Objective: We conducted a repeated-measurement study to (1) investigate the correlation between occupational exposure to airborne acrylamide (AA) and the time-dependent behavior of urinary AAMA, GAMA2, and GAMA3 and (2) calculate the estimated biological exposure index at the permissible exposure limit (PEL) level of 30 μg/m(3).
Methods: Forty-four workers were recruited--8 were AA-exposed and 36 were controls. Pre- and post-shift urine samples were collected from the exposed group in parallel with personal sampling for 8 consecutive days and only 1 day for the control group and analyzed using liquid chromatography-electrospray ionization/tandem mass spectrometry (LC-ESI-MS/MS).
Results: Post-shift urinary AAMA level was significantly associated with personal AA exposure (p < 0.001), indicating that urinary AAMA was a better AA exposure biomarker. The estimated urinary excretion of AAMA was 3.0 mg/g creatinine for nonsmoking workers exposed to the PEL of 30 μg/m(3). The median GAMA (the sum of GAMA2 and GAMA3)/AAMA ratio for exposed workers was 0.03 (range, 0.005-0.14), relatively lower than that of the nonoccupational group.
Conclusions: Although sample size in this study was small, the repeated-measurement data provide useful reference for future studies related to biological monitoring of occupational exposure to AA.