There have been a ton of instances in which THC vape oil cartridges have been found to be tainted with pesticides, but this remains more of an indictment on early, loosely regulated legal marijuana regimes than it does on particular companies. For example, during the 2017 Emerald Cup, 34 out of 39 cartridge entries were disqualified because of contamination.
The prevalence of contaminated weed has ushered in a whole new non-ancillary faction of the legal marijuana business—lab testing. While contamination is clearly still a factor, it is apparent that companies are attempting to do their due-diligence on the matter, especially considering the stringent regulations in weed-legal states. But it’s not a problem that’s going to be fixed overnight, as seen by the latest trials and tribulations of Xzibit.