COAs and testing
What does ND mean on a COA, and what is LOQ?
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ND means "not detected" above the lab's limit of quantitation (LOQ), the smallest amount the method can measure reliably. It is not zero. With a 0.01 percent LOQ, a 30 mL bottle can still hide up to 2.8 mg of THC, which matters against the 0.4 mg per container cap effective December 11, 2026 (7 U.S.C. 1639o).
"ND" is the most important two letters on a CBD lab report and the most misread. It is the basis for every "THC-free" label, and it means something narrower than the label implies. This page explains what a laboratory is actually saying, how to convert it into milligrams, and why the number behind it decides whether a product can ship to Washington, California, or anywhere after December 11, 2026.
What does a lab mean by ND?
A laboratory reports a result as ND, not detected, when the measured signal for that analyte falls below the method's limit of quantitation. The LOQ is the lowest concentration the instrument and method can measure with acceptable accuracy and precision; below it, the lab will not put a number on the result. Some reports also list a limit of detection (LOD), a lower threshold where the analyte can be seen but not reliably quantified. Results between LOD and LOQ are sometimes flagged as "<LOQ" rather than ND.
So ND means "less than the LOQ." It never means zero. The LOQ is set by the method, the instrument and the matrix (oil behaves differently from gummy), and it varies between laboratories. Measurement uncertainty is a separate figure; USDA defines it as the parameter "that characterizes the dispersion of the values" that could reasonably be attributed to the quantity measured (7 CFR 990.1).
How do I turn an LOQ into milligrams?
Multiply the LOQ (as a fraction) by the mass of the container's contents. Worked examples for a 30 mL tincture with roughly 28 g of oil:
| LOQ for THC | Maximum THC hidden behind "ND" in 28 g |
|---|---|
| 0.05 percent | 14 mg |
| 0.01 percent | 2.8 mg |
| 0.005 percent | 1.4 mg |
| 0.001 percent | 0.28 mg |
Now compare with the federal cap. From December 11, 2026, a final hemp-derived cannabinoid product is excluded from the hemp definition if combined THC exceeds 0.4 milligrams per container (7 U.S.C. 1639o). Only the last row in that table proves compliance. An ND at 0.01 percent is a weaker statement than it looks: the bottle could contain seven times the cap.
The same arithmetic applies to THCa, since total THC counts 0.877 times THCa (7 CFR 990.1). Both rows need to read ND at an adequate LOQ.
Why does the LOQ decide which states a product can ship to?
Because the strictest states regulate detectable THC, not a percentage. Washington's Liquor and Cannabis Board says it is illegal for unlicensed stores to sell products with any detectable levels of THC (WSLCB). California's Department of Cannabis Control states that "if a hemp product contains any detectable amount of THC, it is considered intoxicating" (CA DCC). "Detectable" in practice means "detected by a competent lab at a low LOQ," so a product tested with a coarse method is a weaker candidate for those states than one tested with a sensitive one.
Label claims are no substitute. A 2017 JAMA analysis of 84 online CBD extracts found THC in 18 of them (21.43 percent), at up to 6.43 mg/mL (JAMA 2017).
What should I ask for?
- The LOQ for THC and THCa, printed on the report. If it is missing, ask the lab or the brand.
- ND for both analytes at an LOQ low enough that LOQ times container mass stays under 0.4 mg. For a 30 mL tincture that means about 0.001 percent; for a 30-count gummy jar of 120 g it means about 0.0003 percent.
- A laboratory accredited to ISO/IEC 17025:2017, the standard ISO says lets labs show they "operate competently and generate valid results" (ISO).
Reports on this site print the LOQ beside each cannabinoid line so you can run that check yourself. The five-step walkthrough is at How do I read a CBD lab report?.
General information, not personalized guidance.
Sources
- 7 U.S.C. 1639o, Definitions (hemp) Cornell Law School, Legal Information Institute (accessed 2026-10-13)
- 7 CFR 990.1, Definitions Cornell Law School, Legal Information Institute (accessed 2026-10-13)
- Hemp and Synthetic THC Products Washington State Liquor and Cannabis Board (accessed 2026-10-13)
- Hemp California Department of Cannabis Control (accessed 2026-10-13)
- Labeling Accuracy of Cannabidiol Extracts Sold Online JAMA, via PubMed Central (accessed 2026-10-13)
- ISO/IEC 17025, Testing and calibration laboratories International Organization for Standardization (accessed 2026-10-13)
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