Terpene exposure and respiratory effects among workers in Swedish joinery shops

Objectives Exposure to monoterpenes (alpha-pinene, beta-pinene and Delta(3)-carene) in joinery shops was studied in Sweden during the processing of Scot's pine, and the acute respiratory effects among the employees were evaluated. Methods A cross-sectional study of 38 workers was carried out in 4 joinery shops. The investigation included personal air sampling of monoterpenes, biological monitoring of metabolites of alpha-pinene in the workers' urine, interviews following a standardized questionnaire, and dynamic spirometry. Results The personal exposure to monoterpenes in the joinery shops was 10-214 mg/m(3). The correlation (correlation coefficient = 0.69) between exposure to alpha-pinene and verbenols (metabolites from a-pinene) in urine was relatively good. No acute effects on forced viral capacity or forced expiratory volume during 1 s were detected. The workers had significantly reduced preshift lung function values when compared with the values of a local reference group, even when smokers and ex-smokers were excluded. Conclusions Personal exposure to the monoterpenes alpha-pinene, beta-pinene, and Delta(3)-carene in joinery shops may exceed the present Swedish occupational exposure limit of 150 mg/m(3) during the winter season when workroom air is commonly recirculated. The determination of metabolites of alpha-pinene (verbenols) in urine can be used as an index of exposure to fumes released during wood-treating processes. The results from the lung function tests indicate chronic rather than acute reactions in the airways. The fact that there were no major changes in lung function over a workshift indicates chronic reaction in the airways.