Increased risk of asthma among Finnish construction workers.

AIM To determine the risk of asthma among 7891 Finnish construction workers in the Pirkanmaa Region of southern Finland. METHOD Retrospective cohort study of hospital records of the Tampere University Hospital. A population of Pirkanmaa paper mill workers (n=2686) and the Pirkanmaa working age population (n=252,500) served as reference populations. RESULTS There were 147 new cases of asthma among the construction workers in 1991-1995. The annual rate was 37 per 10,000 workers and the odds ratio was 2.1 [95% confidence interval (CI)=1.2-3.6] for the women and 1.8 (95% CI=1.5-2.2) for the men when compared with the general working age population. In general, the risk of asthma among the paper mill workers did not differ from the risk of asthma among the general working age population. The construction workers had an increased risk for asthma, although the number of reported cases of occupational asthma was lower for the construction workers than for the paper mill workers or for the working population. CONCLUSION Construction work, especially dusty tasks, was associated with an elevated risk of asthma. Thus the effect of exposure to irritant agents may have a role in the development of asthma among construction workers. For the most part, these cases of asthma do not meet the criteria for occupational asthma because the specified causal agent can not be defined. The aetiologic agents and mechanisms of asthma in construction work should be clarified for preventive measures.