Vaporized cannabis extracts may contain lead and other heavy metals

The vapes pen and other devices for vaporizing cannabis extracts - most often distillate - have gained in popularity as a practical and potentially safer alternative to traditional combustion methods.

New research highlights the hidden dangers of this method of consumption. In addition to heavy metals that can be discharged by the appliances used for consumption, the presence of toxic metal particles in cannabis vaping «liquids», even before the device is heated, is a cause for serious concern.

The prevalence of metallic contamination

The study, presented by Andrew Waye and his team at the spring meeting of the’American Chemical Society, reveals alarming results on the contamination of cannabis vaping «liquids». Unlike nicotine vapes, which have come under closer scrutiny, cannabis vapes have remained relatively unexplored territory until recently. The research conducted by Waye and his colleagues at Health Canada's Office of Cannabis Science and Surveillance aims to fill this crucial knowledge gap.

Mr Waye's team discovered worrying levels of metal contamination in the cannabis extracts from vape pen legal and illegal. These contaminants, including nickel, chromium and lead, pose serious health risks to consumers.

Some illegal samples contained lead levels exceeding acceptable limits by a factor of 100. Even more alarming, this contamination was detected in vape pen that were less than 6 months old. It would therefore come from the appliance itself, rather than from the heating process. The study does not say whether extracts were analyzed before being put into vaper cartridges.

Metal contamination levels also varied within the same batch.

The size of the metal particles detected is another source of concern. Using advanced imaging techniques, the researchers identified nano-sized particles in cannabis vaping liquids. These particles, characterized by their high reactivity, can be very harmful when inhaled into the lungs.

For the future, the researchers are seeking to determine the extent to which metal particles are transmitted in vaping aerosols - the vapor released and inhaled - during device use. This step will be crucial in assessing public health consequences of metal contamination in cannabis vapes.