Wanted: lead study's 1st recruits
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Don't miss Michael Martin's extensive research: A Strange Ignorance: The Role of Lead Poisoning in Failing Schools.
By Peggy O'Farrell
Kim Dietrich and his colleagues have collected stacks of data showing that lead exposure causes permanent brain damage.
Some of the data they've collected since 1979 shows a strong association between prenatal and early childhood lead exposure and arrests for criminal behavior during adulthood.
Dietrich and his colleagues gleaned that data from 300 babies and children they recruited between 1979 and 1984, and the countless blood samples, physical exams, questionnaires and interviews they collected from those kids - now all adults - and their parents.
The Cincinnati Lead Cohort Study, conducted by Dietrich and his colleagues at UC and Cincinnati Children's Hospital Medical Center, is the longest-running study on lead exposure and development in the United States.
Its findings have showed the havoc lead poisoning can wreak on young lives, from developmental impairment in preschoolers to links to anti-social behavior in teens and young adults, and resulted many "firsts" in research circles.
"We've looked at these subjects literally almost from conception through infancy, childhood, early and later adolescences, early adulthood into their early mid-20s, and now we're trying to bring them in again," Dietrich said. "It's difficult to maintain a cohort of this nature over a long period of time."
Now, Dietrich is asking those original participants to come back for one more - possibly the last - round of tests and questions. Participants will be compensated for time and travel.
The results should yield some interesting information about what effects lead exposure suffered prenatally and in early childhood might have into early and mid-adulthood.
Childhood lead exposure is linked to lower IQs, as well as problems with judgment, emotional control and attention.
Many of those links were first identified by Cincinnati researchers.
Among the findings from the study:
In 1993, the researchers published a study showing that preschoolers who'd been exposed to lead prenatally and in infancy had IQ deficits; higher blood lead levels were linked to lower IQ levels.
In 2008, the group published the first study showing an association between prenatal and blood lead levels and higher rates of criminal arrests, including for crimes involving violence, among 19- to 24-year-olds. Arrest rates were highest among those individuals with the highest blood lead levels measured in early childhood.
In 2009, the group published the first study showing that childhood lead exposure causes permanent brain damage with lifelong consequences. Dietrich and co-author Kim Cecil, a brain imaging specialist at Cincinnati Children's, used functional MRI technology to show the damage done to the brain.
From 1979 to 1984, Dietrich and his colleagues recruited pregnant women who lived in areas of the city known to have old housing stock with lots of lead paint - the main source of lead poisoning for American children.
Many of those neighborhoods - but not all - are among the poorest in the city, he said. Keeping track of the original participants hasn't been easy, Dietrich said.
"They tend to be pretty mobile, to have a lot of problems in terms of employment and education and other issues related to growing up in the inner city," he said.
So he's reaching out with billboards, flyers and posters, hoping to draw them back, to get a better idea of what impact lead exposure has had as they head toward middle age.
Many of the children Dietrich and his colleagues had very high blood lead levels, and the consequences have been evident over the years. More than half of the subjects were involved in some type of criminal activity.
"Almost invariably, these were the kids with the highest exposures," Dietrich said. "We have some of our subjects that we can't see again because they're in jail, in prison, serving long sentences for doing some pretty bad things."
As the subjects reached adulthood, some would call Dietrich - or their parents would call - to try to get information.
"They would come to me asking, 'Why can't I hold onto a job? Why can't I maintain a relationship?' Their moms would call, 'What's wrong with my son? Why can't he pay attention? Why is he always getting into trouble?' I can still hear these kids' voices when they were talking to me."
Litigation centered on the damaging effects of lead-based paint has abounded over the years, though lead-based paint was banned in the 1970s.
In October, a Baltimore woman was awarded $21 million after she sued the Housing Authority of Baltimore City for lead poisoning she suffered while living in an apartment as a child. The plaintiff's IQ was 89.
Many of the subjects enrolled in the Cincinnati study have done just fine in life, even those with elevated blood levels, Dietrich said.
But many haven't.
"Science talks about subtle effects. Lead's effects aren't subtle," he said.
"There are so many other factors involved in what's happened to these subjects. I'm well aware of that. We measure all of those other bad things, and good things. But lead always seems to be there in the picture. It's always there."
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