Quantitative aspects of passive smoking and lung cancer

The exposure of passive smokers to cigarette smoke is estimated to be equivalent to 0.1-1.0 cigarette/day actively smoked. According to the reported relationships of dose and time, lung cancer incidence and other relative risk figures relating to nonsmokers have been calculated for ages 40, 50, 60, 70, and 79. Risks for smokers with a daily consumption of 0.1-1.0 cigarette were found to be in the range of R = 1.03 to 1.36. As it applies to passive smokers, this range of exposure may be neglected because it has no major effect on lung cancer incidence. The results of four previous studies dealing with passive smoking and lung cancer are compared with the current calculated risks, and the differences are discussed.