Overall, the researchers from Florida State University and Duke University found, childhood lead exposure cost America an estimated 824 million points, or 2.6 points per person on average. Certain cohorts were more affected than others. For people born in the 1960s and the 1970s, when leaded gas consumption was skyrocketing, the IQ loss was estimated to be up to 6 points and for some, more than 7 points. Exposure to it came primarily from inhaling auto exhaust.
“Lead is a neurotoxin, and no amount of it is safe.