A new study that analyzed medical and discipline data from Milwaukee Public Schools found young children who are exposed to lead are nearly three times more likely to be suspended from school by the fourth grade.
Lead — commonly found in paint in older homes and rental properties — may be more responsible for school discipline problems than previously realized, according to the study’s author, Michael Amato, a doctoral candidate in the psychology department and the Nelson Institute for Environmental Studies at the University of Wisconsin-Madison.
Lead has been cited as a contributor to the academic achievement gap between black and white children because the powerful neurotoxin is more likely to be found in low-income housing. High levels of lead in the bloodstream may make children more likely to behave impulsively and may shorten their attention spans, according to previous research.
While previous studies have documented racial disparities in school discipline, few have specified the underlying factors, according to Amato, who believes his is the first study of the link between suspensions and lead exposure.
Nationally, African-American students are three times more likely to be suspended than white students. The same discipline gap was found in the UW study, but 23% of the disparity was explained by differences in rates of lead exposure, even after controlling for income, race/ethnicity and gender.
Researchers led by Amato analyzed medical and school discipline records of about 3,000 MPS students.
Among the students whose blood tested positive for lead exposure, 31% had been suspended at least once by fourth grade. Among those not exposed to lead, 11% had been suspended by then, Amato said.
The study, jointly funded by the Robert Wood Johnson Foundation and the Wisconsin Partnership Program Education and Research Committee, will be published in the September issue of Environmental Research.
Milwaukee public health officials and physicians advise parents to get their children tested for lead exposure three times before the children turn 3. The results go into their medical records.
Younger children — once they’re mobile and before they turn 3 — are at highest risk for elevated lead levels because they may crawl through lead dust particles released from a window that’s opened and closed, and then put their fingers in their mouths, said Geoffrey Swain, chief medical officer and medical director for the Milwaukee Health Department.
Through aggressive efforts to promote lead testing for children, and federally funded lead abatement programs run by the Milwaukee Health Department, the prevalence of lead poisoning among children under age 6 has declined from 34% in 1997 to 3.3% today, said Paul Biedrzycki, director of disease control and environmental health for the Milwaukee Health Department.
“This study adds to the body of evidence,” he said. “You can no longer discount low-level lead as not contributing to lower achievement and delinquency, and even criminal behavior down the road.”
“It’s simple, straight-forward and compelling,” Swain said.
Now, in addition to affecting children’s ability to learn and control impulses, lead exposure also may someday land them in jail, Swain said.
Unfortunately, Swain and Biedrzycki said, federal funding for lead abatement programs in cities such as Milwaukee has been drastically cut in the last 18 months, reducing by half the number of housing units that will receive lead abatement this year in Milwaukee.
“This issue tends to be painted in the public health corner, but it affects jobs, education and public safety,” Biedrzycki said.
Lead was banned from paint in 1978. In Milwaukee, roughly 220,000 rental units and single-family houses were built before 1978 and possibly have lead paint, Biedrzycki said.
Of those residential units, the Health Department figures 130,000 are at risk for lead because they were built before 1950. Of the 130,000 units, the city’s lead abatement teams so far have addressed 16,482, said Biedrzycki, who directs the city’s lead reduction program.
It costs the city about $5,000 to do lead abatement in each residential unit.