RESUMO
OBJECTIVE: To study the biological exposure limit of 1,3-butadiene occupational exposure. METHODS: A total of 139 workers who exposed to 1,3-butadiene in a rubber plant was chosen as exposure group,and 45 workers without 1,3-butadiene exposure were chosen as control group by judgment sampling method. Gas chromatography-flame ionization detection method was used to detect the level of 1,3-butadiene in workplace air,and ultra-high performance liquid chromatography-tandem mass spectrometric was used to determine the level of urinary dihydroxybutyl mercapturic acid( DHBMA) in end-of-shift workers. The correlation between 1,3-butadiene level and urinary DHBMA level was analyzed.The biological limit of 1,3-butadiene occupational exposure was assessed. RESULTS: The range of concentration-time weighted average( C_(TWA)) of 1,3-butadiene was from 0. 004 to 7. 609 mg/m~3,the medium was 0. 253 mg/m~3 in the exposure group,while the level of urinary DHBMA was from 0. 171 to 4. 235 mg/g Cr,and the medium was 1. 220 mg/g Cr. The range of C_(TWA)of 1,3-butadiene was below detection limit in the control group. The level of urinary DHBMA was from 0. 157 to 1. 808 mg/g Cr,and the medium was 0. 627 mg/g Cr in the control group. The level of urinary DHBMA in the exposure group was higher than that of the control group( P < 0. 01). The level of urinary DHBMA( y) of workers was related to the level of 1,3-butadiene( x) of the workplace air in the exposure group( y = 0. 349 x + 1. 082,P < 0. 01).CONCLUSION: DHBMA in urine could be used as a biomarker for 1,3-butadiene exposure in workers. The recommended biological exposure limit of DHBMA is 2. 900 mg/g Cr.