Worker exposures to airborne dust, endotoxin and beta(1,3)-glucan in two New Zealand sawmills

Background Sawmill workers have an increased risk of developing occupationa l asthma and other respiratory symptoms. Wood dust and microorganism have b oth been suggested to play a role, but few studies have measured microbial exposure levels in sawmills. Methods The preliminary study reported int his parer assessed airborne dust , bacterial endotoxin and beta(1,3)-glucan reported in this parer assessed airborne dust, bacterial endotoxin and beta(1,3)-glucan levels in 37 sample s from two New Zealand sawmills. Results Nearly one-third of the measured dust levels exceeded 1 mg/m(3) and only one sample exceeded the legal limit of 5 mg/m(3). Endotoxin levels we re clearly elevated with 50% of all measured exposures above 50 EU/m(3) (ra nge: 7-588 EU/m3). beta(1,3)-glucan levels were comparable with levels meas ured in other industries where workers are exposed to organic dust. Workers in the planing department had the highest mean exposures to dust, endotoxi n and beta(1,3)-glucan. Dust levels were only weakly correlated with endoto xin and beta(1,3)-glucan levels. Conclusions Endotoxin exposures in sawmill workers are at levels sufficient to potentially contribute to the development of respiratory symptoms. More over measurement of dust exposure is a poor proxy for beta(1,3)-glucan and endotoxin exposure in sawmill workers. (C) 2000 Wiley-Liss, Inc.