Iowa cannabis testing requirements

Required tests

• Potency
• Pesticides
• Residual solvents
• Heavy metals
• Microbials
• Homogeneity
• Other (see notes)

ISO/IEC 17025 accreditation

Required. Iowa Code §124E.2(8) defines a testing 'laboratory' as the State Hygienic Laboratory or an independent lab accredited to ISO/IEC 17025 by an ISO-approved accrediting body, holding a DEA controlled-substance registration and an Iowa Board of Pharmacy registration. The statute names the State Hygienic Laboratory directly and does not attach the accreditation clause to it. Certificates of analysis must meet ISO/IEC 17025:2017, and non-accredited results must be flagged (641 IAC 154.51).

Notes

• Classified 'limited' because the statute frames the program around 'medical cannabidiol' (Medical Cannabidiol Act, Iowa Code ch. 124E) with a 4.5 g total-THC-per-90-days dispensing cap, which a practitioner can waive. There is no flower, smoking or THC-infused edibles. Products may contain THC, and HHS now calls it the 'Medical Cannabis Program'.
• Lab rules are 641 IAC 154.47–154.54 ('Laboratory Testing'). HHS's Laboratory Testing Requirements & Acceptance Criteria document (v4.3, 9/7/2020) sets sampling, action levels and pass/fail criteria (154.47(1)).
• Potency: THC, THCA, CBD and CBDA for each lot. Package lots must test within ±30% of label claims for total THC and CBD.
• Contaminants (641 IAC 154.50(2)): residual solvents and processing chemicals, pesticides, microbiological impurities, heavy metals. Acceptance criteria set metals (arsenic, cadmium, lead, mercury), a pesticide list, and solvent limits. Microbials cover total aerobic count, yeast and mold, Aspergillus, Shiga-toxin E. coli and Salmonella.
• Homogeneity: the statute requires testing 'as to content, contamination, and consistency'. Standard package-lot testing runs 30 potency tests per formulation with RSD ≤20% (RPD ≤20% for reduced testing).
• 'other' = stability testing: manufacturers must run it to set product expiration dates (641 IAC 154.29(4)). Vape cartridge hardware also needs a metals validation per new cartridge lot (acceptance criteria §7.5).
• Testing cadence: process lots (extracts) are tested for metals, pesticides and solvents. After validation, 'reduced spot-check' testing applies: one process lot per quarter, for up to two years. Package lots are tested for potency and microbials before delivery to dispensaries.
• No mycotoxin panel was found in the rules or acceptance criteria (Aspergillus is tested as a microbial). No terpene, water activity, moisture, foreign matter or vitamin E acetate requirement was found.
• Labs must have no equity ownership in a manufacturer (124E.2(8)) and are reviewed yearly by HHS (641 IAC 154.47(6)). Manufacturers pay all testing costs.
• 2026 law: HF 990 (approved 6/2/2026, effective 7/1/2026) changed registration-card data and dispensary licensing, letting HHS license up to ten dispensaries instead of five. It did not change lab testing. The lab rules (154.47–.54) were last substantively amended by ARC 8124C (effective 8/14/2024); the chapter got an editorial update in the 6/10/2026 IAC Supplement.