Effects of PCB exposure on neuropsychological function in children.
Effects of PCB exposure on neuropsychological function in children.
复制标题
DOI：
10.1289/ehp.5461
复制
发表时间：
2003-03
影响因子：
10.4
通讯作者：
Rice, Deborah C
中科院分区：
文献类型：
--
作者：
Schantz, Susan L;Widholm, John J;Rice, Deborah C
在过去的十年中，多氯联苯（PCB）的定量分析方法的进步导致了同系物特定的分析程序的广泛可用性，以及土壤，空气，水，沉积物，食品和人体组织中的PCB同系物分布的大量数据已经成为可用。这些数据表明，环境介质和人体组织中的多氯联苯残留物可能与任何商用多氯联苯混合物并不十分相似，这取决于接触来源、通过食物链的生物累积以及多氯联苯在环境中的风化作用。与此同时，毒理学研究使人们日益认识到，不同类别的多氯联苯同系物具有不同的毒性。分析技术和毒理学知识方面的这些进展正开始影响风险评估过程。随着正在进行的PCB研究评估儿童神经行为结果的介质的数据公布，PCB对神经发育影响的证据权重正在增加。在台湾、密歇根州（美国）、纽约（美国）、荷兰、德国和法罗群岛进行的研究都报告了产前接触多氯联苯与婴儿或儿童认知功能测量之间的负相关性。德国的研究还报告了出生后多氯联苯暴露与幼儿期认知功能之间的负相关-这一结果在以前的研究中没有发现。只有一项在北卡罗来纳州（美国）发表的研究未能发现多氯联苯暴露与认知结果之间的关联。尽管事实上，最近的几项研究已经使用同源特定的分析技术，只有有限的尝试，以评估特定的PCB同源物或类同源物在介导神经发育结果的作用。从统计学的角度来看，试图确定个别同源物在调解结果的作用受到阻碍的事实，大多数个别同源物的浓度是高度相关的，彼此和总的多氯联苯。从毒理学的角度来看，这些努力受到以下事实的阻碍：人体组织中存在的许多多氯联苯同系物从未在实验室中进行过研究，其对神经系统产生影响的相对效力也是未知的。关于各种同源物或同源物类别的健康影响的更完整的信息将有助于做出更知情的科学和风险评估决定。
In the last decade advances in the analytic methods for quantification of polychlorinated biphenyls (PCBs) have resulted in widespread availability of congener-specific analysis procedures, and large amounts of data on PCB congener profiles in soil, air, water, sediments, foodstuffs, and human tissues have become available. These data have revealed that the PCB residues in environmental media and human tissues may not closely resemble any of the commercial PCB mixtures, depending on source of exposure, bioaccumulation through the food chain, and weathering of PCBs in the environment. At the same time, toxicological research has led to a growing awareness that different classes of PCB congeners have different profiles of toxicity. These advances in analytic techniques and toxicological knowledge are beginning to influence the risk assessment process. As the data from ongoing PCB studies assessing the mediators of neurobehavioral outcomes in children are published, the weight of evidence for PCB effects on neurodevelopment is growing. Studies in Taiwan, Michigan (USA), New York (USA), Holland, Germany, and the Faroe Islands have all reported negative associations between prenatal PCB exposure and measures of cognitive functioning in infancy or childhood. The German study also reported a negative association between postnatal PCB exposure and cognitive function in early childhood--a result that had not been found in previous studies. Only one published study in North Carolina (USA) has failed to find an association between PCB exposure and cognitive outcomes. Despite the fact that several more recent studies have used congener-specific analytic techniques, there have been only limited attempts to assess the role of specific PCB congeners or classes of congeners in mediating neurodevelopmental outcomes. From a statistical standpoint, attempts to determine the role of individual congeners in mediating outcomes are hampered by the fact that concentrations of most individual congeners are highly correlated with each other and with total PCBs. From a toxicological standpoint, these efforts are hampered by the fact that many of the PCB congeners present in human tissues have never been studied in the laboratory, and their relative potency to produce nervous system effects is unknown. More complete information on the health effects of various congeners or congener classes would allow more informed scientific and risk assessment decisions.