Compliance testing is the lab analysis a regulator requires before cannabis or hemp can be sold, or to confirm a hemp crop is under the THC limit. Typical panels cover cannabinoid potency, moisture or water activity, microbial contaminants, mycotoxins, pesticides, heavy metals and residual solvents for extracts.
In practice
For potency, many systems report total THC, calculated as THC + 0.877 x THCA, so that acidic THCA (which converts to THC on heating) is counted. Hemp rules may require sampling within a set number of days before harvest. A failed microbial test can lead to destruction, remediation, or decontamination such as irradiation where permitted.
Compliance numbers are only as good as the lab and the sampling. Studies of legal markets show results vary systematically between labs and labels often overstate potency (Jikomes & Zoorob 2018; Schwabe et al. 2023). GenetixBay criticises the practice of lab shopping and inflated results, not named businesses.
Rules differ by country, state, province and city, and change often. This is a general definition, not legal advice: check local rules.
Don't confuse with
- R&D testing: voluntary testing for a breeder or grower's own information.
- Certificate of analysis (COA): the report a test produces.
Hemp is cannabis grown for fibre, seed or other uses and, in many laws, defined as Cannabis sativa with no more than 0.3% THC by dry weight.THC (Δ9-tetrahydrocannabinol) is the neutral, decarboxylated cannabinoid mainly responsible for cannabis's reported intoxicating effects; the living plant makes it almost entirely as THCA.Potency testing is laboratory measurement of a sample's cannabinoid content, normally by HPLC, reported as % w/w or mg/g for each cannabinoid plus calculated totals.A 0-1 measure of how freely available the water in a material is; for dried cannabis flower the accepted range is about 0.55-0.65 aw.Mycotoxins are toxic compounds made by certain moulds, such as aflatoxins and ochratoxin A from Aspergillus and Penicillium species; cannabis labs test for them at parts-per-billion levels.Total THC is a calculated figure, Δ9-THC plus 0.877 × THCA, estimating the maximum THC a sample could yield after full decarboxylation.THCA (tetrahydrocannabinolic acid) is the acid cannabinoid that drug-type cannabis makes in its trichomes; heat or time decarboxylates it into THC, losing about 12% of its mass.A COA (certificate of analysis) is a lab's signed report of what it measured in a specific sample, such as cannabinoids, terpenes, moisture and contaminants, with methods and limits.Cannabis irradiation is treating harvested flower with ionising radiation, gamma, electron beam or X-ray, to cut microbial counts; permission and labelling rules vary.Lab shopping is the practice of choosing testing labs because they report higher potency or more passing results, rather than because they are most accurate.
