职业性苯暴露反-反式粘糠酸生物接触限值研究

目的研究职业性苯暴露反．反式粘糠酸（t，t—MA）生物接触限值。方法实验室建立生产环境空气中苯浓度的气相色谱检测方法及作业工人尿中t，t—MA含量的高效液相色谱检测方法，并通过检测苯暴露现场工人8h苯暴露水平及班前、班后尿中t，t．MA含量，研究其相关性。结果苯暴露者班前、班后尿中t，t—MA含量与其苯暴露水平有明显的相关关系。班前y（mg／gCr）=0．924＋0．108X（me／m^3），r=0．62，P〈0．01；班后y（mg／gCr）=2．103＋0．177X（mg／m^3），r=0．791，P〈0．01。结论根据我国作业场所空气中苯的国家卫生标准，按回归方程推导出职业接触苯生物接触限值，推荐职业暴露苯的生物接触限值为工作班班后尿t，t．MA含量为3．0mg／gCr，下一班班前尿t，t．MA含量为1．5mg／gGr。

Studies on biological limit of urine trans, trans-muconic acid for occupational exposure to benzene

Objective To study the biological limit of urine trans,trans-muconic acid(t,t-MA)for occupational exposure to benzene.Method Lab oratory methods for examining benzene in workplace air and urine level of t,t-MA in workers exposed to benzene were established by gas chromatograph and high performance liquid chromatograph.Level of exposure to benzene was evaluated by examining urine levels of t,t-MA during eight-hour work,before and after shift in workers exposed to benzene in a factory.Relationship between level of exposure to benzene and urine level of t,t-MA in workers was analyzed.Result Urine level of t,t-MA in workers(exposed) to benzene closely related to their exposure level.There was a close relationship between urine level of t,t-MA and level of exposure to benzene before and after shift in the workers,with regression equations and correlation coefficients of Y(mg/gCr)=0.924+0.108X(mg/m~3)and r=0.62(P<0.01)and Y(mg/gCr)=2.103+0.177X(mg/m~3)and r=0.791(P<0.01),respectively.Conclusion According to the national hygienic standard for benzene in workplace air,the biological limit of urine level of t,t-MA could be calculated as follows for recommended occupational exposure to benzene:3.0 mg/gCr and 1.5 mg/gCr for workers exposed to benzene after and before shift,respectively.