Oct. 18, 2003, 12:16AM
Antidepressant traces in creek raise concernsFort Worth
Baylor University have found traces of a pharmaceutical
antidepressant in the livers, muscles and brains of bluegills in a
Denton County creek, raising concerns about the welfare of the
popular sports fish and people who eat them.
The Baylor study raises more questions than answers. Among
· Can these pharmaceuticals pollute drinking water
· What are the health effects of eating fish contaminated
· If fluoxetine is in the bluegills in Pecan Creek, might
it also be in the biological tissues of other species in other
The chemical is fluoxetine -- the primary component in Prozac. It
likely came from a city of Denton wastewater treatment plant, which
discharges into Pecan Creek and flows into Lake Lewisville in North
Texas. Traces of the drug that are not absorbed into the body can
flow down the toilet and through wastewater treatment plants, which
are not designed to filter out pharmaceuticals.
Fluoxetine and other antidepressants affect fish in roughly the
same ways they affect people, said Bryan Brooks, a Baylor
toxicologist who led the study. It relaxes them.
"Maybe it makes you a happy fish and you're kind of hanging out,"
Brooks said. "But how does that influence your ability to capture
prey? Do you instantly become candy for large-mouth bass because
you're accumulating large amounts of Prozac in your system? These
are areas where more research is needed."
Brooks will present the results of his study next month in
Austin, at the annual meeting of the Society of Environmental
Toxicology and Chemistry.
It's believed to be among the first studies to show that
antidepressants in the water can accumulate in biological tissue,
raising the possibility of long-term health and behavioral problems
in fish, said Marsha Black, an aquatic toxicologist at the
University of Georgia.
"That's really a significant finding," said Black, who's using a
federal grant to study the health effects of fluoxetine and other
antidepressants in fish. "This opens up the door and says these
things are important."
Brooks' latest research comes on the heels of recent studies he
helped conduct while a graduate student at the University of North
That research found that some male fish in Denton County are
developing female characteristics because estrogen from prescription
drugs is winding up in the water. The estrogen -- from birth control
pills, hormone replacement therapy and other sources -- could reduce
the fish population by rendering some males unable to breed.
The issue has garnered national attention in the past few years.
A U.S. Geological Survey study last year found that 80 percent of
the 139 streams it sampled in 30 states, including Texas, contained
small amounts of pharmaceutical drugs, hormones, steroids and
personal care products such as perfumes.
"It's very common," said Herbert Buxton, coordinator of the
Geological Survey's Toxic Substances Hydrology Program. "What this
tells us is that these wastewater pathways are worthy of a lot more
Brooks said he has already expanded the research to include
catfish and black crappie.
He said Pecan Creek was picked as the study site because it gets
as much as 13 million gallons a day of treated wastewater from
Denton's Pecan Creek Water Reclamation Plant.
During the dry summer months, the wastewater from the plant
comprises nearly all the creek's water flow.