Toxins and pesticides in legal marijuana have been in the news lately. “Alarmingly high” pesticide residuals were found in cannabis tested at the Werc Shop, a cannabis analytical lab in Pasadena, California.
Are contaminants in cannabis a “serious concern” or a manageable side effect of prohibition?
The Werc Shop study, published in the Journal of Toxicology last month, raises serious questions about the safety of cannabis. The results show when pesticides are topically applied to cannabis, and that product is combusted, residual pesticides are found in the smoke.
Using a water bong and a pipe, two of the most common methods of smoking cannabis, the contaminant recovery rates were 42–70%. Smoke filtered through cotton and coconut fibers did better, with residue registering at 0.08–10%. The study concludes, “considering these results, high pesticide exposure through cannabis smoking is a significant possibility, which may lead to further health complications in cannabis consumers.”
This looks bad on the surface. Especially since most users do not have access to cannabis tested for purity by third party validated labs. Dave Lampach, of Oakland’s Steephill Lab is an expert on cannabis safety. Steephill Lab, founded by Lampach and fellow entrepreneur Addison DeMoura, was the first non-federal potency, mold and bacterial cannabis-testing program in the United States. Lampach is also a member of the BOTEC team, recently hired by the State of Washington to create regulations for the production, processing and retailing of cannabis.
“I don’t think pesticides are a really big problem,” says Lampach, “But, there is always going to be that one jerk with spider mites, who uses a pesticide that you do not want inhale.”
To weed out this problem completely would require prohibitively expensive equipment, like a Triple Quad LC/MS, only to check for a rare worst-case scenario. Steephill tests specifically for a “top ten” list of chemical contaminants, rather than for the thousands of possible options. As the chemical signature of many pesticides is similar, one test will identify the presence of any member of that “family.” Ten tests at Steephill will show the presence of hundreds of different potential pesticides in contaminated cannabis.
– Read the entire article at Ladybud.