CANNABIS CANCER WARNING; Drug has more cancer chemicals than tobacco.

Byline: Ben Spencer

SMOKING cannabis can damage DNA and cause cancer, researchers have found.

They discovered marijuana contained 50 per cent more carcinogenics - cancer-causing chemicals - than tobacco.

Toxicology expert Dr Raj Singh said that his research provided the first "convincing evidence" that cannabis could damage DNA and so allow cell mutation, which adds to the risk of cancer.

Dr Singh, from Leicester University's Cancer Biomarker Prevention Group, added: "Smoking three or four cannabis cigarettes a day is associated with the same degree of damage to bronchial mucus membranes as 20 or more tobacco cigarettes a day."

It was previously thought by many that cannabis may not be as harmful as tobacco because it contains fewer chemicals.

But recent studies have suggested the opposite.

Dr Singh explained that when DNA is damaged, cells cannot control their growth pattern, which has the potential to lead to altered cells, increasing the risk of the disease.

He added: "The compound we studied is called acetaldehyde and is a major constituent of tobacco and is also found in cannabis.

"It is well known that toxic substances in tobacco smoke can damage DNA and increase the risk of lung and other cancers.

"Scientist were unsure if cannabis smoke would have the same detrimental effects from it - but we have found for the first time that it is as damaging to DNA."

The findings were published in the journal Chemical Research In Toxicology.

The researchers also point out that the ability of cannabis smoke to damage DNA had particular health implications, as users tend to inhale more deeply than cigarette smokers. This increases respiratory burden.

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