Do Low Levels of Blood Lead Reduce Children’s Future Test Scores?
This study examines the link between preschool blood lead levels with third grade test scores of Rhode Island children born between 1997 and 2005. The data shows that reductions of lead from even historically low levels have significant positive effects on children’s reading test scores in third grade.
The estimates suggest that a one unit decrease in average blood lead levels reduces the probability of being substantially below proficient in reading by 3.1 percentage points. Poor and minority children are more likely to be exposed to lead, suggesting that lead poisoning may be one of the causes of continuing gaps in test scores between disadvantaged and other children.