An assessment of heavy metal contaminants related to cannabis-based products in the South African market
In this 2021 article published in Forensic Science International Reports, Viviers et al. present their findings of a wide assessment of heavy metals content in South African cannabis products. Noting a dearth of such research in the South African market, the authors acquired 310 samples (representing seven different sample types) from “cultivators of plants, producers of products, importers, resellers, and pharmaceutical manufacturers” and had them analyzed for their various residues. The authors turned to inductively coupled plasma mass spectrometry (ICP-MS), the United States Pharmacopeia (USP) <232>/<233> and the International Council for Harmonisation of Technical Requirements for Pharmaceuticals for Human Use (ICH) Q3D to guide their analyses. After a brief discussion of materials and methods, the authors present their results and conclusions. They found “among all residues analyzed, a Class 1 residue will be present in a third of all samples” (cadmium, lead, arsenic, and mercury), 15% of all samples failed heavy metal analysis “when compared against the USP <232>/<233> and ICH Q3D oral specification limit,” and 44% failed when compared to the specified inhalation limits. The conclude that “when considering the results obtained, it is exceedingly necessary to have an appropriate quality control system in place, especially for heavy metal residues analysis in the current South African market. “
