Level of lead in youths' blood can lower academic scores by up to 50%
Children can suffer cognitive and behavioral damage from lead exposure at half the blood levels currently considered safe, according to a study conducted by researchers from the University of Bristol Center for Child and Adolescent Health and published in the journal Archives of Disease in Childhood.
"Lead in the body is one of many factors that [has an] impact on education, but this is a reminder that environmental factors are important and pediatricians must test more children with behavioral problems for lead," said lead researcher Alan Emond.
Researchers tested the blood of 582 children, all of whom were 30 months of age, then followed them until they were seven or eight years old. After adjusting for other factors, they found that children who had blood lead levels between 5 and 10 micrograms per deciliter scored an average of 49 percent lower on reading tests and 51 percent lower on writing tests than children with levels below 5 micrograms.
The maximum level considered safe by the British and U.S. governments is 10 micrograms per deciliter. Lead is a neurotoxin that is especially damaging to fetuses and young children, although it can harm the brains and nervous systems of adults, as well.
Children with blood lead levels higher than 5 micrograms per deciliter were also significantly more likely to exhibit antisocial behavior and hyperactivity than children with lower lead levels. Children with levels above 10 micrograms per deciliter scored even worse on hyperactivity, antisocial behavior, and educational performance tests than children in the 5 to 10 microgram per deciliter group.
[...]Twenty-seven percent of the children tested had lead levels higher than 5 micrograms per deciliter.