Reduced intellectual development in children with prenatal lead exposure.
Reduced intellectual development in children with prenatal lead exposure.
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减少了产前铅暴露儿童的智力发展。
DOI：
10.1289/ehp.8552
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发表时间：
2006-05
影响因子：
10.4
通讯作者：
中科院分区：
文献类型：
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作者：
出生后低水平铅暴露与儿童智力发育不良有关，尽管产前暴露的影响研究较少。我们假设产前铅暴露对儿童发育的影响比出生后暴露更强大且更持久。
我们使用具有随机截距和斜率的广义线性混合模型，分析从怀孕到10岁这一队列中铅对6至10岁儿童智商的影响模式。我们对剂量 - 反应非线性进行了统计学评估。
1987年至2002年期间，有175名儿童组成的队列在墨西哥城的国家围产期研究所就诊，其中150名儿童拥有所有纳入协变量的完整数据。
我们使用西班牙语版的韦氏儿童智力量表修订版来测量智商。血铅（BPb）由美国疾病控制与预防中心（CDC）血铅质量保证计划的一个参考实验室进行测量。
孕期血铅几何平均值为8.0微克/分升（范围为1 - 33微克/分升），1至5岁为9.8微克/分升（2.8 - 36.4微克/分升），6至10岁为6.2微克/分升（2.2 - 18.6微克/分升）。在控制其他血铅和协变量的情况下，只有随着孕晚期自然对数血铅的增加，6 - 10岁儿童的智商才显著下降（β = -3.90；95%置信区间为 -6.45至 -1.36）。血铅 - 智商的剂量 - 反应函数是对数线性的，而非线性 - 线性的。
妊娠约28周时的铅暴露是儿童后期智力发育的关键时期，具有持久且可能是永久性的影响。没有证据表明存在阈值；对智商影响最强的铅暴露发生在血铅的最初几微克范围内。
当前适用于儿童的美国疾病控制与预防中心行动限值应用于孕妇时，在所研究的血铅范围内，允许大多数与铅相关的儿童智商下降情况发生。
Low-level postnatal lead exposure is associated with poor intellectual development in children, although effects of prenatal exposure are less well studied. We hypothesized that prenatal lead exposure would have a more powerful and lasting impact on child development than postnatal exposure. We used generalized linear mixed models with random intercept and slope to analyze the pattern of lead effect of the cohort from pregnancy through 10 years of age on child IQ from 6 to 10 years. We statistically evaluated dose–response nonlinearity. A cohort of 175 children, 150 of whom had complete data for all included covariates, attended the National Institute of Perinatology in Mexico City from 1987 through 2002. We used the Wechsler Intelligence Scale for Children–Revised, Spanish version, to measure IQ. Blood lead (BPb) was measured by a reference laboratory of the Centers for Disease Control and Prevention (CDC) quality assurance program for BPb. Geometric mean BPb during pregnancy was 8.0 μg/dL (range, 1–33 μg/dL), from 1 through 5 years was 9.8 μg/dL (2.8–36.4 μg/dL), and from 6 through 10 years was 6.2 μg/dL (2.2–18.6 μg/dL). IQ at 6–10 years decreased significantly only with increasing natural-log third-trimester BPb (β = −3.90; 95% confidence interval, −6.45 to −1.36), controlling for other BPb and covariates. The dose–response BPb–IQ function was log-linear, not linear–linear. Lead exposure around 28 weeks gestation is a critical period for later child intellectual development, with lasting and possibly permanent effects. There was no evidence of a threshold; the strongest lead effects on IQ occurred within the first few micrograms of BPb. Current CDC action limits for children applied to pregnant women permit most lead-associated child IQ decreases measured over the studied BPb range.