More than half of the U.S. population alive today was exposed to leaded gas exhaust in childhood — collectively stealing more than 824 million IQ points, say the authors of a recent study published in Proceedings of the National Academy of Sciences. More than 170 million Americans born between 1951 and 1980 lost an average of nearly three IQ points each as a result of this exposure, but longer-term health impacts are not yet known.
“Lead exposures are ongoing and they’re larger than we thought,” says Aaron Reuben, a PhD candidate in clinical psychology at Duke University. “First off, lead is toxic to almost every organ in the system. There are implications for health and disease across every field you can think of.” Reuben and his co-authors at Florida State University estimated the impact on IQ, he says, because it’s a clear measure of brain health.
