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Heavy Metal Index

Massachusetts cannabis protocol heavy-metal limits

Scope The protocol applies to finished adult-use and medical marijuana products, including plant material, cannabis resin, concentrates, and marijuana-infused products.

Scope

The protocol applies to finished adult-use and medical marijuana products, including plant material, cannabis resin, concentrates, and marijuana-infused products.

Exact limit and units

MetalMatrixLimitUnitBasis
LeadFinished marijuana products, all uses500µg/kg (ppb)Product as tested
ArsenicFinished marijuana products, all uses500µg/kg (ppb)Product as tested
CadmiumFinished marijuana products, all uses500µg/kg (ppb)Product as tested
MercuryFinished marijuana products, all uses500µg/kg (ppb)Product as tested
LeadFinished marijuana products, ingestion only1000µg/kg (ppb)Product as tested
ArsenicFinished marijuana products, ingestion only1000µg/kg (ppb)Product as tested
CadmiumFinished marijuana products, ingestion only1000µg/kg (ppb)Product as tested
MercuryFinished marijuana products, ingestion only1000µg/kg (ppb)Product as tested

The extracted paragraph states the all-use and ingestion-only limits and identifies Exhibit 4 as the four-metal table; the table itself was not cleanly extractable as text.

How tested

Quantification must use a validated method such as USP Chapter <233> or the cited FDA method. Finished vape products also receive a second heavy-metal screen under the protocol.

Enforcement posture

The protocol implements Massachusetts cannabis testing requirements under 935 CMR 500.000 and 501.000. Products above the applicable metal limits are not compliant for dispensing under the protocol.

History of changes

The extracted protocol was published for written comment on July 24, 2020 and includes updated metals and vape-product guidance.

How it compares

The all-use Massachusetts limit of 500 ppb is stricter than Nevada action levels for arsenic, lead, and mercury, but less differentiated by route than Colorado and Maryland.

Sources

Update history

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