CURWOOD: Just ahead, science is at work trying to bring mini suns to the earth. First this Environmental Health Note from Diane Toomey.

TOOMEY: In the past few years, there has been increasing concern that childhood exposure to lead may play a role in juvenile delinquency. Now, the results of a recently published study add to that concern.

University of Pittsburgh researchers measured the bone lead levels in almost 200 juvenile delinquents convicted of crimes such as gun possession, drug dealing, assault and robbery. They administered the same test to a group of non-delinquent high schoolers from the same area and found that the juvenile delinquents had a lead concentration more than seven times greater than the non-delinquent group.

Herbert Needleman, a pioneer in lead research who headed this study, says it’s not clear how lead exposure might cause delinquent behavior. The neurotoxin may affect the brain’s pre-frontal lobes where impulsiveness is controlled. Or the effect could be due to the poor school performance and learning disabilities found in lead-exposed children. It’s been shown that poor school performance is a factor in delinquency.

Needleman notes that lead exposure alone doesn’t cause juvenile delinquency. But when he controlled for other factors, including race, absence of two parental figures in the home and neighborhood crime rate, Needleman says lead level was still the second strongest risk factor for juvenile delinquency, exceeded only by race.

That’s this week’s Health Note. I’m Diane Toomey.

CURWOOD: And you’re listening to Living on Earth.