photo of young cannabis plants washington state

The Washington Liquor and Cannabis Board (“LCB”) is revisiting its cannabis pesticide rules in acknowledgment that its current “zero tolerance” action levels for certain pesticides is probably untenable.

LCB’s April 19, 2017 emergency rule-making proposes minimum action levels for banned pesticides in marijuana crops, and represents an official recognition that many of the chemicals found in pesticides occur in the natural environment, and that laboratories cannot test down to the zero levels required in a “zero tolerance” regulatory atmosphere.

The proposed cannabis pesticide action levels allow for small detections of certain banned chemicals, which LCB says will account for situations in which a producer has not used a banned pesticide, but it was detected in sampling as a result of, for example, cross-contamination from a neighboring farm, or residual contamination from a previous farm on the same land.

According to the LCB, even with the new action levels in place, consumers will remain protected from exposure to the toxic chemicals in banned pesticides. If a product has higher than action levels for banned pesticides, the lot from which the sample was taken would fail quality assurance testing and be subject to recall.

The LCB is considering mandatory testing of pesticides in recreational cannabis, similar to medical marijuana, but maintains that the action levels are necessary now for the random testing of marijuana crops to determine whether producers are using banned pesticides.

The adoption of the new action levels do not change prohibitions on the use of banned pesticides, and it remains a violation to intentionally use any of the banned pesticides in either recreational or medical marijuana production. A list of banned analytes and their CAS registry numbers can be found at WAC 314-55-108.

New rules also require labs to pass proficiency tests twice a year in order in three proficiency testing programs: potency testing, microbial analysis, and residual solvent testing.

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