中文摘要：

目的探讨环氧化物水解酶1（epoxidehydrolase1，EPHXl）基因多态性对苯乙烯体内代谢的影响。方法选择山东省某玻璃钢游艇生产企业喷漆车间工龄在1年以上，防护情况基本相同的全部工人（56人）作为研究对象。分别测定个体苯乙烯8h时间加权平均浓度（8h-TWA）、尿中代谢产物一苯乙醇酸（mandelicacid，MA）和苯乙醛酸（phenylglyoxylicacid，PGA）浓度，采用聚合酶链反应一限制性片段长度多态性（PCR—RFLP）法检测研究对象的EPHXl基因多态性。结果工人尿中MA浓度为（177．25±82．36）mg／gCr，PGA浓度为（145．91±69．73）mg／gCr，苯乙烯8h—TWA为（133．28±95．81）mg／m3。尿中MA及PGA浓度与苯乙烯8h—TWA均呈正相关关系（R：0．861，P〈0．05；R=0．868，P〈0．05）。按苯乙烯8h-TWA〉50mg／m。为高暴露组，8h-‘1wA≤50mg／m，为低暴露组，将研究对象分为高暴露组和低暴露组，高暴露组和低暴露组受试者携带高活力EPHXI基因型个体尿中的MA和PGA浓度明显高于携带EPHXl低活力组基因型者，差异有统计学意义（P《0．05）。结论EPHXI基因多态性对苯乙烯在体内的代谢过程可能有一定影响。

英文摘要：

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, respective- ly, and the 8 h-TWA of styrene was 133.28＋95.81 mg/m3. Urinary concentrations of MA and PGA were posi- tively 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/m3） and low-exposure group （8 h-TWA ~〈 50 rag/m3）, and in the two groups, the urinary concentrations of MA and PGA were significantly higher in the individuals carrying high-ac- tivity genotypes of EPHXI than in those carrying low-activity genotypes of EPHX1 （P〈0.05）. Conclusion Genetic polymorphisms of EPHX 1 play an important role in the metabolic process of styrene in vivo.