Chemicals take toll on dolphin - PRBEs linked to diseases in lagoon bottlenose - eg, herpe

Chemicals take toll on dolphin

Scientists find substance linked to diseases in lagoon bottlenose
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BY JIM WAYMER
FLORIDA TODAY
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/[foto] New maladies. A number of new diseases have been attacking
dolphin, including herpes. Researcher Greg Bossart says flame retardants
called polybrominated diphenyl ethers, or PBDEs, found in bottlenose
dolphin have the "potential of opening up these animals to a Pandora's
box of diseases." Harbor Branch Oceanographic Institution

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Scientists have discovered chemicals used to fireproof plastics and
products in the blood and blubber of bottlenose dolphin in the Indian
River Lagoon.

They don't yet know for certain how the chemicals got there, but they
suspect they could be playing a role in the new diseases, such as
herpes, that are attacking the marine mammals.

"The data suggests at this point that these flame retardants suppress a
part of the immune system that makes antibodies," said Greg Bossart, one
of the researchers who made the discovery. "There's a potential of
opening up these animals to a Pandora's box of diseases."

Bossart and his colleagues found flame retardants called polybrominated
diphenyl ethers or PBDEs in tests* *of* *dolphin in the lagoon and in
Charleston Harbor, S.C. They measured mean levels of total PBDEs in
lagoon dolphin at about 1,500 parts per billion in fat tissue, more than
three times the highest levels found in humans, 500 parts per billion.

Bossart said the research hasn't determined what level of PBDEs has
significant effect on dolphin or human health.

"What we do know is that we found these chemicals*," *he said. "My
concern is that we're documenting these emerging diseases in bottlenose
dolphins."

For example, when the dolphin health study began in 2003, his research
team found no oral or genital tumors on lagoon bottlenose dolphin. Last
year, 47 percent had tumors.

"There's something that's going on that's allowing this disease to
manifest itself," Bossart said.

The team plans to publish its* *results in coming months.

*Testing*

In the third of five years, the study compares the health of lagoon
bottlenose to bottlenose in Charleston Harbor. Most of the $1.25 million
for study--scientists have* *spent about $800,000 so far -- comes from
sales of* *Florida's* *dolphin license plates.

Bossart and his colleagues drew blood and plasma samples from 113
bottlenose dolphin -- ages 3.5 to 28 years old -- in the lagoon and
harbor in summers 2003 and 2004.

He said the South Carolina dolphin tested at higher levels of PBDEs than
lagoon dolphin likely* *because the area has more industry.

Bossart said the* *PBDEs may be linked to the* *increased rates of
tumors caused by viruses, stomach ulcers from bacterial infections and
other conditions afflicting dolphin.

But the finding also raises concern about whether humans may be at risk.

Studies show PBDEs don't break down easily and may be linked to cancer
and birth defects, including ones that affect brain and thyroid development.

"It's not readily metabolized by the body," said Erin Hughes, marine
biologist and aquatic toxicologist at University of Florida's Center for
Environmental and Human Toxicology. "They will biomagnify in larger
organisms. They stick to fat and blubber."

*Human impact*

PBDEs are widely used flame retardants rising rapidly in human tissues.
Studies have found them in blood, breast milk and fat. They're blended
into plastics and foams used for computer casings, carpet pads and foam
cushions on chairs and couches.

A California ban on two forms of PBDEs takes effect later this year.

People can take in the chemical by contact but mostly ingest it from
foods. Salmon and catfish typically have the highest levels among fish,
tilapia the lowest, according to studies by the U.S. Environmental
Protection Agency. Pork, sausage and bacon can also have high levels.

PBDEs settle in sediments, then make their way up the food chain to
marine mammals, fish and bird eggs. They run off in stormwater and seep
up from contaminated groundwater and sewage.

*"*Wastewater's probably the most likely source of this," said John
Windsor, a professor at Florida Tech's department of marine and
environmental sciences. "It's hard to say exactly that these things are
causing the effect, because there might be something else in the water
we're not looking for causing the effect."

*Health crisis*

Windsor said PBDEs have not yet been found in the lagoon.

"It's too low in concentration, so it's hard to measure," he said. "We
can analyze things at very low concentrations, we just don't know what
the effects are."

The PBDE discovery adds to a growing* *list of chemicals and
environmental stresses Bossart said might be clues to emerging dolphin
epidemics.

"Our data certainly suggests that these animals are on the edge of a
health crisis," he said.

*/*Contact Waymer at 242-3663* *or jwaymer flatoday.net