ACETONE EXCRETION INTO URINE OF WORKERS EXPOSED TO ACETONE IN ACETATEFIBER PLANTS

To develop a proper protocol for biological exposure monitoring of ace tone, we evaluated whether exposure to acetone on the previous day aff ects the biological monitoring value at the end of a work day. One hun dred and ten male workers exposed to acetone in three acetate fiber ma nufacturing plants were monitored using a liquid passive sampler on tw o consecutive working days after 2 days without exposure. Urine sample s were collected at the start of the workshift and the end of the shif t on both days for each subject. For ten exposed workers urine samples were collected approximately every 2 h during and after the first wor king day until the following morning. Acetone concentrations in urine (Cu) at the start of the first working day were 1.3 +/- 2.4 (range: ND -14.1) mg/l in nonexposed workers and 2.4 +/- 5.6 (range: ND-40.3) mg/ l in exposed workers. The urinary acetone concentration at the beginni ng of the second working day indicated that urinary levels of acetone do not decline to background level by the following morning when expos ure concentration exceeds 300 ppm. However, linear regression analysis demonstrated that the relationship between environmental exposure lev el and urine level was similar on the Ist day and the 2nd day. Thus, a lthough urine acetone levels did not return completely to baseline aft er high exposures, under the present exposure levels the exposure on t he previous day did not significantly affect urinary acetone at the en d of the workshift of the next day.