A pesticide panel is a multi-residue test for a fixed list of insecticides, fungicides, miticides, plant growth regulators and herbicides. Regulated markets publish their own lists, often 60-100 or more compounds, each with an action limit. Labs run the panel by LC-MS/MS and GC-MS/MS because no single technique covers all the chemistries.
In practice
A COA lists each compound with a result (often ND), the LOD or LOQ and the limit. A pass means none exceeded its limit, not that none were present. The panel only finds what's on the list: a compound outside the list isn't tested. Contamination can come from direct sprays, drift, contaminated inputs, or reused equipment. Limits and lists differ by jurisdiction; check local rules. For home growers, the safest route is an IPM approach that avoids residues on flowering plants in the first place.
µg/g (ppm) or µg/kg (ppb). Many action limits sit at 0.1 µg/g or lower.
Don't confuse with
- Residual solvents: leftover extraction solvents, a separate test.
- Heavy metals panel: elements, not organic residues.
- Organic certification: a production standard, not a residue test.
LC-MS couples liquid chromatography with mass spectrometry, identifying compounds by mass as well as retention time; it is used for pesticides, mycotoxins and detailed cannabinoid profiling.Gas chromatography (GC) separates volatile compounds in a heated gas stream; it is used for terpenes and residual solvents and decarboxylates acid cannabinoids in its hot inlet.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.ND (non-detect) on a COA means the compound was not found at or above the method's limit of detection; it does not mean the amount is zero.The LOD (limit of detection) is the lowest amount of a compound a method can reliably tell apart from zero, but not necessarily measure accurately.Integrated pest management: preventing and controlling pests by combining monitoring, prevention, cultural, biological and, as a last resort, chemical tools against set action thresholds.A residual solvents test measures leftover solvents such as butane, propane, ethanol or hexane in an extract, usually by headspace GC, against safety limits.A heavy metals panel measures toxic elements, usually lead, arsenic, cadmium and mercury, in a cannabis sample, typically by ICP-MS, against regulatory action limits.
