Background

Few studies have evaluated the association between low-level arsenic (As) exposure and cognitive performance among children.

Objectives

In this cross-sectional study, we assessed the association between low-level As exposure and cognitive performance among 5–8 year-old children in Montevideo, and tested effect modification by As methylation capacity and children's dietary folate intake.

Methods

We measured total urinary As (UAs) concentrations and the proportion of monomethylarsonic acid (MMA) in the urine of 328 children. Seven subtests of the standardized Woodcock-Muñoz cognitive battery were used to assess cognitive performance, from which, the general intellectual abilities (GIA) score was derived. Total folate intake was estimated from two 24-h dietary recalls. Linear regression analyses were performed. Effect modification was assessed by stratifying at the median %MMA value and tertiles of total folate intake calculated as micrograms (µg) of dietary folate equivalents (dfe).

Results

The median UAs was 11.9 µg/l (range = 1.4–93.9), mean folate intake was 337.4 (SD = 123.3) µg dfe, and median %MMA was 9.42 (range = 2.6–24.8). There was no association between UAs and cognitive abilities, and no consistent effect modification by %MMA. UAs was associated inversely with concept formation, and positively with cognitive efficiency and numbers reversed subtest in the lowest folate intake tertile; UAs was also positively associated with sound integration in the second tertile and concept formation in the highest tertile of folate intake. There was no consistent pattern of effect modification by %MMA or folate intake.

Conclusion

There was no association between low-level As exposure and general cognitive abilities.

中文翻译：

---

一项低水平砷暴露的乌拉圭学龄儿童的一般认知能力的横断面研究，甲基化能力和饮食中叶酸对潜在影响的调节

背景

很少有研究评估儿童低水平砷暴露与认知能力之间的关系。

目标

在这项横断面研究中，我们评估了蒙得维的亚5-8岁儿童中低水平砷暴露与认知能力之间的关联，并测试了砷甲基化能力和儿童膳食叶酸摄入量对效果的改善。

方法

我们测量了328名儿童尿液中总尿As（UAs）浓度和一甲基砷酸（MMA）的比例。标准化伍德考克-穆尼兹认知电池的七个子测试用于评估认知表现，从中得出一般智力（GIA）分数。从两次24小时饮食召回中可以估算出叶酸的总摄入量。进行线性回归分析。通过将％MMA值的中位数和以总叶酸当量（dfe）的微克（µg）计算的总叶酸摄入量的三分位数分层来评估效果改善。

结果

UAs中位数为11.9 µg / l（范围= 1.4–93.9），平均叶酸摄入量为337.4（SD = 123.3）µg dfe，中位％MMA为9.42（范围= 2.6–24.8）。UA和认知能力之间没有关联，％MMA也没有一致的效果修饰。在最低的叶酸摄入量中，UAs与概念的形成呈负相关，与认知效率和数字反演呈正相关。UAs与第二个三分位数中的声音整合和叶酸摄入量最高的三分位数中的概念形成也呈正相关。没有通过％MMA或叶酸摄入来改变效果的一致模式。

结论

低水平砷暴露与一般认知能力之间没有关联。