Biological monitoring in occupational exposure to low levels of 1,3-butadiene

Exposure to 1,3-butadiene (BD), a probable carcinogen to humans, was investigated in two groups Of Subjects working in a petrochemical plant where BID is produced and used to prepare polymers: 42 occupationally exposed workers and 43 internal non-occupationally exposed controls. BD personal exposure was very low but significantly different in the two groups (median airborne BD 1.5 and 0.4 mug/m(3) in exposed and controls, respectively). Similarly, BD in blood and urine, but not in exhaled air, was higher in the exposed workers than in controls (blood BID 3.7 ng/l versus < 1.8 ng/l, urinary BD 2.4 ng/l versus < 1.0 ng/l). These three biomarkers correlated significantly with personal exposure (0.283 less than or equal to Pearson's r less than or equal to 0.383) and between them (0.780 less than or equal to r less than or equal to 0.896). Excretion of urinary mercapturic acids N-acetyl-S-(3,4-hydroxybutyl)-L-cysteine (MI), N-acetyl-S-(1-hydroxymethyl-2-propenyl)-L-cysteine and N-acetyl-S-(2-hydroxy-3-butenyl)-L-Cysteine (MII), chromosomal aberrations (CA), and sister chromatid exchanges (SCE) in peripheral blood lymphocytes were not influenced by occupational exposure. Our results show that unmetabolised BD in biological fluids, and particularly urinary BD, represents the biomarker of choice for assessing occupational exposure to low airborne concentrations of BD. (C) 2004 Elsevier Ireland Ltd. All rights reserved.