Context: Few epidemiological studies have examined the relationship between chronic respiratory symptoms and exposure to environmental tobacco smoke (ETS) at work in adults, and none have shown clear dose-response relationships.
Objective: To examine the respiratory effects of ETS exposure at home and at work among never-smoking adults.
Design, setting, and participants: Cross-sectional, self-administered questionnaire survey conducted in December 1995 and January 1996 among 4468 male and 728 female police officers in Hong Kong who were never-smokers.
Main outcome measures: Respiratory symptoms and physician consultation in the previous 14 days for such symptoms by presence and amount of ETS exposure at work.
Results: Eighty percent of both men and women reported ETS exposure at work. Significant odds ratios (ORs) for respiratory symptoms were found among men with ETS exposure at work (for any respiratory symptoms, difference in absolute rate, 20.4%; OR, 2.33; 95% confidence interval [CI], 1.97-2.75; attributable risk, 57%) and physician consultation (difference in absolute rate, 4.5%; OR, 1.30; 95% CI, 1. 05-1.61; attributable risk, 23%). Trends were similar among women for any respiratory symptoms (difference in absolute rate, 15.4%; OR, 1.63; 95% CI, 1.04-2.56; attributable risk, 39%) and for physician consultation (difference in absolute rates, 2.8%; OR, 1.45; 95% CI, 0.87-2.41; attributable risk, 31%). Positive dose-response relationships with number of coworkers smoking nearby and amount of ETS exposure in the work place were found.
Conclusions: This study provides further evidence of the serious health hazards associated with ETS exposure at work. The findings support a ban on smoking in the workplace to protect all workers in both developed and developing countries. JAMA. 2000;284:756-763