Incidence of occupational asthma by occupation and industry in Finland

BACKGROUND: Systematic research on occupation or industry-specific incidence of occupational asthma (OA) is sparse. We calculated the incidence of notified OA by occupation, industry and causative agent in Finland for the years 1989-95. METHODS: The numbers of cases of reported OA were retrieved from the Finnish Registry of Occupational Diseases for the population between 20 and 64 years of age. The numbers of employed workers were retrieved from Statistics Finland. Incidence rates were calculated for each occupation, industry and the total workforce. RESULTS: Altogether 2602 cases of OA were notified and the mean annual incidence rate was 17.4 cases/100,000 employed workers. The incidence rate was the highest in bakers, other painters and lacquerers, veterinary surgeons, chemical workers, farmers, animal husbandry workers, other food manufacturing workers, welders, plastic product workers, butchers and sausage makers, and floor layers. Cases caused by animal epithelia, hairs and secretions or flours, grains, and fodders accounted for 60% of the total. CONCLUSIONS: Estimation of occupation and industry-specific incidence rates forms the basis for successful prevention of OA, but necessitates collection of data over several years from well-established surveillance systems.