Cannabis quality testing has become an increasingly important service as more cannabis products are becoming legalized and making their way onto the market. While there are many steps that go into testing plants, concentrates and matrices such as baked goods and candy for pesticides, microbes and heavy metals prior to packaging and distribution, potential contamination from devices such as vape cartridges could be an overlooked hazard, a recent study shows. Analysts from the cannabis testing lab Medicine Creek Analytics published the results of experiments that showed cannabis vape products with metal components may leach copper, lead and other heavy metals that could then be inhaled by the user.
The researchers used UHPLC with UV detection to test 13 randomly purchased cannabis vape cartridges being legally sold in Washington state. A two-impinger liquid system and tubing condensation method were used to collect aerosol samples. The researchers also utilized ICP-MS to determine the background metal concentrations of blank stock flower, concentrate and distillate, and ran tests involving non-cartridge heating methods of cannabis flower and concentrate as well.
The results of the tests showed that chromium, copper and nickel were present in the cannabis oils and vapor phases of the cartridges, as well as smaller concentrations of lead, manganese and tin. Samples that were heated using non-cartridge methods did not have the same metal content, suggesting that the metal heating elements of the cartridge system are the source of contaminants leaching into the product. The authors wrote that the contaminant levels in the aerosol samples could lead to an acute intake of metals above regulatory standards when inhaled. This study was published in Chemical Research in Toxicology.
“As safety and compliance testing regulations evolve, it will be important to include more than the standard As, Cd, Hg, and Pb to the list of regulated metals,” the authors wrote.