Change in prevalence of asbestos-related disease among sheet metal workers 1986 to 2016

A medical screening program began in 1986 for sheet metal workers exposed to asbestos, primarily while working alongside insulators applying spray-on asbestos materials, a practice banned in 1973. Exposure continues during maintenance, renovation, and repair.

Radiographic abnormalities among 26 397 sheet metal workers examined from 1986 to 2016 were analyzed by year of entry into the trade. Logistic regression was used to examine risk factors for parenchymal and pleural abnormalities among the overall study population and among the subcohort who entered the trade after 1973.

Prevalence of parenchymal disease was 17.4% for those starting work before 1950 compared with 0.8% for those starting work after 1973 (adjusted prevalence odds ratio [pOR] = 26.65, 95% confidence interval [CI] = 18.46-38.46). For each calendar year after 1973, entering the trade 1 year later was associated with an estimated 12.7% decreased odds of acquiring asbestos-related disease (adjusted pOR = 0.873, 95% CI = 0.832-0.916).

Sheet metal workers who began work after the US implemented environmental and occupational regulations develop asbestos-related disease at much reduced rates, consistent with regulatory projections made for nonmalignant asbestos-related disease by the Occupational Safety and Health Administration at the time. Cancer remains a concern among this cohort, and lung cancer screening recommendations should consider year of entry into the trade. This study highlights the importance of regulatory intervention and of continued surveillance.