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Evaluating the Risks of Pesticides and Herbicide Exposure in Cannabis

The legal verdict that awarded Plaintiff Dewayne Johnson $289 million in damages after developing cancer from exposure to the popular herbicide Roundup is certain to have repercussions that extend beyond Monsanto’s liability. Glyphosate, the active substance in Roundup, is the most popular herbicide in the world. Glyphosate can be found in surface water, rainwater and soil. The finding that Monsanto “acted with malice and oppression” when selling Roundup to consumers may signal to other manufacturers that products that contain glyphosate and other chemicals of concern could be the next targets.

One industry where exposure to herbicides and pesticides is a source of concern is the California cannabis market.  The threshold problem faced by the industry is a lack of information. According to experts in the cannabis industry, glyphosate is not among the 66 residual pesticides that are mandated for testing by the California Bureau of Cannabis Control (BCC).  For this reason, many testing facilities are not able to – or, are not requested to – confirm the presence of glyphosate in cannabis. A plethora of Proposition 65 “Notices of Violation” to cannabis dispensaries and manufacturers have alleged that their products contain pesticides that are listed under Proposition 65 such as myclobutanil, carbaryl and malathion. Meanwhile, consumers and cannabis sellers have been vocal in demanding that toxin-free cannabis be made available.

Because cannabis is still classified as a Schedule I substance under the federal Controlled Substances Act, federal agencies such as the Environmental Protection Agency, the Food and Drug Administration or the Consumer Product Safety Commission cannot play a role in evaluating cannabis products, as they do for other products. Thus, testing and regulation standards for pesticides in cannabis products are the responsibility of the states. California began requiring testing procedures on July 1 of this year, establishing cannabis product parameters from pesticide concentration to THC content to other quality issues. From July 1 to August 29, approximately 10,700 product batches were tested and 1,904 were rejected. Approximately 400 of those were rejected for pesticide levels exceeding the BCC’s action levels for those substances. In other states such as Oregon and Colorado, mandatory testing procedures have been effective in reducing the concentration of pesticides in cannabis.

California’s cannabis testing requirements are stringent. In any highly regulated market, it is not uncommon to see “fail” test results, especially at the beginning of a new and rapidly growing industry. Particularly here, because cannabis was illegal for so many years, it will take time to improve practices and procedures for cannabis cultivation and cannabis product manufacture. Myclobutanil, for example, can be taken up by the cannabis plant and remain present in the plant for several subsequent generations even if no myclobutanil is ever applied again. As the industry evolves and cultivation practices are refined, California regulators and cannabis consumers can expect to see significant improvements in “pass” rates for required testing.

Grimaldi Law Offices has been advising clients for over 20 years on chemical and product law. For knowledgeable advice and in-depth analysis on your Prop 65 compliance obligations, contact Grimaldi Law Offices at (415) 463-5186 or email us at [email protected].

Ms. Grimaldi maintains a diverse environmental law practice focusing on chemical and product regulation and litigation defense. Her practice areas include Proposition 65, California's Safer Consumer Products Regulations, California's Rigid Plastic Packaging Container Act and the federal Toxic Substances Control Act. Ms. Grimaldi graduated from the University of California Hastings College of the Law magna cum laude and holds a Bachelor of Science Degree in Bacteriology from University of California, Davis. Prior to attending law school, she worked as a research assistant in laboratories at the University of California, San Francisco Cancer Research Institute and at the University of California, San Francisco School of Medicine.