"Gamma irradiation is a controversial decontamination technique that has never been studied for safety in smoked or inhaled products anywhere in the world," CSA wrote in its letter. "Although it effectively destroys most bacteria, it does not destroy viruses or mycotoxins, and is often used to cover up biological contamination resulting from poor production, processing or handling practices. One of the bi-products of gamma irradiation is the production of Unique Radiolytic Products, which are a new class of chemicals resulting from irradiations that are not otherwise found in nature. Of significance in the gamma irradiation of whole plant cannabis is the potential production of cyclobutanones, which are toxic, carcinogenic chemicals that form when fats are subjected to gamma irradiation, and which have been directly linked to the development of colon cancer in rats. In addition, gamma irradiation has been shown to destroy terpenes like myrcene and linalool, which have known therapeutic properties and are found in high concentrations in some strains of whole-plant cannabis."
