Prevalence of self-reported respiratory symptoms in workers exposed to isocyanates

Until now, no survey had been conducted to assess the prevalence of respira tory symptoms in a large population that had been occupationally exposed to isocyanates, compared with that in a control group. We performed such a su rvey, using questionnaires administered by occupational physicians. Overall , 1114 workers' questionnaires (585 exposed and 529 control) were analyzed. Exposed workers, primarily painters from small factories, reported signifi cantly (P < 0.05) more wheezing (8.6% vs 3.6%), more breathlessness with wh eezing (3.4% vs 0.6%) in the last year, and more rhinitis (33.1% vs 19.1%) than did control workers. A trend for more asthma (2.1% vs 0.8%; P less tha n or equal to 0.07) was also observed. Furthermore, 16.4%, 16.2% and 10.6% of exposed workers reported (respectively) cough, rhinitis, and chest tight ness when working in contact with isocyanates. We conclude that isocyanate- exposed workers demonstrate significantly higher prevalence rates of rhinit ic and asthmatic symptoms than do control subjects.