In a case-referent study, the possible association between the development of emphysema and occupational exposure to industrial pollutants has been studied. Based on complete work histories from the participants, the number of years of employment in a polluted workplace was assessed for 36 patients with emphysema and 72 referents, matched for age (+/- 2 a) and smoking habits. Analyzed as matched triplets, the estimated risk ratio for the exposed (greater than or equal to 10 a in polluted workplaces) subjects developing emphysema in comparison to the nonexposed (less than 10 a in polluted workplaces) was 3.0, a value statistically significant. Estimated risk ratios according to the number of years employed in a polluted workplace did not show any significant trend towards a dose-response relationship. Only one of the emphysema patients had never smoked. In the further study of the relationship between emphysema and occupational exposure, the interaction between cigarette smoke and different occupational exposures seems to be of particular interest.

Key terms case-referent study; emphysema; industrial pollutant; occupational exposure; smoking habit