Study of risk factors for atopic sensitization, asthma, and bronchial hyperresponsiveness in animal laboratory workers

OBJECTIVES The aim of this estudy was to investigate the influence of allergen exposure levels and other risk factors for allergic sensitization, asthma, and bronchial hyperresponsiveness (BHR) in workers exposed to laboratory animals. METHODS This was a cross-sectional study performed at two universities, 123 workplaces with 737 subjects. Dust samples were collected from laboratories and animal facilities housing rats, mice, guinea pigs, rabbits, or hamsters and analyzed by enzyme-linked immunosorbent assay (ELISA) to measure allergen concentrations. We also sampled workplaces without animals. Asthma was defined by both symptoms and BHR to mannitol. The concentrations of allergens were tested for association with a skin prick test, respiratory symptoms, spirometry data, and BHR. This multivariate analysis was performed by using Poisson regression to estimate the relative risk (RR) for the exposed group. RESULTS Our sample comprised students and workers, with 336 subjects in the nonexposed group and 401 subjects in the exposed group. Sixty-nine subjects (17%) had positive results in the skin prick test for animal allergens in the exposed group; in the nonexposed group, 10 subjects had positive results (3%) (p