Exposure to terpenes: effects on pulmonary function.

Forty-eight subjects exposed to terpenes (mean air concentration 258 mg m-3) and 47 unexposed subjects, all employed at sawmills, were studied with regard to symptoms and pulmonary function. Dyspnoea and chest oppression were significantly increased in the exposed subjects compared to the unexposed controls. A reduced FEV1, on spirometry and an increased CV% and slope of the alveolar plateau (phase III) on single breath nitrogen washout were seen on Monday morning before exposure to terpenes. There was no correlation between exposure time (duration of employment) and lung function impairment. A day of industrial exposure to terpenes caused no further change in any lung function variable. The unexposed controls showed normal spirometry and nitrogen washouts. The findings indicate a slight stable lung function impairment of an obstructive nature which does not necessarily undergo further deterioration with increased duration of exposure.