Arkansas cannabis testing requirements

Required tests

• Potency
• Pesticides
• Residual solvents
• Heavy metals
• Microbials
• Water activity
• Moisture
• Homogeneity

ISO/IEC 17025 accreditation

Not required. Accreditation is required, but ISO/IEC 17025 is only one accepted route: an approved lab must be accredited by NIDA, NELAC, ISO or a similar body ADH accepts, and be approved by ADH (20 CAR 202-102).

Notes

• Status is partial because adult use rests on a secondary source: Issue 4 (2022) failed 43.75% to 56.25% per Ballotpedia's certified figures; the Secretary of State's results site could not be quoted. No field is unknown.
• Regulator: ADH writes the testing and labeling rules (20 CAR Part 202) and approves labs. The Medical Marijuana Commission (DFA) licenses cultivators and dispensaries, and Alcoholic Beverage Control enforces.
• Flower batches: pesticides, water activity and moisture, THC/CBD potency and heavy metals (20 CAR 202-105(c)(1)). Water activity above 0.65 Aw fails; moisture above 15% is reported but does not fail (202-114).
• Concentrate and extract lots: pesticides, solvents, potency, heavy metals and microbes (202-106). Solvent testing is waived for mechanical, water, animal-fat or vegetable-oil extraction with no listed solvent.
• Microbes: labs screen for total coliforms, then check positives for E. coli; over 100 CFU/g fails (202-111). ADH's random program must test each product for microbes at least once a year (202-119(c)). The rules do not require Salmonella, Aspergillus, yeast and mold, or mycotoxin tests.
• Potency covers THC, THCA, CBD and CBDA (202-115(a)). A concentrate or extract lot fails if THC varies by more than 30% RSD between samples (202-115(b)), which is why homogeneity is listed.
• Act 491 of 2025 (Ark. Code 20-56-309) requires processed products (edibles, oils, concentrates, tinctures, topicals, inhalables) to be tested in finished form, including pesticides, heavy metals, microbes, residual solvents and THC/CBD.
• Pending: ADH proposed revisions to 20 CAR Part 202 to implement Act 491 (comment period July 5 to August 5, 2026; hearing August 5, 2026). As of September 28, 2026 the Code of Arkansas Rules still shows the old text.
• ADH lists four approved labs on its Medical Marijuana Resources page.
• Reported, not verified in official text: a December 2025 Arkansas Supreme Court ruling lets the legislature amend voter-approved amendments, including Amendment 98, by a two-thirds vote. No 2026 ballot measure concerns marijuana.