Scientific American Experts warn of cannabis cancer 'epidemic' ABC Online, Australia - 5 hours ago Smoking a joint is equivalent to 20 cigarettes in terms of lung cancer risk, say researchers, warning of an "epidemic" of lung cancers linked to cannabis. ... Cannabis lung cancer risk equal to 20 cigarettes Radio New Zealand Lung Cancer Risk of One Marijuana Joint a Day Equals Daily Pack of ... MedPage Today Smoking One Joint is Equivalent to 20 Cigarettes, Study Says FOXNews all 56 news articles