Exposure to lead in childhood can significantly reduce children's scores in end-of-year reading tests. Researchers from Duke University and North Carolina Central University looked into the links between levels of lead in children's bloodstreams, poverty and parental education, and reading scores for children at the end of Year 4. They found that parental education accounted for 58-65% of the decline in scores for minority and low-income children, poverty status accounted for 25-28% and blood lead levels for 7-16%. The effect of lead was more noticeable for children who already had low test scores and the higher the children's lead levels the greater the impact on their scores. But the exposure to lead also had an impact on children who scored highly on the tests; enough to disqualify them from programmes aimed at gifted children.
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