Occupational Exposure and New-onset Asthma

In the last decades there has been growing recognition of the importance of
adult-onset asthma induced by workplace exposures. More than 360 substances
have been identified as potential inducers of asthma. Of these flour,
isocyanates, latex, persulphate salts, aldehydes, animals, wood dusts, metals,
enzymes account for 50-90% of reported cases. Now in a large population-based
study among adults in northern Europe the relation between occupational
exposure and new-onset asthma was studied again.

The study comprised 13 284 subjects born between 1945 and 1973, who answered a
questionnaire 1989-1992 and again 1999-2001. Asthma was defined as "Asthma
diagnosed by a physician" with reported year of diagnose. Hazard ratios (HR),
for new-onset adult asthma during 1980-2000, were calculated using a modified
job-exposure matrix as well as high-risk occupations in Cox regression models.
The analyses were made separately for men and women and were also stratified
for atopy.

Results: During the observation period there were 429 subjects with new-onset
asthma with an asthma incidence of 1.3 cases per 1000 person-years for men and
2.4 for women. A significant increase in new-onset asthma was seen for men
exposed to plant-associated antigens, epoxy, diisocyanates and accidental peak
exposures to irritants. Both men and women exposed to cleaning agents had an
increased asthma risk. When stratifying for atopy an increased asthma risk were
seen in non-atopic men exposed to acrylates, epoxy compounds, diisocyanates and
accidental peak exposures to irritants. Population attributable risk for
occupational asthma was 14% for men and 7% for women.

Conclusions: This population-based study showed that men exposed to epoxy,
diisocyanates and acrylates had an increased risk of new-onset asthma.
Non-atopics seemed to be at higher risk than atopics, except for exposure to
high molecular weight agents. Increased asthma risks among cleaners, spray
painters, plumbers, and hairdressers were confirmed.

Further Information - Source: The Annals of Occupational Hygiene