Evaluation of illicit drug contaminants in seized cannabis in Arizona and California, 2023–2024

Despite public health concerns, fentanyl, cocaine, and other illicit drug contaminants remain largely understudied in unregulated cannabis. Here, we developed an analytical method to quantify a panel of common illicit drugs in cannabis and tested the law enforcement seizures in Arizona and California in evaluation of the illicit drug contamination in black- and gray-market cannabis. One hundred and eighteen cannabis dried flower samples were collected by the Maricopa County Sheriff's Office and the US Postal Inspection Service between 2023 and 2024. The prepared samples were analyzed using an Agilent 6495 LC-MS-MS for 16 illicit drugs. Twenty-five (21.2%) of the cannabis flower samples had detectable concentrations of illicit drugs. Only three of the 16 analytes tested were detected, including cocaine (20.3%), methamphetamine (MAMP; 3.4%), and 3,4-methylenedioxymethamphetamine (MDMA/Ecstasy; 0.9%). The highest concentration of illicit drugs was cocaine at 12,000 ppm (or 1.2% by weight). This pilot study demonstrates the presence of illicit drugs in black- and gray-market cannabis largely due to the contamination in the unkempt environment where they are being assembled and distributed. Intentional spiking appears to be rare, but the level of spiked cocaine can pose a health risk to consumers of unregulated products. Further studies are needed to survey the chemical contaminants of black- and gray-market cannabis and better understand their public health risk nationwide.