How to Read a Pesticide Screen on a COA

Published May 4, 2026

The Quick Answer

A pesticide screen on a hemp COA tests 60+ common agricultural chemicals for detectable residue in the flower or extract. Every entry should read 'Not Detected' or 'ND' — 'Passing' at trace levels is technically legal but not ideal. Look for the phrase '

Why the Pesticide Screen Matters

Cannabis is bioaccumulative — it absorbs and concentrates chemicals from the soil and environment. Pesticides used during growth don't just wash off. They persist through cure, get concentrated when the flower is extracted, and end up in your lungs when you smoke or vape. That's why a clean pesticide panel is one of the most important safety indicators on a COA.

The 4 Categories of Pesticides Tested

1. Miticides (for Spider Mites)

Common miticides include abamectin, bifenazate, and spiromesifen. Spider mites are the most common indoor cannabis pest, so miticides show up on almost every ban-list. Some (like abamectin) are neurotoxins.

2. Fungicides

Mold and powdery mildew fungicides include myclobutanil, triflumizole, and pyraclostrobin. Myclobutanil is particularly concerning because it produces hydrogen cyanide when heated — a smoker exposure risk.

3. Insecticides

Standard broad-spectrum insecticides include chlorpyrifos, imidacloprid, and diazinon. These are the most commonly banned in cannabis production because of their neurotoxicity and persistence in plant tissue.

4. Plant Growth Regulators (PGRs)

PGRs like paclobutrazol and daminozide are used to force bigger, denser buds — but they're linked to health concerns and produce a distinct 'plastic' harshness on the smoke. Cannabis grown with PGRs often looks unnaturally uniform and shiny.

What Each Result Means

'ND' or 'Not Detected'

The gold standard. The lab's testing equipment couldn't detect any residue at all. That means the flower or extract is either genuinely clean or tested below the equipment's detection floor (usually parts-per-billion levels).

'<LOQ' (Below Limit of Quantification)

The lab detected trace amounts too small to measure precisely. Generally considered a pass, though premium brands usually push for full 'ND' across the panel.

Numeric Values With 'Pass'

The pesticide was detected at a measurable level but is below the state's regulatory limit. Legal, but not ideal — a truly clean product should have zero measurable pesticide across all 60+ tested compounds.

'Fail' or 'Exceeded Action Limit'

The pesticide is above the state's regulatory limit and the product should not be sold. If you see this on a COA that's still attached to a for-sale product, walk away and report the brand.

The 3 Biggest Red Flags

Myclobutanil detected at any level (produces cyanide when heated), PGRs like paclobutrazol at any level (linked to health concerns), and 'not tested' on any pesticide category (means the brand only ran a partial panel to hide something). A legitimate brand tests all 60+ compounds and prints all results.

View TP-G Farm Lab Results →