Smokers are being harmed by other smokers' second-hand fumes, claims groundbreaking university research Smoking rooms in non-smoking environments are 'gas chambers' where the smokers poison themselves and others, a medical academic said yesterday. The warning came from the leading anti-smoking campaigner after a university study showed smokers exposed to second-hand smoke faced an even higher risk of respiratory ailments. Anthony Hedley, chair professor of the University of Hong Kong's department of community medicine, said smokers were likely to be seriously harmed if they cloistered themselves in smoking rooms set up at catering establishments where smoking is banned. 'Smoking rooms in which there are inevitably very high levels of chemicals will cause additional hazards to health,' professor Hedley said. 'It is clear that smoking rooms will become licensed facilities for the causation of cancer, heart attack and stroke. They will become gas chambers,' he said. A total of 9,923 police officers answered questionnaires for the study between December 1995 and January 1996. Of those, 3,999 were smokers. The study was published in this month's Tobacco Control, a publication of the British Medical Journal. Lam Tai-hing, head and chair professor of the department, said it was the first study in the world showing that smokers were being harmed by other smokers. The study showed that smokers have 52 per cent more chance of having throat problems, 27 per cent chance of a cough and 29 per cent higher risk of wheezing when exposed to just one other smoker in the workplace, compared to smokers who are not exposed to second-hand smoke. The smokers also are more likely to seek outpatient treatment for their health problems, it found. The health risks increase exponentially with the number of other smokers they are exposed to. When the data is analysed using the hours of exposure to cigarettes, the same striking dose-response relationship was obtained. 'We can say that the findings are consistent and similar for throat problem, for cough and phlegm, and for wheezing,' he said. 'There is also increased health-care utilisation.' Professor Hedley said smokers were being harmed by other smokers' sidestream smoke - the smoke emitted from the burning tip of the cigarette between puffs. 'Sidestream smoke is more toxic than mainstream smoke [smoke from one's own cigarettes],' he said. 'In second-hand smoke, 90 per cent of the chemical mix comes from sidestream smoke.' He added that carcinogenic chemicals from sidestream smoke are up to 50 times more concentrated.