Possibles sources of lead poisoning
In what may be the strongest link yet between lead exposure and crime rates, researchers at the University of Cincinnati on Tuesday released new evidence, spanning more than 20 years, that draws a direct relationship between the amount of lead in a child’s blood and the likelihood he or she will commit crimes as an adult.
Research has shown before that lead has harmful effects on judgment, cognitive function and the ability to regulate behavior. But until now the best research focused on juveniles, not adults.
Now, researchers have collected data from as early as 1979 when pregnant women and their healthy babies had their blood drawn regularly at four Cincinnati medical clinics. By the time the children were 7, researchers had a complete portrait of lead levels.
Nearly two decades later, the researchers tracked down 250 of the subjects, ages 19-24. Controlling for a host of factors, including parental IQ, education, income and drug use, the team found that the more lead in a child’s blood from birth through age 7, the more likely he or she was to be arrested as an adult. The tie between high lead levels and violent crime was particularly strong.
“We need to be thinking about lead as a drug and a fairly strong one,” says Kim Dietrich, a professor of environmental health at the University of Cincinnati College of Medicine and the principal investigator for the study in the journal Public Library of Science Medicine. “These kids have been exposed to this drug, chronically, since before birth.”
For nearly 50 years, researchers have known about the relationship between children’s impulsivity and high levels of lead in their bodies. As recently as 2007, economist Rick Nevin tied violent crime rates to historic use of leaded gasoline.
Children in poor neighborhoods are often exposed to high levels of lead from old lead paint in dilapidated homes.
Fordham University School of Law criminologist Deborah Denno, who has studied the effects of lead, calls the findings’ ties to adult criminal behavior “very important.” Denno studied National Institutes of Health statistics of nearly 1,000 children in Philadelphia and found that a high blood lead level at 7 years old was among the strongest predictors that a child would have both learning difficulties and disciplinary problems in school. High blood lead also strongly predicted whether a child would have a juvenile or adult criminal record.
Denno says Tuesday’s data are newer than hers by 20 years. “It’s still a huge problem,” she says, “and it’s still a huge problem among African-American communities and poorer neighborhoods.”
Via USA Today