November 15, 2010
The Texas Department of State Health Services has issued an advisory against
consuming blue catfish, channel catfish and smallmouth buffalo from Lake Worth
in Tarrant County.
The advisory was issued after laboratory testing showed elevated levels of
polychlorinated biphenyls, or PCBs, along with the insecticides aldrin and
dieldrin in fish samples collected from the lake. This advisory replaces a 2000
advisory that warned against consuming all species of fish from Lake Worth due
to elevated levels of PCBs.
DSHS tested tissue samples from seven species of fish as part of a
re-evaluation of the lake. Analysis found levels of PCBs in blue catfish and
smallmouth buffalo that exceed DSHS standards, indicating that consumption of
those fish pose a risk to human health. The combination of PCBs, aldrin and
dieldrin found in channel catfish also pose a risk to human health.
DSHS did not find elevated levels of contaminants in samples of common carp,
freshwater drum, largemouth bass or white crappie collected from Lake Worth.
PCBs are industrial chemicals once used as coolants and lubricants in
electrical transformers and capacitors. The U.S. Environmental Protection Agency
banned PCBs in 1979, but items containing PCBs did not have to be replaced. PCBs
degrade slowly in the environment, and long-term consumption of PCBs may cause
cancer and reproductive, immune system, developmental and liver problems.
Aldrin and dieldrin are insecticides that may cause cancer, birth defects and
kidney damage in humans. Their use in the United States was restricted by the
EPA in 1974 and banned in 1987, but they remain in the environment for
Elevated levels of PCBs and insecticides in fish do not pose a health risk
for people participating in water recreation activities in Lake Worth.
(News Media Contact: Chris Van Deusen, DSHS Assistant
Press Officer, 512-458-7753)
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