Pesticides in California’s Adult-Use Cannabis Market: Prevalence, Analytical Challenges and Concerns, and Regulatory/Market Solutions

The analysis of pesticides in cannabis flower and extracts has become commonplace in the years since after legalization of cannabis for medical and adult use. Most states with legal programs have regulatory requirements for residual chemical residues, including pesticides. Since 2018, California has required testing for 66 pesticides, mandating all retail products be screened for these pesticides through regulatory compliance testing with state-licensed laboratories.

Shelf testing of retail vaporizer and flower products in late 2023 - early 2024 by licensed laboratories Infinite Chemical Analysis Labs and Anresco Laboratories revealed the pervasive presence of certain pesticides, including the regulated pesticide chlorfenapyr, in some instances at levels hundreds of times higher than permissible. Concurrent and subsequent testing of retail products and in-progress material for unregulated residues identified more than 70 additional pesticides beyond the regulated list. Data on prevalence of regulated and unregulated pesticides in the California market will be presented, along with discussion of analytical challenges, gaps in testing protocols, and solutions being implemented by regulatory agencies and engaged stakeholders to provide more tailored and effective oversight of pesticide residues in the cannabis market.