Biological monitoring of trace chemicals in residential environments

目：病屋综合症是指在新建筑中居住或工作的人所遇到的各种健康影响，在日本正成为一个引人注目的问题。本研究试图为预测居住环境中化学品对健康的不良影响和制定预防措施做出贡献。今年我们重点开发了一种通过气相色谱-质谱联用（GC-MS）定量测定暴露于芳香族挥发性有机化合物（VOCs）如甲苯、二甲苯和苯乙烯的个体尿液中痕量代谢物的方法。方法：我们以尿中的马尿酸（HA）、邻甲基马尿酸、间甲基马尿酸和对甲基马尿酸为目标（o-、m-、p-MHA），以及扁桃酸（MA）和苯乙醛酸（PGA），分别是甲苯、二甲苯和苯乙烯的代谢物。通过加入苯甲酰亮氨酸作为内标物（LS.）制备研究样品，在酸性条件下用乙酸乙酯萃取。衍生物组合物 ...更多信息 然后用乙酸乙酯复溶，用配备DB-1毛细管柱的GC-MS鉴定。在初始柱温150℃下进行洗脱，以10℃/min的速率递增至250℃。定量分析以SIM模式操作，选择离子m/z 105用于HA，m/z 119用于MHA，m/z 107用于MA，m/z 105用于PGA。为了检测环境空气中相应的VOCs浓度，采用活性炭管采样进行VOCs采集。经二硫化碳洗脱后，用GC-MS分析样品。用GC-MS对这些化合物进行分离和洗脱，得到一个良好的峰，SIM模式检测限为40-450 pg，这些化合物的标准曲线具有良好的线性关系。马尿酸、MHA、MA和PGA均从新建筑工人的尿液中检出，其中VOCs（甲苯、二甲苯和苯乙烯）水平较高。由于膳食来源的HA也会影响其在尿液中的本底水平，因此不能成为微量甲苯暴露的尿液标志物。然而，MHA，MA和PGA可以用来评估低水平暴露于二甲苯和styrene.Conclusions：这种新开发的GC-MS方法显示出高灵敏度的测定尿代谢物的个人暴露于痕量水平的VOCs。目前的研究结果支持其有用的生物监测室内挥发性有机物的动物和人类。少

objective : Sick house syndrome, the diverse health effects encountered by people dwelling or working in the new construction, is becoming a noticeable problem in Japan. This study was attempted to make a contribution toward prediction of the adverse health effects of chemicals in residential environments and planning preventive measures. This year we focused on developing a method for quantitative determination of trace level metabolites in urine of individuals exposed to aromatic volatile organic compounds (VOCs) such as toluene, xylene, and styrene by gas chromatography coupled with mass spectrometry (GC-MS).Methods : We targeted of the urinary hippuric acid (HA), o-, m-, and p-methyl hippuric acids (o-, m-, p-MHA), and mandalic acid (MA) and phenylglyoxalic acid (PGA), metabolites of toluene, xylene, and styrene, respectively. Study samples were prepared by adding benzoylleucine as the internal standard (LS.), extracting with ethyl acetate under acid condition. The derivative compo … More unds were then reconstituted in ethyl acetate and identified by GC-MS equipped with DB-1 capillary column. Elution was carried out at initial column temperature 150℃ with an increment at a rate of 10℃/min up to 250℃. The quantitative analysis was operated in SIM mode, selecting the ion m/z 105 for HA, m/z 119 for MHA, m/z 107 for MA, and m/z 105 for PGA. In order to examine the corresponding concentrations of VOCs in ambient air, active sampling by charcoal tubes was used for VOCs collection. After elution with carbon disulfide, the samples were analyzed with GC-MS.Results and discussion : Six urinary metabolites and I.S. were separated and eluted with a good peak by GC-MS. The limits of detection were 40-450 pg by SIM mode and the calibration curves of these compounds were fairly linear. Hippuric acid, MHA, MA, and PGA were all detected from urine of workers working in the new buildings in which higher levels of VOCs (toluene, xylene, and styrene) were found. Since HA of dietary sources could also affect its background level in urine, it cannot become a urinary marker of exposure to trace toluene. However, MHA, MA, and PGA can be used to evaluate low-level exposure to xylene and styrene.Conclusions : This newly developed GC-MS method showed high sensitivity for determination of urinary metabolites of individuals exposed to trace level VOCs. The present results support its usefulness in biological monitoring of indoor VOCs for animals and humans. Less