Weiss T, Hardt J, Angerer J
Institute and Outpatient Clinic of Occupational, Social and Environmental Medicine, Erlangen, Germany.
J Chromatogr B Biomed Sci Appl. 1999 Apr 16;726(1-2):85-94. doi: 10.1016/s0378-4347(99)00034-1.
This is a newly developed method which permits the quantitative determination of 2-thiazolidinethione-4-carboxylic acid (TTCA, an established biomarker of exposure to CS2) as a metabolite of alkylene bisdithiocarbamates (ABDCs) in human urine. After separation of TTCA from the urinary matrix using liquid-liquid extraction the analyte was converted into its diethyl derivative. Separation and quantitative analysis was carried out by capillary gas chromatography and mass selective detection in single ion monitoring mode. 4-(4-Chloro-2-methylphenoxy)butanoic acid (MCPBA) served as internal standard. The detection limit was 0.7 microg/l in urine. The relative standard deviation of the within-series imprecision was 4.3% at a concentration of 13 microg/l. The relative recovery was within the range of 86 to 98%. In order to determine the suitability of TTCA for biological monitoring after exposure to ABDCs, we analysed 87 24-h urine samples from occupationally exposed workers. The results were compared with the levels of TTCA excreted in urine by 50 control persons without known exposure to dithiocarbamates or CS2. This collective of unexposed persons also provided TTCA reference values for the general population. The urinary TTCA concentrations of the exposed persons were in the range from 0.8 microg/g creatinine to 515 microg/g creatinine. Unexposed persons excreted TTCA in concentrations from below the detection limit to 182 microg/g creatinine. The median concentration found in exposed persons (27 microg/g) was nearly 2.5 times higher than in non-exposed persons (11 microg/g). The difference between the exposed and unexposed collective was highly significant. Assessment of an individual's exposure by determining the level of TTCA in urine nevertheless was not possible. This was due to the relatively wide range of concentrations and because the ranges of both collectives overlapped.
这是一种新开发的方法，可用于定量测定人尿中作为亚烷基双二硫代氨基甲酸盐（ABDCs）代谢产物的2-噻唑烷硫酮-4-羧酸（TTCA，一种已确定的二硫化碳暴露生物标志物）。使用液-液萃取从尿液基质中分离出TTCA后，将分析物转化为其二乙基衍生物。通过毛细管气相色谱法和单离子监测模式下的质量选择性检测进行分离和定量分析。4-(4-氯-2-甲基苯氧基)丁酸（MCPBA）用作内标。尿液中的检测限为0.7微克/升。在浓度为13微克/升时，系列内不精密度的相对标准偏差为4.3%。相对回收率在86%至98%范围内。为了确定TTCA在ABDCs暴露后进行生物监测的适用性，我们分析了87份职业暴露工人的24小时尿液样本。将结果与50名无二硫代氨基甲酸盐或二硫化碳已知暴露史的对照人员尿液中排出的TTCA水平进行了比较。这个未暴露人群组也提供了一般人群的TTCA参考值。暴露人员的尿TTCA浓度范围为0.8微克/克肌酐至515微克/克肌酐。未暴露人员排出的TTCA浓度范围为低于检测限至182微克/克肌酐。暴露人员中发现的中位数浓度（27微克/克）几乎是非暴露人员（11微克/克）的2.5倍。暴露组和未暴露组之间的差异非常显著。然而，通过测定尿液中TTCA水平来评估个体暴露情况是不可能的。这是由于浓度范围相对较宽，且两个组的范围有重叠。
