Brashear W T, Bishop C T, Abbas R
ManTech Environmental Technology, Dayton, OH 45437-0009, USA.
J Anal Toxicol. 1997 Sep;21(5):330-4. doi: 10.1093/jat/21.5.330.
Trichloroethylene (TCE) has been identified as a widespread groundwater contaminant. Trichloroacetic acid (TCA) and dichloroacetic acid (DCA) are toxicologically relevant metabolites of TCE that produce tumors in B6C3F1 mice. A sensitive method for measuring these metabolites in plasma has been developed to obtain pharmacokinetic data from TCE exposure. This is particularly important because DCA is more potent at producing hepatoproliferative lesions than TCA. At present, it is unclear whether DCA is produced by humans. Existing gas chromatographic methods cannot detect DCA at low nanogram-per-milliliter levels. A Finnigan TSQ 700 mass spectrometer (MS) with electrospray ionization was used to measure TCA, DCA, and monochloroacetic acid (MCA) in plasma. The MS was operated in negative ion tandem MS mode. The limit of detection for TCA and DCA was 4 ng/ml, and the limit of detection for MCA was 25 ng/mL. Plasma samples from human subjects exposed to 100 ppm TCE for 4 h contained TCA at concentrations as high as 10 micrograms/mL. DCA concentrations were less than 5 ng/mL, and MCA was not detected (less than 25 ng/mL).
三氯乙烯（TCE）已被确认为一种广泛存在的地下水污染物。三氯乙酸（TCA）和二氯乙酸（DCA）是TCE的毒理学相关代谢产物，可在B6C3F1小鼠体内诱发肿瘤。已开发出一种灵敏的方法来测定血浆中的这些代谢产物，以获取TCE暴露后的药代动力学数据。这一点尤为重要，因为DCA在引发肝增生性病变方面比TCA更具效力。目前尚不清楚DCA是否由人体产生。现有的气相色谱方法无法检测到纳克每毫升水平的DCA。使用配备电喷雾电离的Finnigan TSQ 700质谱仪（MS）来测定血浆中的TCA、DCA和一氯乙酸（MCA）。该质谱仪以负离子串联质谱模式运行。TCA和DCA的检测限为4纳克/毫升，MCA的检测限为25纳克/毫升。暴露于100 ppm TCE 4小时的人体受试者的血浆样本中，TCA浓度高达10微克/毫升。DCA浓度低于5纳克/毫升，未检测到MCA（低于25纳克/毫升）。
