Doctors have said that 30 000 Britons a year might eventually die from smoking dagga and have called for a battle against the drug to mirror that belatedly waged against tobacco.
Their warning, made in an editorial in the British Medical Journal last week, is the most high-profile attempt yet to alert authorities to public health difficulties that might result from an apparently more liberal attitude to the drug.
The authors, from Imperial College, London, and St Mary’s hospital, London, argued that 120 000 deaths result among 13-million tobacco smokers each year, from cancers, respiratory disorders and heart and lung disease. If the health effects were the same, the corresponding figure from 3,2-million cannabis smokers would be 30 000.
They conceded their extrapolation could be seen as scare-mongering, but John Henry, a medical professor and one of the authors, said the real message was that medical authorities must not be caught out as they were by the results of tobacco consumption, which took 50 years of research before any concerted opposition.
”Even if the number of deaths attributable to cannabis smoking turned out to be a fraction of the 30 000 we believe could be possible, cannabis smoking would still be described as a major health hazard. If we also add in the likely mental health burden to that of medical illness and premature death, the potential effects of cannabis cannot be ignored,” said William Oldfield, a senior registrar at the hospital.
He said dagga and nicotine had different modes of inhalation. Dagga smokers take in larger volumes and hold the smoke down far longer.
”These could all contribute to illnesses of the heart and respiratory system, particularly as the chemicals in cannabis smoke are retained to a much higher degree,” Oldfield said.
The doctors say the level of dagga’s active ingredient THC is much higher today than 20 years ago. It has a marked effect on heart and blood vessels and sudden deaths have been attributed to dagga smoking.
The British Lung Foundation says that three joints a day might do as much damage as 20 cigarettes. But there has been scepticism over such claims, including among anti-smoking campaigners. The critics say, for instance, that tobacco users tend to carry on smoking for far longer and that dagga appears to be far less addictive.
The critics also question the claim that Britain has 3,2-million dagga smokers and say this is the estimate for people who have used dagga in the past year; far fewer Britons use dagga regularly. — Ã‚