Terpene exposure and respiratory effects among sawmill workers.

Objectives: This study was performed to evaluate exposure to terpenes in sawmills and to study the acute effects on lung function and the respiratory tract of exposed laborers.

Methods: The relationships between personal exposure to sawing fumes, assessed by air sampling, and terpene metabolites in urine were studied. The association between exposure to terpenes and acute effects on lung function was studied for 48 workers. The reactivity to methacholine within the study population was investigated. Variation in acute subjective respiratory symptoms during a workshift was evaluated by interviewing the employees before and after work, following a standardized questionnaire.

Results: Personal exposure to terpenes in the sawmills was 11-158 mg. m-3. The correlation (correlation coefficient = 0.84) between exposure to alpha-pinene and the concentration of verbenols (metabolites from alpha-pinene) in urine was good. No acute effects on forced vital capacity or forced expiratory volume during 1 s were detected. A decrease in carbon monoxide lung diffusing capacity after a workshift was detected. Workers with > or = 5 years of sawmill employment showed a higher reactivity to methacholine than those with < 5 years. Eye irritation increased during a workday.

Conclusions: Personal exposure to monoterpenes during a workshift sometimes exceeds the present Swedish limit value. The results show that verbenols in urine can be used as a biological exposure index of sawing fumes. Exposure in sawmills can cause an acute decrease in diffusing capacity. Workers with < or = 5 years of employment showed increased bronchial reactivity.