aluminium (Al)100000Chinadisclosed read-across
Total chromium (Cr)screenCr(VI) bindsscreening ceiling (US-MD action level 1100000 µg/kg — non-protective for total Cr); any quantifiable Cr(VI) fails
Hexavalent chromium (Cr-VI)bounded≤ Crbounded by parent total

Risk Flag

On the published occurrence literature to date, Cannabis tinctures and sublingual oils 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). Cannabis tinctures and sublingual oils: HMTc standard (Standard No. 10.83138/hmtc.std.25.cannabis-tinctures-oils). Institute of Contaminant Standards. https://doi.org/10.83138/hmtc.std.25.cannabis-tinctures-oils

© 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.