Cannabis smoke more toxic than tobacco

Canadian researchers have discovered that there are more than 4,000 substances in cannabis smoke - many of which aren't that good for you:

The scientists first analysed smoke that would be inhaled directly, but later examined "sidestream smoke", which accounts for 85% of the fumes you inhale if you sit next to a smoker. This smoke contained higher levels of almost every toxin measured, except for compounds known as polycyclic aromatic hydrocarbons, which were more concentrated in directly inhaled cigarette smoke.

The chemicals combine to cause harmful health effects. Polycyclic aromatic hydrocarbons have been linked to reproductive disorders and cancer, while, at high levels, ammonia can cause asthma.

"Cannabis contains similar carcinogens to tobacco, in particular volatile organic compounds," Stephen Spiro of the British Lung Foundation told New Scientist magazine.

"That these exist in similar or even higher proportions to tobacco smoke is a great worry."

While it's been known for some time that consuming cannabis is definitely a safer route for self-administration, and that mouth-smoking is safer for those who must smoke (Erowid published a report on this a few years back), it'll take more than a few scientific reports to get those bongs out of dormitory rooms across the world.