The more Milwaukee public school fourth graders were exposed to lead, the lower their grades, according to a University of Wisconsin study.
Comparing 3,757 students, those who tested higher for lead exposure scored worse on the state’s Knowledge and Concepts Exam, which measures math, reading and other skills, according to the study. Exposure among African American and Hispanic children were roughly double those of white children.
Differences in scores ranged from 5.2 in social studies to 9.8 in reading, said Mike Amato, a doctoral candidate in psychology and environmental studies. The differences made up a large chunk of the distinction between “basic” and “proficient” competence in a given subject.
The most common source of exposure is contaminated dust from paint in older homes, Amato reported. “Even low amounts of lead exposure during early development have direct, measurable, negative consequences for children’s school performance later in life.”
The study was originally published October 2012.