RF-112 Asbestos-related disease in the Ontario Asbestos Workers Register

Objectives Research on asbestos-related disease (ARD) has traditionally focused on groups with well-recognized, consistently high exposure. Contemporary exposure to asbestos occurs more intermittently, for example during maintenance of asbestos-containing materials (ACM). The Ontario Asbestos Workers Register (AWR) was established in 1986 to track asbestos exposure. This study reports on the risk of ARD among workers in the AWR. Methods Overall 33,490 AWR registrants were included. Data were linked probabilistically with administrative health databases (1986–2018) to identify cases of ARD. Workers were followed until diagnosis, death, age 100, last contact with the health system, or end of study, whichever occurred first. Incidence rates were compared to the general population using standardized incidence ratios (SIRs). Associations between ACM exposure and ARD were estimated using Poisson regression. Results Overall 26,401(79%) AWR registrants were linked to health data; 97% were male. The mean age at cohort entry was 36 years. The most common industries represented were construction (61%), manufacturing (20%) and education (10%). Among men and women rates were markedly increased for mesothelioma [M:SIR 6.55(95% CI=5.34–7.96); W:SIR 19.3(3.87–56.3)] and pulmonary fibrosis [M:SIR 13.8(11.9–15.9); W:SIR 9.15(2.46–23.4)]. The risk of asbestosis was also elevated, but did not reach statistical significance among women [M:SIR 11.1(9.46–12.9); W:SIR 1.21(0.02–6.75)]. Among men and women, rates of COPD and lung cancer were elevated, but few cases were observed among women. Compared to workers with 238 hours had increased rates of lung cancer [RR 1.3(1.07–1.57)], mesothelioma [RR 3.13(1.94–5.06)], asbestosis [RR 3.31(2.33–4.71)], COPD [RR 1.34(1.22–1.48)], and pulmonary fibrosis [RR 1.86(1.34–2.58)]. Conclusion Exposure to asbestos in construction and building maintenance continues to contribute to ARD incidence. Though a Canadian ban on asbestos use in new products is encouraging, it is likely to have minimal impact on ARD resulting from construction activities, where exposure to existing ACM will persist.