Purpose: Machinists are exposed to many sensitizing and irritant substances, but no previous study has assessed the occurrence of clinically verified occupational diseases in an unselected large workforce of machinists. Our aim was to study the occurrence of clinically verified occupational respiratory and skin diseases cross-sectionally in a large sample of machinists in southern Finland.
Methods: A computer-assisted telephone interview on occupational exposures and health was carried out in a sample of 961 machining workers from 64 metalworking companies. Of these, 757 (79%) answered the interview. A total of 245 subjects reported work-related respiratory or skin symptoms and were invited to clinical examinations; 138 of these underwent a clinical interview and examination by an occupational health physician. On the basis of this examination, 32 subjects were further examined at the Finnish Institute of Occupational Health (FIOH) for occupational skin or respiratory diseases.
Results: One case of occupational asthma (OA) and seven cases of occupational dermatoses (OD) were diagnosed, giving a prevalence of 0.13% (95% CI 0-0.39) for OA, and 0.92% (95% CI 0.24-1.16) for OD. The OA was induced by the patient's own MWF. Additional five cases of newly diagnosed non-occupational asthma (0.79%, 95% CI = 0.16-1.42) were detected. No cases of occupational rhinitis or COPD were diagnosed. The dermatoses diagnoses consisted of four cases of allergic contact dermatitis and three cases of irritant contact dermatitis. The most common causes of the ODs were MWFs.
Conclusion: This large clinical study of machinists representing metalworking in South Finland showed a prevalence of 0.13% of OA and 0.92% of OD. This relatively low occurrence of occupational diseases may reflect the strict Finnish criteria for the diagnosis of these occupational diseases and the relatively good level of occupational hygiene in machining workshops in Finland. Reported respiratory and skin symptoms were common, and these milder conditions may be linked to irritant rather than sensitizing exposures.