Abstract：
OBJECTIVE: Strong experimental evidence exists that several endocrine disrupting chemicals (EDCs) have neurobehavioral toxicity. However, evidence of associations between prenatal exposure and child\'s cognitive development is inconsistent. Moreover, toxicants are generally analyzed one by one without considering aggregate effects. We examined here the impact of a prenatal exposure to a mixture of persistent organic pollutants (POPs) on intellectual abilities in preschool children, and compared their effects to those described in the literature.
METHODS: Sixty-two children were included in a longitudinal cohort. Four organochlorine pesticides, four polychlorinated biphenyls (PCBs) and seven perfluorinated compounds (PFCs) were measured in cord blood. Intellectual abilities were assessed at 6 years of age using the Wechsler Preschool and Primary Scale of Intelligence 4th ed. (WPPSI-IV). We examined the associations between a mixture of POPs and cognitive performances using principal components approach (PCA) and weighted quantile sum (WQS) regression taking sex difference into account.
RESULTS: No negative correlation was found when analyses were performed on boys and girls together. In sex-stratified analyses, lower scores in full scale intelligence quotient (FSIQ) and fluid reasoning index (FRI) were observed in boys most exposed to a mixture of POPs. Increase of the WQS index was also associated with lower verbal comprehension index (VCI) scores in girls only. No other negative correlation was found using both WQS and PCA models.
CONCLUSIONS: Our study suggests deleterious associations between antenatal exposure to a mixture of POPs and sex-specific cognitive level, clarifying some trends described in the literature.
METHODS: Sixty-two children were included in a longitudinal cohort. Four organochlorine pesticides, four polychlorinated biphenyls (PCBs) and seven perfluorinated compounds (PFCs) were measured in cord blood. Intellectual abilities were assessed at 6 years of age using the Wechsler Preschool and Primary Scale of Intelligence 4th ed. (WPPSI-IV). We examined the associations between a mixture of POPs and cognitive performances using principal components approach (PCA) and weighted quantile sum (WQS) regression taking sex difference into account.
RESULTS: No negative correlation was found when analyses were performed on boys and girls together. In sex-stratified analyses, lower scores in full scale intelligence quotient (FSIQ) and fluid reasoning index (FRI) were observed in boys most exposed to a mixture of POPs. Increase of the WQS index was also associated with lower verbal comprehension index (VCI) scores in girls only. No other negative correlation was found using both WQS and PCA models.
CONCLUSIONS: Our study suggests deleterious associations between antenatal exposure to a mixture of POPs and sex-specific cognitive level, clarifying some trends described in the literature.
摘要：
目的：有强有力的实验证据表明，几种内分泌干扰化学物质（EDCs）具有神经行为毒性。然而,产前暴露与儿童认知发育之间关联的证据不一致。此外，毒物通常是在不考虑聚集效应的情况下逐一分析的。我们在这里研究了产前暴露于持久性有机污染物（POPs）混合物对学龄前儿童智力的影响，并将它们的效果与文献中描述的效果进行了比较。
方法：将62名儿童纳入纵向队列。四种有机氯农药,在脐带血中测量了四种多氯联苯（PCBs）和七种全氟化合物（PFCs）。使用韦克斯勒学龄前和初级智力量表第4版评估6岁时的智力。(WPPSI-IV)。我们使用考虑性别差异的主成分方法（PCA）和加权分位数和（WQS）回归研究了POP混合物与认知表现之间的关联。
结果：当一起对男孩和女孩进行分析时，没有发现负相关。在性别分层分析中，在暴露于持久性有机污染物混合物的男孩中，观察到全面智商（FSIQ）和流体推理指数（FRI）得分较低。仅在女孩中，WQS指数的增加也与较低的言语理解指数（VCI）得分有关。使用WQS和PCA模型均未发现其他负相关。
结论：我们的研究表明，产前暴露于持久性有机污染物混合物与性别特异性认知水平之间存在有害关联，澄清文献中描述的一些趋势。
方法：将62名儿童纳入纵向队列。四种有机氯农药,在脐带血中测量了四种多氯联苯（PCBs）和七种全氟化合物（PFCs）。使用韦克斯勒学龄前和初级智力量表第4版评估6岁时的智力。(WPPSI-IV)。我们使用考虑性别差异的主成分方法（PCA）和加权分位数和（WQS）回归研究了POP混合物与认知表现之间的关联。
结果：当一起对男孩和女孩进行分析时，没有发现负相关。在性别分层分析中，在暴露于持久性有机污染物混合物的男孩中，观察到全面智商（FSIQ）和流体推理指数（FRI）得分较低。仅在女孩中，WQS指数的增加也与较低的言语理解指数（VCI）得分有关。使用WQS和PCA模型均未发现其他负相关。
结论：我们的研究表明，产前暴露于持久性有机污染物混合物与性别特异性认知水平之间存在有害关联，澄清文献中描述的一些趋势。
