COAs and testing
What contaminants are hemp products tested for?
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A full hemp panel covers five contaminant classes: pesticides, heavy metals, residual solvents, microbial contaminants and mycotoxins, plus water activity and moisture for flower. Oregon's testing rules set separate standards for each of those seven categories (OAR 333-007). A potency-only report is incomplete.
Potency tells you what is in a hemp product on purpose. Contaminant testing tells you what is in it by accident. Hemp is a bioaccumulator, extraction uses solvents, and finished goods are foods or oils that can grow things, so a complete certificate of analysis runs several separate panels. Oregon's rules are used below as the model because they set a distinct standard for each category and are published in full. The report walkthrough is at How do I read a CBD lab report?.
What are the five contaminant classes?
Oregon's testing rules in OAR chapter 333, division 7 set separate compliance standards for microbiological contaminants (333-007-0390), pesticides (0400), solvents (0410), heavy metals (0415), mycotoxins (0425), and water activity and moisture content (0420), alongside the cannabinoid potency standard (0430) (Oregon Division 7). That list is a good definition of "full panel."
- Pesticides. Hemp takes up what is sprayed on it and what is in the soil, and extraction concentrates it. Oregon requires testing "for all the analytes listed in Exhibit A, Table 3," a batch fails if any pesticide exceeds the table's action level in any sample, and the state reviews the analyte list at least every two years (OAR 333-007-0400). The exact analyte count varies by state and revision; expect several dozen compounds.
- Heavy metals. Typically arsenic, cadmium, lead and mercury. These come from soil and water and concentrate in extracts the same way pesticides do.
- Residual solvents. Ethanol, butane, propane, hexane, heptane and similar, left over from extraction. Oregon exempts processors from solvent testing only if they used no listed solvent and relied on mechanical extraction or water, animal fat or vegetable oil.
- Microbial contaminants. Salmonella, E. coli and total yeast and mold counts, relevant to flower, gummies and anything with water content.
- Mycotoxins. Aflatoxins and ochratoxin A, produced by molds on stored plant material.
Water activity and moisture content are measured on flower and other plant material to show it was dried enough that mold cannot grow in storage.
Which products need which tests?
- Flower and raw plant material: everything above, including water activity and moisture.
- Extracts, distillates and isolates: pesticides, heavy metals, residual solvents, and usually microbes and mycotoxins carried over from the input material.
- Finished tinctures, softgels and gummies: the full panel on the input extract, plus potency and, for edibles, microbial testing on the finished batch.
- Pet products: the same panel. Dogs are smaller than people, so per-kilogram exposure to any contaminant is higher.
A related category is process by-products. FDA notes that some delta-8 manufacturers "may use potentially unsafe household chemicals" in conversion and that the final product may contain harmful by-products (FDA). That is a reason to prefer naturally extracted cannabinoids and to ask a CBN supplier for a process attestation, since a standard panel does not show whether CBN came from plant degradation or reagent conversion.
Who sets the limits and who checks the lab?
Action levels come from state rules; there is no federal contaminant standard for hemp products, and states copy or adapt each other's tables. Laboratories are checked by accreditation: A2LA assesses cannabis and hemp labs to ISO/IEC 17025:2017 and adds state-specific requirements where a state has an agreement with the accreditor (A2LA). Check that the lab's accredited scope covers the specific panels on the report, not only potency. See What is ISO/IEC 17025 accreditation?.
Transparency requirements are arriving too. Oregon's Hemp Registry, in force since January 1, 2026 with enforcement from June 1, 2026, requires that "test results be made accessible to consumers" for every cannabinoid hemp product sold in the state (OLCC).
What should a passing report look like?
Every line in each panel shows a measured value or ND, the action limit, and "Pass." The lab name, accreditation number and batch number match the potency page. If a report shows potency alone, or if any panel is marked "not tested," ask for the complete document before buying from any seller. Reports linked from this site carry the full panel for each batch.
General information, not personalized guidance.
Sources
- Oregon Administrative Rules, Chapter 333, Division 7, Marijuana and Hemp Testing Cornell Law School, Legal Information Institute (accessed 2026-10-13)
- Or. Admin. Code 333-007-0400, Standards for Pesticides Compliance Testing Cornell Law School, Legal Information Institute (accessed 2026-10-13)
- 5 Things to Know about Delta-8 Tetrahydrocannabinol (Delta-8 THC) U.S. Food and Drug Administration (accessed 2026-10-13)
- Cannabis Testing Laboratory Accreditation A2LA (accessed 2026-10-13)
- OLCC Announces Hemp Registry, Bringing Transparency to the Market Oregon Liquor and Cannabis Commission (accessed 2026-10-13)
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