目的 利用高效率液相層析儀同步分析石化員工尿中苯代謝物，包括hydroquinone (HQ)、catechol (CAT)、muconic acid (MA)和phenol(PH)之濃度。方法 收集312名石化工廠作業員工之尿液中苯代謝物，利用高效率液相層析儀分析苯之代謝物，此方法之偵測極限HQ、MQ、CA及PH分別為2.46 ng、0.13 ng、2.34 ng及9.69 ng。結果 三種高低不同苯代謝物濃度之變異性（CV值）均低於8%。除phenol外，在4℃及-20℃中持續，28天均十分安定，平均四種尿中生物偵測回收率在HQ：101.5%, CAT：102.9% , MQ：103.9%及PH：107.5%。測定石化員工尿中苯代謝物以phenol濃度最高，其次為CAT、HQ，而以MA濃度最低，利用多變項迴歸分析得知吸菸者有較高HQ及CAT之濃度，苯暴露組之CAT濃度也有統計之差異，其它變項並無統計上之差異。結論 本研究對象暴露苯代謝物之濃度相對偏低，此與作業環境中苯濃度較低有關，此研究結果可提供同時分析四種苯代謝物可靠及偵測方法參考。
Purpose. To determine the benzene metabolites in urine, including hydroquinone (HQ), catechol (CAT), muconic acid (MA) and phenol (PH) by high-performance liquid chromatography (HPLC). Methods. Urinary concentrations of these four benzene metabolites in 312 petrochemical plant workers were measured by HPLC. The limits of detection were 2.46 ng for HQ, 0.13 ng for MA, 2.34 ng for CAT and 9.69 ng for PH. Results. Reproducibility was tested at three concentrations (high, medium, low); the coefficient of variation (CV) was less than 8%. When PH was excluded, CV was 5%. Stability was tested at 4℃ and -20℃ over a period of 28 days. Stability of all four benzene metabolites was higher at -20℃ than at 4℃. Overall, there was a decline in stability over time with phenol being the least stable (40% at 28 days). Average recoveries were as follows: HQ=101.5%, CAT=102.9%, MA=103.9%, PH=107.5%. Urinary PH concentrations were highest, followed by CAT, HQ and MA. Multiple regression analysis revealed that levels of the urinary benzene metabolites were affected by smoking and exposure to benzene increased urinary CAT concentrations. Conclusions Petrochemical workers exposed to low-level benzene in petrochemical factories had slightly lower levels of benzene metabolites in urine compared with previous studies. Our findings showed that HPLC is a reliable and convenient method for the simultaneous determination of benzene metabolites in urine among workers exposed to low concentrations of benzene.
