Asbestosis is a chronic lung disease caused by inhalation of asbestos fibers. Exposure to these fibers can cause lung tissue scarring and shortness of breath. Asbestosis can develop many decades after exposure to asbestos.
Risk factors
Construction workers, such as insulators, electricians, and plumbers are several occupations that have experienced high rates of this condition. Metal workers and platers and boilermakers are also at an increased risk of asbestosis.
The greatest risks of asbestosis were observed among workers employed in construction and some manufacturing industries.
Asbestos-containing materials, particular insulation, were widely used in pre-1990 construction in Canada, and is still present in many older homes and buildings [2]. Insulators, plumbers, electricians, and other construction trades workers may frequently handle or work near asbestos-containing materials during building maintenance and renovation.
The non-metallic mineral products industry includes establishments engaged in manufacturing clay, cement and concrete, glass and glass products, and historically, asbestos and vermiculite products. The latter manufacturers are captured in the miscellaneous non-metallic mineral products industries, where the highest asbestosis risk was observed.
Asbestos was commonly used as an insulating material in some hot metalworking processes [3]. Primary metal industry workers may operate furnaces and other heating apparatuses insulated with asbestos. When these materials are disturbed or degrade, asbestos fibres can be released into the air.
Mechanics work on maintenance and repair of machinery and vehicles, which often involves removing parts for cleaning or replacement. Asbestos was widely used in auto parts, such as brake pads, clutches, and hoodliners, and may be present in older vehicles and machinery [4,5].
Increased AMI risk was observed among workers in the ODSS employed in rubber and plastic products fabrication. Plastic stabilizers frequently include cadmium, which has been posited to increase AMI risk through atherosclerosis [21]. A cohort study of British rubber factory workers found increased risk of cardiovascular deaths associated with exposure to N-nitrosomorpholine, rubber dust, rubber fumes and N-nitrosamines sum [22].
Excess AMI risk was detected in the ODSS for a variety of occupation groups, which likely reflects the numerous risk factors for cardiovascular disease including both workplace and lifestyle factors.
For more details: Troke, N, Logar‐Henderson, C, DeBono, N, et al. Incidence of acute myocardial infarction in the workforce: findings from the Occupational Disease Surveillance System. Am J Ind Med. 2021; 1– 20.
Figure 1. Risk of asbestosis diagnosis among workers employed in each industry group relative to all others, Occupational Disease Surveillance System (ODSS), 1999-2016
The hazard ratio is an estimate of the average time to diagnosis among workers in each industry/occupation group divided by that in all others during the study period. Hazard ratios above 1.00 indicate a greater risk of disease in a given group compared to all others. Estimates are adjusted for birth year and sex. The width of the 95% Confidence Interval (CI) is based on the number of cases in each group (more cases narrows the interval).
Figure 2. Risk of asbestosis diagnosis among workers employed in each occupation group relative to all others, Occupational Disease Surveillance System (ODSS), 1999-2016
Table 1. Surveillance of Asbestosis: Number of cases, workers employed, and hazard ratios in each industry (SIC)
Table 2. Surveillance of Asbestosis: Number of cases, workers employed, and hazard ratios in each occupation (CCDO) group
Figure 1. Crude incidence rate of asbestosis among males in the ODSS, 2000-2014 (n=1.76 million)
The crude incidence rate is the number of cases of disease diagnosed per person per year of follow-up in the ODSS cohort. The age-standardized incidence rate is the rate we would observe if we removed the influence of aging in the cohort over time. The general population of males in Ontario in 1995 was used as the standard. All rates are expressed per 100,000 persons per year.
Figure 2. Age-standardized incidence rate of asbestosis among males in the ODSS, 2000-2014 (n=1.76 million)
Please note that ODSS results shown here may differ from those previously published or presented. This may occur due to changes in case definitions, methodological approaches, and the ongoing nature of the surveillance cohort.
