BACKGROUND Studies with children exposed to methylmercury (MeHg) through fish consumption in the Brazilian Amazon region report that the high levels of hair Hg are associated with significant decreases in intelligence, memory, attention, and visuospatial processing. OBJECTIVE To investigate the relationship between mercury exposure and neuropsychological functions in riverside communities of the Brazilian Amazon. METHOD 263 participants aged 6 to 14 years old were assessed, from resettlement regions, near the Madeira river, Rondônia, Brazil. To assess the neuropsychological functions we used the following instruments: intelligence (WASI), working memory (Corsi Block-Tapping Task and Digit Span), verbal fluency (Word Generation - NEPSY II), inhibitory control (Inhibition Errors - NEPSY II), shifting (Trail Making Test) and manual motor dexterity (Grooved PegBoard Test). Socioeconomic status was obtained through household surveys. Total Hg levels were quantified hair samples (Total HgH) collected from the occipital region of the scalp and analyzed by Cold Vapor Atomic Absorption Spectrometry. RESULTS The group in the upper quartile of Total HgH levels presented lower scores on the tasks that assessed estimated IQ, visuospatial working memory, semantic knowledge and phonological verbal fluency, when compared to the group in the lower quartile level. A regression analysis controlled for age, sex, and maternal education showed that for each increase of 10 μg/g of Total HgH, there was a decrease around half standard deviation in Verbal IQ, estimated IQ scores, semantic knowledge, phonological verbal fluency and for verbal and visuospatial working memory. CONCLUSIONS High concentrations of Total Hg in hair were associated with a lower performance in neuropsychological functions tests. The results show that environmental exposure to Hg is associated to children and adolescents' lower neuropsychological performance in the riverine and resettled areas of the Brazilian Amazon region.

中文翻译：

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汞暴露对巴西亚马逊地区儿童和青少年的神经心理影响。

背景技术在巴西亚马逊地区，通过食用鱼类接触甲基汞（MeHg）的儿童的研究报告说，高水平的头发Hg与智力，记忆力，注意力和视觉空间加工能力的显着降低有关。目的探讨巴西亚马逊河沿岸社区汞暴露与神经心理功能之间的关系。方法对来自巴西朗多尼亚马德拉河附近安置区的263名6至14岁的参与者进行了评估。为了评估神经心理功能，我们使用了以下工具：智力（WASI），工作记忆（Corsi敲击任务和数字跨度），语言流利性（单词生成-NEPSY II），抑制性控制（抑制错误-NEPSY II），换档（制车测试）和手动运动灵活性（带凹槽的PegBoard测试）。社会经济地位是通过家庭调查获得的。总Hg水平是从头皮枕叶区收集的定量头发样本（总HgH），并通过冷蒸气原子吸收光谱法进行分析。结果与四分位数较低的组相比，总HgH水平较高的四分之一组在评估估计智商，视觉空间工作记忆，语义知识和语音语言流畅性的任务上得分较低。根据年龄，性别和孕产妇教育进行的回归分析显示，每增加10μg/ g总HgH，口头智商，估计智商得分，语义知识，语音口语流利度以及用于语音和视觉空间的工作记忆。结论头发中总Hg的高浓度与神经心理学功能测试的较低表现有关。结果表明，在巴西亚马逊河地区的河流和移民地区，环境中汞的暴露与儿童和青少年较低的神经心理表现有关。