Urinary t,t-muconic acid as an indicator of exposure to benzene.
A method for rapidly determining t,t-muconic acid (MA) by high performance liquid chromatography was developed and successfully applied to urine samples from 152 workers exposed to benzene (64 men, 88 women) and 213 non-exposed controls (113 men, 100 women). The MA concentrations in urine correlated linearly with time weighted average benzene concentrations in the breath zone air of workers. A cross sectional balance study showed that about 2% of benzene inhaled is excreted into the urine as MA. The MA concentrations in the urine of the non-exposed was below the detection limit (less than 0.1 mg/l) in most cases, and the 95% lower confidence limit of MA for those exposed to benzene at 5 ppm (5.0 mg/l as a non-corrected value) was higher than the 97.5%-tile values for the non-exposed (1.4 mg/l). In practice, it was possible to separate those exposed to 6-7 ppm benzene from the non-exposed by means of urine analysis for MA. The urinary MA concentration was suppressed by coexposure to toluene.
Inoue
O
O
Department of Environmental Health, Tohoku University School of Medicine, Sendai, Japan.
Seiji
K
K
Nakatsuka
H
H
Watanabe
T
T
Yin
S N
SN
Li
G L
GL
Cai
S X
SX
Jin
C
C
Ikeda
M
M
D000395:Air Pollutants, Occupational / Q000032:analysis; D001554:Benzene / Q000378:metabolism* / Q000494:pharmacology; D002851:Chromatography, High Pressure Liquid; D003020:Clothing; D004781:Environmental Exposure; D005231:Fatty Acids, Unsaturated / Q000652:urine*; D005260:Female; D006801:Humans; D008297:Male; D010150:Paint; D013011:Sorbic Acid / Q000031:analogs & derivatives / Q000652:urine*; D014050:Toluene / Q000378:metabolism / Q000494:pharmacology
D000395:Air Pollutants, Occupational; D005231:Fatty Acids, Unsaturated; D014050:Toluene; C005939:muconic acid; D001554:Benzene; D013011:Sorbic Acid