[Influence of genetic polymorphisms of epoxide hydrolase 1 on metabolism of styrene in body].
OBJECTIVE
To investigate the role of genetic polymorphisms of epoxide hydrolase 1 (EPHX1) in the metabolism of styrene in vivo.


METHODS
Fifty-six styrene-exposed workers, who worked in the painting workshop of an enterprise for manufacturing glass fiber-reinforced plastic yachts in Shandong Province, China for over one year and were protected in approximately the same way, were selected as study subjects. The 8-hour time-weighted average concentration (8 h-TWA) of styrene and the concentrations of mandelic acid (MA) and phenyl glyoxylic acid (PGA) as urinary metabolites were measured. The genetic polymorphisms of EPHX1 were detected by polymerase chain reaction-restriction fragment length polymorphism analysis.


RESULTS
The urinary concentrations of MA and PGA were 177.25±82.36 mg/g Cr and 145.91±69.73 mg/g Cr, respectively, and the 8 h-TWA of styrene was 133.28±95.81 mg/m3. Urinary concentrations of MA and PGA were positively correlated with 8 h-TWA of styrene (R=0.861, P < 0.05; R=0.868, P < 0.05). The subjects were divided into high-exposure group (8 h-TWA >50 mg/m(3)) and low-exposure group (8 h-TWA ≤ 50 mg/m(3), and in the two groups, the urinary concentrations of MA and PGA were significantly higher in the individuals carrying high-activity genotypes of EPHX1 than in those carrying low-activity genotypes of EPHX1 (P < 0.05).


CONCLUSIONS
Genetic polymorphisms of EPHX1 play an important role in the metabolic process of styrene in vivo.
Shandong Academy of Occupational Health and Occupational Medicine, Jinan 250062, China.
Fang
F
Zhang
Jin-long
JL
Meng
Hua
H
Shao
Zhi-hu
ZH
Zhang
Bin
B
Feng
D000328:Adult; D000395:Air Pollutants, Occupational / Q000493:pharmacokinetics*; D002681:China; D004851:Epoxide Hydrolases / Q000235:genetics*; D006038:Glyoxylates / Q000652:urine; D006801:Humans; D008297:Male; D008333:Mandelic Acids / Q000652:urine; D016273:Occupational Exposure; D011110:Polymorphism, Genetic; D020058:Styrene / Q000493:pharmacokinetics*
D000395:Air Pollutants, Occupational; D006038:Glyoxylates; D008333:Mandelic Acids; C012482:phenylglyoxylic acid; D020058:Styrene; D004851:Epoxide Hydrolases; C522330:EPHX1 protein, human; C037938:mandelic acid