Low-level environmental lead exposure and children's intellectual function: an international pooled analysis

Abstract

This study examined the association between blood lead levels and intelligence in 1,333 children from seven international cohorts. The results show an inverse relationship between blood lead concentration and IQ score, even for children with maximal blood lead levels below 10 μg/dL. A log-linear model revealed a significant 6.9 IQ point decrement associated with an increase in blood lead levels from 2.4 to 30 μg/dL. Importantly, children with a maximal blood lead level below 7.5 μg/dL experienced greater intellectual deficits per unit increase in blood lead compared to those with higher maximal levels. This study highlights the detrimental effects of even low-level lead exposure on cognitive development, emphasizing the need for comprehensive strategies to mitigate lead exposure in children.