[Pharmwaste] Mysterious seal deaths linked to food chain contaminants

[DeBiasi,Deborah]

http://www.capecodonline.com/apps/pbcs.dll/article?AID=/20071015/NEWS/71
0150327

Mysterious seal deaths linked to food chain contaminants

By Doug Fraser
STAFF WRITER

October 15, 2007 6:00 AM

It's a great irony of the modern world that attempts to make us safer
sometimes make us less so. Fire causes billions of dollars in damage
every year and kills thousands. Plastic items like small electronic gear
and building materials are petroleum-based and would be very flammable
if not for chemicals added during the manufacturing process known as
brominated flame retardants, or BFRs.

But researchers are now finding that these chemicals have entered our
food chain and might have a role in the recent deaths of hundreds of
seals - and could ultimately be harming people as well.

"The highest levels (of BFRs) in the world are in the U.S., 10 to 40
times higher than Asia and Europe," said Susan Shaw, an environmental
toxicologist attempting to solve the mysterious deaths of as many as
1,000 otherwise healthy adult harbor seals and gray seals along the New
England coastline over the past three years.

The National Marine Fisheries Service declared two "unusual mortality
events" for seals, one in 2004 and one in 2006. The declaration releases
funding allowing a greater level of tissue sampling. Since 2006,
researchers have sampled nearly 500 animals, most of which were dead.
The die-off appears to be tailing off, with only 35 animals reported in
2007, but investigators have yet to find a clear cause, said NMFS
spokeswoman Teri Frady.

Shaw said her analysis of harbor seal tissue samples from Maine, Cape
Cod and New York showed high BFR levels.

"They are loaded with chemicals," Shaw said. Some evidence suggests BFRs
could disrupt thyroid hormones and cause psychological and other
long-term disorders, including cancer.



A dubious breakthrough
BFRs were an ingenious chemical discovery back in the 1960s. The bromine
in the polybrominated diphenyl ethers (PBDEs) that are known
collectively as BFRs combines aggressively with hydrogen atoms, robbing
fire of an essential ingredient. That's why bromine is used in chemical
fire extinguishers. By combining bromine ethers with highly flammable
plastic, such commonplace items as computer housings, mattress foam and
chairs now contain a built-in fire suppressant that helps them meet fire
codes.

"The chair you're sitting in is probably 5 percent BFR," said
Christopher Reddy, a chemical oceanographer at the Woods Hole
Oceanographic Institution. BFRs make up between 5 and 50 percent of the
material in our household products. Their molecules mimic one of the
essential molecules produced by our thyroid gland.

"Think of them as keys into the keyhole of some molecular process in the
body," Reddy said. "It throws a wrench into the system."

Unfortunately, BFRs do not stay put. They are constantly entering the
environment as molecules sloughed off the material, or when
BFR-containing items are broken up during disposal. They've been found
everywhere, from remote Arctic regions to whales that stay far out to
sea.

BFRs are extremely stable. They linger in dust, or travel with water,
ultimately winding up in the ocean. There they latch on to microscopic
plankton and start up the food chain, as bigger fish eat smaller fish
with the chemicals stored in fatty tissue. At the top, are large
predators, like seals, and us, eating cod, hake, pollock, and other
large fish.



Canaries in the coal mine?
Shaw, the executive director of the Marine Environmental Research
Institute in Blue Hill, Maine, is concerned that seals may just be our
canaries in the coal mine. BFRs were first detected in human breast milk
in the 1970s in Sweden, where levels tripled over 20 years. U.S. breast
milk shows levels 100 times that in Sweden.

Shaw and others believe high levels of chemicals in the body could lower
the immune system responses in seals and in humans, making them more
susceptible to diseases.

Alternatives do exist. There are three plastics that are
self-extinguishing, but don't contain BFRs. Natural flame-resistant
materials like leather, metal and glass could also be used, and design
changes to products could make them less flammable. The BFR industry has
already phased out the two most toxic forms of the chemical, but is
resisting a ban on the most prevalent compound, known as deca-BDE.

Shaw said her research helped with Maine's recent decision to ban BFRs
as of 2010. Washington state has a similar ban, and nine other states,
including Massachusetts, have legislation filed to enact one.

"We do still have a large inventory in homes and offices that will be
here for a while," Reddy said.

Doug Fraser can be reached at dfraser at capecodonline.com.



When will it end?

In the 1960s it was DDT and PCBs; now brominated flame retardants, or
BFRs, are causing alarm.


All three chemical compounds are very resistant to being broken down by
sunlight, heat, moisture and other factors in the natural environment.
Modern chemists are looking to make new compounds that have a so-called
fuse, an Achilles' heel that breaks the compound down into more natural,
biodegradable components.


Deborah L. DeBiasi
Email:   dldebiasi at deq.virginia.gov
WEB site address:  www.deq.virginia.gov
Virginia Department of Environmental Quality
Office of Water Permit Programs
Industrial Pretreatment/Toxics Management Program
Mail:          P.O. Box 1105, Richmond, VA  23218 (NEW!)
Location:  629 E. Main Street, Richmond, VA  23219
PH:         804-698-4028
FAX:      804-698-4032