The inherent risks of substance use are significantly increased for drugs procured on the illegal market, where there is no quality control and drug contents are unpredictable. Drug adulteration — the presence of substances in addition to the expected one — increases the risk of accidental poisoning and other harms because people who use drugs do not know what substances they are using or how much. This report provides a snapshot of the contents of drugs on the unregulated market in Canada, with the view to raising awareness among stakeholders, including people who use drugs, direct service providers and policy makers, that adulteration is extensive and pervasive, and contributes significantly to drug-related harms.

The report summarizes data from three primary sources:
• Health Canada’s Drug Analysis Service (DAS), which identifies substances contained in samples seized by law enforcement;
• A drug content monitoring study consisting of surveys of people who use drugs and concurrent urine screening (urinalysis) results; and
• Drug checking service providers who are members of Canada’s national Drug Checking Working Group.