A mortality study among workers in an English asbestos factory

Area of Science:

• Occupational Health
• Epidemiology
• Environmental Health

Background:

• A prior study (Knox et al., 1968) examined asbestos textile workers, finding minimal increased mortality post-1932 regulations.
• The earlier study noted that carcinogenic effects of asbestos might take 20 years to manifest, limiting initial conclusions.

Purpose of the Study:

• To assess long-term asbestos-related disease risk in workers exposed after 1933.
• To compare disease incidence in workers exposed before and after the first Asbestos Industry Regulation (1931).

Main Methods:

• Cohort study design.
• Extended follow-up of 963 workers first exposed in 1933 or later.
• Analysis of mortality data for lung cancer, non-malignant respiratory disease, and pleural mesothelioma.

Main Results:

• Increased mortality observed for carcinoma of the bronchus (31 deaths vs. 19.3 expected).
• Elevated mortality for non-malignant respiratory disease (35 deaths vs. 25.0 expected).
• Five deaths attributed to pleural mesothelioma in the post-1933 exposure group.

Conclusions:

• Asbestos exposure after 1933 regulations is associated with increased risk of lung cancer and respiratory diseases.
• The risk of asbestos-related diseases is significantly lower compared to workers exposed before 1933.
• Even with regulations, asbestos exposure poses a continued, albeit reduced, health risk.