Application of the New Asthma-Specific Job Exposure Matrix: A Study in Quebec Apprentice Cohort Exposed to Isocyanates

Background: Recently, the first asthma-specific Job Exposure Matrix (JEM) was updated to occupational JEM (OAsJEM). Our study aimed evaluate association between continued exposure isocyanates and incident work-related chest symptoms in former car-painting apprentices compare associations using new OAsJEMs.Methods: We used data from an inception cohort of male apprentices. Post-apprenticeship isocyanate during follow-up evaluated (“exposed”=1 or “not exposed”=0) OAsJEM (high=2, medium=1, none=0). Association occupation incidence rhinoconjunctival were through cox regression models, adjusted for age, smoking, wheezing, non-specific bronchial hyperresponsiveness. Results: The agreement two JEMs (exposed vs non-exposed isocyanate) perfect (kappa coefficient=0.946, p<0.001). There only five subjects who classified as based on JEM, but had a medium OAsJEM. increased risk high-exposure category (hazard ratio [HR] 2.7, 95% CI 1.1 – 6.6) (HR 2.9, 0.3 30.0) compared reference group OAsJEM, whereas HR 2.5 (95% 1.0-6.2) observed JEM. Both yielded inconclusive rhino-conjunctivitis. Conclusion: consistently showed that symptoms.