Illegal pesticides have recently been found at licensed and unlicensed cannabis grow sites in California. These pesticides which are dispersed as chemical fumigants contain prohibited and uncharacterized chemicals posing risks to consumers of marijuana products. Seizures conducted at illicit marijuana grow sites throughout the state of California have revealed a pervasive use of illegal pesticides with a common reoccurrence of “Blue Bag Pesticides.” These products violate multiple laws and statutes regarding their labelling, chemical contents, and directions for use. This work discusses the current landscape of illegal pesticides in cannabis cultivation and the unmitigated exposure risks they pose to consumers of cannabis products. The contents of unused “Blue Bag Pesticides” have been analyzed by gas chromatography- mass spectrometry (GC-MS), pyrolysis-GC-MS (Py-GC-MS), two-dimensional-GC-MS (GCxGC-MS), and liquid chromatography- tandem mass spectrometry (LC-MS/MS) to characterize their chemical compositions. Multiple techniques were undertaken to perform an in-depth chemical fingerprinting of these products. This work serves as a first step toward mitigating public exposure to these chemicals through cannabis materials and off-target exposures. This work also identifies vulnerabilities in the current regulatory requirements for residual pesticides testing, as set forth by the California Department of Cannabis Control. Subsequent analyses will investigate the direct relationship between seized pesticide composition, their use as fumigants, and the detectable pesticides present on marijuana plants. This work was performed under the auspices of the U.S. Department of Energy by Lawrence Livermore National Laboratory under Contract DE-AC52-07NA27344. This work was supported by LDRD project tracking code 25-ERD-025, tracking number LLNL-ABS-2004054.