Others’ cigarettes: threat to health?

Press, 20 September 1980, Page 12

Others’ cigarettes: threat to health?

Smokers are coming under increasing fire. Not only are they being badgered to give up the weed for their own sakes, but now they are also being told that their nasty habit could endanger the (health of others, and that the easy. way out — a switch to lower-tar cigarettes — is no answer to this..

Research just published by the Laboratory of the Government Chemist in Britain shows that the tricks used to protect the smoker himself, by lowering the tar and nicotine content of the smoke leaving the butt end of a cigarette, increase the concentration of pollutants in the smoke leaving the burning end (see chart).

The evidence that smokers put their own well-being at risk is incontrovertible. . That is ample justification for educational campaigns and deliberate economic pressures (curbs on advertising, higher tobacco taxes) to discourage the habit — above all, to discourage the young from getting hooked. To date, however, unrepentant smokers (like people who refuse to wear seat belts) have been able to argue that they are entitled to take their own risks. How strong is the evidence that they are risking the health of others? To be sure, unborn babies in the wombs of smoking mothers or people with chronic lung or heart diseases regularly cooped up with heavy smokers could be harmed. But the debate over involuntary, or “passive,” smoking is not about (apparently) healthy gories or people. It is about (apparently healthy non-smokers.

Reviewing the thenavailable evidence, the 1979 report of America’s surgeon general concluded: “Healthy non-smokers exposed to cigarette smoke

have little or no physiological response to the smoke, and what response does occur may be due to psychological factors.” That judgment failed to

quash the debate, however. For good reason. The surgeon general had little to go on. Almost all the hard scientific evidence of the health hazards of smoking has come from studies ot smokers themselves. Studies touching on the risks of passive smokers have tended to be anecdotal or hypothetical. This dearth of information explains the excitement with which, earlier this year, the sober “New England Journal of Medicine” greeted a study by two Californian researchers into the effects of long-term passive smoking. The strengths of the study, by Dr James White and Dr Herman Froeb, were several: — They chose a clearly measurable index of physical change, testing their subjects for any restriction in the function of the small air passages of the lung: —They worked with a substantial and carefully sample, winding cp with 2100 subjects after eliminating candidates who had a history of illness or who had lived or worked in smoggy or industrially polluted areas; — They divided the remaining subjects into six groups depending on their exposure to smoking over 20 years or more: 200 non-smokers unexposed to smokers at home or workplace; 200 passive smokers (ie, non-smokers exposed to smokers at work though not at home); 100 non-inhaling smokers; 200 light smokers (inhaling one to 10 cigarettes a day), 200 - moderate smokers (11-39 cigarettes a day) and 200 heavy smokers; — They checked up on non-smokers’ reports of their exposure to smokers at work by placing portable recorders of carbon monoxide in 80 offices.

The results of the study? Non-smokers, unexposed to smokers at home or workplace, scored best on the tests of lung function. Passive smokers scored no better than light smokers or those who did not inhale. Conclusive evidence for the anti-tobacco lobby? Well, no. Although there seems no question that the (minor) reduction in lung function reported .in the study is real, neither is there any evidence that it matters.

Much more evidence ■will be needed before the debate about the possible health hazards of smoking for non-smokers will be resolved.

But the Californian study (and a rather more hypothetical one on smoking and indoor pollution recently published in the magazine “Science”) reinforce the case for persuading more smokers to kick the habit.

E.E.C. experts at present debating the finer technical points of harmonisation of tabacco taxes please note: in this area, tax should reflect a health policy.