Urinary Excretion of Thioethers Related to Styrene Exposure

• Published in: Journal of Occupational Health Vol. 40; no. 4; pp. 350 - 355
• Main Authors: Truchon, Ginette, Bégin, Denis, Lesage, Jacques, Goldberg, Mark, Talbot, Diane, Drolet, Daniel, Gérin, Michel
• Format: Journal Article
• Language: English
• Published: Tokyo JAPAN SOCIETY FOR OCCUPATIONAL HEALTH 01-10-1998; John Wiley & Sons, Inc
• Subjects: Acids; Biological monitoring; Chromatography; Creatinine; Excretion; Gas chromatography; Global thioethers; High pressure; Liquid chromatography; Mass spectrometry; Occupational exposure; Occupational health; Styrene; Styrene exposure; Ultraviolet radiation; Urinary specific mercapturic acids
• ISSN: 1341-9145; 1348-9585; 1348-9585
• DOI: 10.1539/joh.40.350

The objective of this study was to test the suitability of styrene-specific mercapturic acids as urinary bioindicators of occupational styrene exposure. The excretion of mandelic acid (MA), global thioethers and styrene-specific mercapturic acids was measured in urine samples from 64 workers employed in three companies fabricating glass fiber-reinforced polyester products. Global thioethers were measured by a spectrophotometric method while MA and specific mercapturic acids, N-acetyl-S-(1-phenyl-2 hydroxyethyl)-L-cysteine (M1) and N-acetyl-S-(2-phenyl-2-hydroxyethyl)-L-cysteine (M2), were measured by high pressure liquid chromatography with UV detection. Excretion of M1 and M2 was qualitatively verified by gas chromatography-mass spectrometry. The environmental measurements were carried out with passive dosimeters. Workers had 8-h TWA exposure levels ranging from 0 to 667 mg/m^3 . End-of-shift MA excretion ranged from 0 to 2.08 mmol/mmol creatinine and was well correlated with environmental styrene exposure (r=0.91, p<0.001). M1 and M2 were detected (i.e. above ca. 1 μmol/mmol creatinine) in urine samples of only three workers who were exposed to various concentrations of styrene. End-of-shift excretion of global thioethers was found to be significantly correlated to cigarette consumption as well as to styrene exposure, as measured by end-of-shift MA excretion. In opposition to data from rats, our results indicate that humans exposed to styrene excrete little styrene-specific thioethers. The apparent inter-individual variability in excretion of M1 and M2 suggests that they may not constitute suitable indicators of occupational styrene exposure.