PREVALENCE OF RESPIRATORY SYMPTOMS AND INCREASED SPECIFIC IGE LEVELS IN WEST-AFRICAN WORKERS EXPOSED TO ISOCYANATES

Respiratory symptoms and immunological effects from chronic exposure t o isocyanates (toluene diisocyanate) were studied in a cross survey of workers from West African factories producing paints and polyurethane foam. A questionnaire, a pulmonary function test immunoglobulin E (Ig E) levels, radioallergosorbent test (RAST) and an atmospheric sample t o quantify isocyanate exposures were carried out in the workplace for each worker. Ninety-six workers, of whom 44 had occupational isocyanat e-induced asthma, were included in the study. Twenty-four viral-infect ed subjects were excluded from the immunological study. Specific antib odies to isocyanates were detected in two of the symptomatic individua ls. This low proportion appeared to be a common feature of this diseas e. The prevalence of isocyanate-induced asthma in a West African worki ng population appears to be significant in the context of chronic huma n exposure, as current data are based on excessive acute exposure due to an accident as seen in India.