Why are there metal particles in never-used cannabis vapes?

Metal nanoparticles have been found in cannabis vaping liquids before they’ve even been heated. This runs counter to previous research that has suggested the metals released by cannabis electronic cigarettes come from particles emitted when their coils are heated. This discovery of metal contamination in cannabis vaping liquids that were less than six months old and never used suggests that it might result from the production process.

The new research, which was a collaboration between Health Canada and the National Research Council of Canada’s Metrology Research Centre, was presented at the spring meeting of the American Chemical Society by Andrew Waye, who manages the research programme of Health Canada Office of Cannabis Science and Surveillance.