Prevention of Work-related Asthma: Study Search

Prevention LevelSecondary
Study Year2002
Molecular Weight of AgentLMW
Agent CategoryDiisocyanates
Specific AgentDiisocyanates
Occupation Workers in general population (Includes cohort reported by Tarlo, 1995)
Outcome/DiagnosisOccuaptional asthma
Activity Intervention Comparison of OA claims b/w 1980-1993 from disocyanate exposure, which has medical surveillance program (1983), versus OA claims from other exposures that do not have medical surveillance programs. Medical surveillance measures for isocyanates were introduced by legislation and consisted of pre-employment respiratory questionnaire, repeated respiratory questionnaires every 6 months, and spirometry at least on annual basis. Legislation also required monitoring of diisocyanate concentrations to maintain 8-hr time average concentrations of 5 ppb and short-term concentrations below 20 ppb.
Participation RateResearchers retrospectively reviewed new claims (n=844) for OA between 1980 and 1993 compensated by the Ontario Workplace Safety and Insurance Board
Intervention EffectivenessThe number of OA claims due to disocyanates increased from 9-15/year (1980-83) to 55-58/year (1988-90), and then decreased to 19-20/year (1992-93). In contrast, OA claims due to other causes increased followed by a plateau. The risk for hospital admissions was 50% less for OA due to disocayanates (p<0.003) than for OA due to other causes. Duration of exposure was also shorter for claims of OA due to diisocyanates (p=0.0001).
Page last reviewed: February 20, 2020