Background: There is evidence that occupational exposures increase the risk of developing asthma. We investigated potential relation between occupational exposures and asthma control among adults from Finland.

Methods: This was a population-based cross-sectional Northern Finnish Asthma Study (NoFAS), in which altogether 1995 adult subjects 17-73 years old living in Northern Finland answered the NoFAS questionnaire. Exposure was assessed based on questionnaire -reported occupational exposure to dusts or fumes. The outcome was asthma control measured with the Asthma Control Test (ACT) based on its five items, the total value ranging from 25 (best control) to 5. As statistical methods we applied Poisson regression.

Results: The mean ACT among women with no reported specific occupational exposure was 20.64 and among men this mean ACT was 20.59. Reported occupational exposures to strong scents and construction dust were related to significantly reduced ACT score among both women and men. Among women, other occupational exposures that were related to significantly reduced ACT score included glues, mold dust, cleaning chemicals, and other occupational chemicals. Among men, exposure at work to air pollutants was related to significantly reduced ACT score. Other occupational exposures related to reduced ACT level among men included flour and grain dust, paint and varnish, mold dust and wood dust.

Conclusions: Occupational exposures to several dusts and fumes are related to significantly reduced asthma control among both women and men, some were present only in men or women. Advice on protection against these identified occupational exposures should be included as an important part of asthma management for adults.