TUESDAY, Aug. 20 (HealthDay News) -- By the time they reach the
fourth grade, children exposed to lead are nearly three times more
likely to have been suspended, a new study contends.
The findings from nearly 4,000 children in the Milwaukee school
district suggest that lead exposure may play more of a role in
school discipline problems than was realized, according to the
University of Wisconsin-Madison researchers.
"Students who are suspended from school are at greater risk of
dropping out, twice as likely to use tobacco, and more likely to
engage in violent behavior later in life," study first author
Michael Amato, a doctoral candidate in psychology and at the Nelson
Institute for Environmental Studies, said in a university news
Black students are three times more likely to be suspended than
white students nationally, according to background information in
the news release. The same difference was found in this study, but
differences in rates of lead exposure accounted for 23 percent of
the disparity, the researchers said.
Black children are more than twice as likely as white children
to have elevated lead levels, according to the U.S. Centers for
Disease Control and Prevention. Researchers attribute this to black
children being more likely to live in low-income neighborhoods and
rental housing where lead remains in the buildings and soil.
Many previous studies have identified disparities in school
discipline, but few have pinpointed the underlying factors, the
news release said.
"We knew that lead exposure decreases children's abilities to
control their attention and behavior, but we were still surprised
that exposed children were so much more likely to be suspended,"
study co-author Sheryl Magzamen, who is now an assistant professor
at the University of Oklahoma, said in the news release.
The researchers noted that animal experiments have shown that
lead causes decreased attention and decreased control over behavior
when an animal is startled or touched. If children exposed to lead
behave the same way, they're more likely to have disruptive
classroom behaviors that can result in suspension, according to the
Although the study found an association between childhood lead
exposure and increased risk of school suspension, it didn't prove
The study appears in the September issue of the journal
The U.S. Environmental Protection Agency has more about