Researchers who compared the effects of marijuana smoke to tobacco smoke concluded that smoking marijuana did as much cellular and genetic damage as smoking cigarettes, although only tobacco smoke damaged chromosomes, the CanWest News Service reported Aug. 6.
Study author Rebecca Maertens of Health Canada and colleagues conducted animal and bacterial studies to compare the effects of smoking tobacco and marijuana. Maertens said the researchers wanted to test the claim that marijuana is less harmful because it is a natural product.
Marijuana advocate Marc Emery challenged the findings, saying, “Where is the proof of this DNA damage to Canadians? Are there mutations in the 15 million Canadians who have smoked marijuana in the last 45 years?”
The study appears in the journal Chemical Research in Toxicology.