STUDIO DELL'IPERRESPONSIVITA BRONCHIALE ASPECIFICA IN UN GRUPPO DI LAVORATORI DI UN'INDUSTRIA DI CELLE FRIGORIFERE

36 workers employed in a refrigerator factory, divided into 3 groups at different levels of exposure to MDI, were submitted to anamnestic questionnaire, spirographic tests, aspecific bronchial provocation test with acetylcholine, and dosage of plasmatic immnoglobulins IgA, IgE, IgG, IgM. We found no statistically significant difference among the three groups for the prevalence of symptoms of asthma and chronic bronchitis, basal respiratory parameters and immunoglobulins plasmatic concentrations, whereas the percent of subjects with aspecific bronchial hyperreactivity was statistically significantly greater in the group of subjects exposed to higher concentration of MDI. This difference was not related to any other variable except the level of exposure. We suggest that the aspecific provocation test with acetylcholine may be useful in the monitoring of subjects exposed to the respiratory hazard of isocyanates.