| Tuesday,
September 5, 2006 |
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Study shows solvents
damaged workers' brains
Researchers studying railroad workers have documented that
cleaning solvents used in their jobs caused brain damage, shrinking
the vital bridge that helps one side of the brain communicate with
the other.
The results of the study by researchers from West Virginia
University, the University of Pittsburgh and Johns Hopkins
University, which was funded by the federal government, bolster
evidence that powerful degreasers can damage the brain.
They also lend further
credence to claims by hundreds of railroad workers, many from
Kentucky and some from Indiana, diagnosed with brain damage after
cleaning locomotives with solvents from the 1950s through the early
1990s.
"We were able to identify a change to the structure of the
brain," said lead author Marc Haut, a professor in the departments
of behavioral medicine and psychiatry, neurology and radiology at
the West Virginia University School of Medicine in Morgantown.
The researchers sought funding for the study after numerous
railroad workers with the same symptoms began showing up in the
researchers' clinics, Haut said.
"Those railroad workers with more exposure or severe exposure had
a greater loss of (brain) volume," Haut said.
He said they found a correlation between brain loss and workers'
performance on tests that evaluate such mental performance as
processing speed, attention and concentration.
The new report is the first connected with the nation's first
large, independently funded study that seeks to explain how railroad
workers may have been affected by solvents like
1,1,1-trichloroethane, trichloroethylene and perchlorethylene.
Workers who participated in the study came from railroad shops in
Cumberland, Md., and Huntington, W.Va.
"It is no surprise to me," Deanna Bowerman said of the study's
findings.
Her late husband, Dale, was a CSX railroad machinist in
Louisville and Corbin, Ky., and was diagnosed with toxic
encephalopathy -- characterized by chronic depression, loss of
short-term memory and hair-trigger temper.
Although Dale Bowerman was not part of the West Virginia study,
Deanna Bowerman, of Harrison County, Ind., said doctors told the
couple years ago that her husband had suffered permanent brain
damage. Effect of
solvents
In a 10-month investigation in 2000 and 2001, The Courier-Journal
learned that Bowerman and more than 600 other U.S. railroad
employees had been diagnosed with toxic encephalopathy after
spending years in workplaces where solvents were widely used with
little or no protection.
The newspaper found that the debate within the medical community
about whether exposure to solvents in the workplace caused brain
damage had diminished in the 1990s.
But studies of railroad workers were less common, and some that
were funded by CSX Transportation had found no link between solvent
exposure and the illness. The newspaper found that CSX, the railroad
company with the largest number of claims, had paid out nearly $35
million to more than 460 current or former workers diagnosed with
the illness.
Railroads began phasing the chemicals out of their shops in the
early 1990s.
CSX has both won and lost jury verdicts in chemical exposure
cases that have gone to trial. It has argued that its workers'
problems could be explained by other factors, such as drinking
alcohol, side effects from prescribed medication, or illnesses such
as depression or diabetes.
Gary Sease, a spokesman for CSX, said the company continues to
believe there is no credible and conclusive scientific basis to
support claims that solvent exposure harmed company workers.
Joe Satterley, a Louisville attorney who represents railroad
workers, said he's aware of at least 100 pending lawsuits in
Kentucky and elsewhere that were filed in the last few years.
The study, he said, "substantiates everything we've been saying
all along." Brain images
compared
The findings of eight researchers were published in June in the
Journal of Occupational and Environmental Medicine. They are based
on comparing images of the brains of 31 railroad workers who were
exposed to solvents over a period of at least 10 years to 31 people
who were not.
Any workers involved in pending litigation with the railroad were
excluded, as were those with current substance abuse, a history of
serious medical illness, or a diagnosis of mental illness before
solvent exposure, Haut said. The researchers also factored out
potential effects from high blood pressure and diabetes, which can
cause the brain to shrink.
With funding from the National Institute for Occupational Safety
and Health, the researchers found that the size of the corpus
callosum -- a bridge between the left and right hemispheres of the
brain that allows communication between the sides -- was
significantly smaller in the railroad workers.
And the part most affected, they found, was the genu, a section
of the corpus callosum that connects the frontal lobes, which are
associated with decision making, problem solving and emotions.
The researchers also concluded that psychiatric conditions, such
as depression, could not have caused the physical changes in
workers' brains.
As another part of the study, the researchers are analyzing
images that compare brain function while participants take certain
mental tests.
Haut said the research will help professionals better understand
the medical problems of people in other industries exposed to
solvents.
Dr. Alan Ducatman, a co-author of the study and chair of the
department of community medicine at West Virginia University's
medical school, has diagnosed more than 100 railroad workers with
the illness. He said there are also implications for anyone who is a
heavy drinker of alcohol, which is also considered a solvent.
"For all of the intoxicants, the problem ... is knowing the
threshold before safety is breached," he said.
Reporter James Bruggers can be reached at (502) 582-4645.
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