Results: The most frequently exposed occupations in our study population were in construction, timber and furniture
making industries. We found increased risks of lung cancer for substantial cumulative exposure to wood dust in Study I
with cancer controls, (OR = 1.4: 95% confidence interval 1.0;-2.0) and in Study II (OR = 1.7: 95% confidence interval
1.1-2.7). There were no excess risks of lung cancer in any of the three datasets among workers whose cumulative
exposure was not substantial. These tendencies held equally within strata of low smokers and heavy smokers.