Partition coefficients for the trihalomethanes among blood, urine, water, milk and air
Partition coefficients for the trihalomethanes among blood, urine, water, milk and air
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DOI：
10.1016/s0048-9697(01)00890-7
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发表时间：
2002-02-04
影响因子：
9.8
通讯作者：
Franzblau, A
中科院分区：
文献类型：
--
作者：
Batterman, S;Zhang, L;Franzblau, A
氯仿、溴二氯甲烷、氯二溴甲烷和溴仿组成了三卤代甲烷，这是一组广泛存在的、温和亲油的化合物，来自水的氯化和其他来源。许多动物研究表明，这些化合物的慢性毒性和致癌性，最近的工作已经证明了摄入和吸入暴露途径的重要性。本研究基于在平衡条件下和37℃下进行的顶空-气相色谱分析结果，提出了描述四种THM生物隔室(空气、水、血液、牛奶、尿液)之间平衡的分配系数。计算的分配系数范围为：血/水2.92~4.14，牛奶/血1.54~2.85，血/尿3.41~4.93，最低为氯仿，最高为溴仿。人奶和牛奶都进行了测试，结果相似。可获得的母乳样本可能不能完全考虑脂肪含量的差异以及可能影响分配系数估计的其他因素。建议同时测量接触者的乳汁和血液，以确认实验室结果。使用本研究中测量的辛醇-空气分配系数和辛醇-水分配系数来预测分配系数。结果与文献估计的氯仿和氯二溴甲烷的液/气分配相似，但与基于疏水性和脂类含量的预测不同。得到的分配系数与分子结构(溴原子数)之间具有很高的相关性。发现了这些类似化学物质的物理性质(相对分子质量和沸点)。在人体内，THM的储存和代谢具有相对较快的清除率，所得到的分配系数可以帮助解释生物监测的结果，并预测化学物质的积累和转移的可能性，特别是通过应用基于生理的药代动力学模型。可以使用这两种模型中的任何一种来预测对潜在易感人群(例如哺乳婴儿)的TM暴露。(C)2002 Elsevier Science B.V.保留所有权利。
Chloroform, bromodichloromethane, chlorodibromomethane, and bromoform comprise the trihalomethanes, a group of widespread and mildly lipophilic compounds that result from water chlorination and other sources. Many animal studies show the chronic toxicity and carcinogenicity of these compounds, and recent work has demonstrated the importance of both ingestion and inhalation exposure pathways. This study presents partition coefficients describing the equilibrium among biological compartments (air, water, blood, milk, urine) for the four THMs based on results of headspace-gas chromatographic analyses performed under equilibrium conditions and at 37degreesC. The calculated partition coefficients ranged from 2.92 to 4.14 for blood/water, 1.54-2.85 for milk/blood, and 3.41-4.93 for blood/urine, with the lowest being chloroform and the highest being bromoform. Both human and cow milk were tested, with similar results. The available samples of human milk may not fully account for differences in lipid content and possibly other factors that affect estimates of partition coefficients. Simultaneous measurements of milk and blood in exposed individuals are suggested to confirm laboratory results. Partition coefficients are predicted using the octanol-air partition coefficient, also measured in this study, and the octanol-water partition coefficient. Results are similar to literature estimates for liquid/air partitioning of chloroform and chlorodibromomethane, but they differ from predictions based on hydrophobicity and lipid content. High correlations between the derived partitioned coefficients and the molecular structure (number of Br atoms.) and physical properties (molecular weight and boiling point) are found for these analogous chemicals. In humans, THMs are both stored and metabolized with relatively rapid clearance rates, The derived partition coefficients can help to interpret results of biological monitoring and predict the potential for the accumulation and transfer of chemicals, specifically by the application of physiologically-based pharmacokinetic models. THM exposures to potentially susceptible populations, e.g. nursing infants, can be predicted using either such models. (C) 2002 Elsevier Science B.V. All rights reserved.