Tag Archives: polybrominated diphenyl ethers

Some toxic chemicals increase; others decline in Puget Sound fish

The importance of long-term environmental monitoring is driven home in a new study by toxicologists who have spent years examining chemical contamination in Puget Sound fish.

English sole sampling locations include both urban and rural areas of Puget Sound.
Archives of Env. Contamination and Toxicology

After 28 years of monitoring, researchers have confirmed that it is extremely difficult to remove polychlorinated biphenyls (PCBs) from the Puget Sound food web. In some locations, PCBs are actually increasing in bottom fish some 38 years after these chemicals were banned in the United States.

“Across the board, we’ve seen either no decline or even increases in our English sole, which is really kind of shocking considering all the remediation that has been going on,” said Jim West, a toxicologist with the Washington Department of Fish and Wildlife who I interviewed for a story in the Encyclopedia of Puget Sound.

The report, published in the Archives of Environmental Contamination and Toxicology, provides some bleak news about PCBs, but there are hopeful signs for other chemicals. For example, researchers were pleasantly surprised to find that toxic flame retardants containing polybrominated diphenyl ethers seem to be disappearing rapidly from the ecosystem less than a decade after the most toxic forms of PBDEs were banned in Washington state.

The study went to some lengths to make sure the decline in PBDEs in Pacific herring was not related to other factors — such as size, since the average herring is getting smaller over time.

“I now feel like this is a solid trend, and that’s really exciting,” Jim told me. “I believe it is related to our efforts in source control.”

Of course, we wouldn’t know about these long-term trends in chemical contamination were it not for long-term monitoring efforts. I discussed the importance of monitoring with Sandie O’Neill, a research scientist with WDFW. She is an author of the new study along with Jim West and Gina Ylitalo of NOAA’s Northwest Fisheries Science Center. See the related story “Monitoring helps to reveal hidden dangers in the food web” in the Encyclopedia of Puget Sound.

“We are changing people’s perspectives about contaminants throughout the (Puget Sound) watershed, including how such contaminants get into the food web,” Sandie told me.

As Sandie describes it, monitoring is needed in many aspects of ecosystem health. It can tell us whether nature is healing itself and whether restoration projects by humans are improving fish and wildlife habitat as well as human health.

EPA deal waves good-bye to toxic flame retardants

Negotiations between the Environmental Protection Agency and manufacturers of toxic flame-retardant chemicals will result in a three-year phase-out of the last polybrominated diphenyl ether, the deca form.

Steve Owens, EPA’s assistant administrator in the Office of Prevention, Pesticides and Toxic Substances, had this to say in a news release today:

“Though DecaBDE has been used as a flame retardant for years, U.S. Environmental Protection Agency has long been concerned about its impact on human health and the environment. Studies have shown that decaBDE persists in the environment, potentially causes cancer and may impact brain function. DecaBDE also can degrade to more toxic chemicals that are frequently found in the environment and are hazardous to wildlife.

“Today’s announcement by these companies to phase out decaBDE is an appropriate and responsible step to protect human health and the environment.”

Alarms bells have been sounding over PBDEs for several years. Concerns relate to liver and thyroid disease, neurological development and potential effects on the immune and reproductive systems.

Because they are persistent in the environment, these chemicals have been accumulating in the tissues of the familiar killer whales that frequent Puget Sound and the Salish Sea. See the story I wrote about toxics in orcas, October 2007.

Deca is used to reduce the risk of fire in electronics, textiles, automobiles and other applications, but other alternatives have been identified.

Today’s announcement relates to agreements with the two U.S. producers of decaBDE — Albemarle Corporation and Chemtura Corporation — along with the largest U.S. importer, ICL Industrial Products, Inc.

Under the new agreements, the companies will end production, importation and sales of decaBDE for most uses in the United States by December 31, 2012, and to end all uses by the end of 2013. Here are the letters of commitment:

Albemarle Corporation (PDF 403 kb)
Chemtura Corporation (PDF 34 kb)
ICL Industrial Products, Inc. (PDF 55 kb)

Brian Carter, global business director of Albemarle’s flame retardant group, made this comment in a prepared statement:

“While hundreds of science-based and peer-reviewed studies have shown Deca-BDE to be safe in use and one of the most efficacious flame retardants in the world, Albemarle is committed to delivering safe and effective products with increasingly smaller environmental footprints.

“Safe and environmentally sound substitutes for decabrom are available today, and we are working with our customers and the Environmental Protection Agency to implement a phase out of Deca-BDE in the coming years.”

Tony Parnell, vice president of Albemarle’s polymer solutions division, added this comment:

“In addition to our existing alternatives, Albemarle fire safety scientists have developed GreenArmor, a polymer-based flame retardant technology which is a recyclable and an eco-friendly alternative to current decabrom technology.

“Our investment in this new fire safety technology demonstrates Albemarle’s commitment to constantly seek higher-performing, sustainable alternatives to existing fire safety products.”

Meanwhile, the state of Washington remains on track to phase out PBDEs —with deca being the only one remaining. I was wondering how EPA’s agreement would mesh with Washington state’s requirements, so I called Curt Hart at the Department of Ecology.

“It is not an exact match, but it is very close,” Curt told me. “We are very pleased with the agreement that EPA has reached with these manufacturers. The good thing is that everyone now recognizes that deca is a problem as well (as other PBDEs).”

Visit Ecology’s Web site for the state’s phase-out schedule, including an important report called “Alternatives to Deca-BDE in Televisions and Computers and Residential Upholstered Furniture.”

Watching for the effects of toxic flame retardants

Whenever I write about toxic flame retardants known as polybrominated diphenyl ethers, or PBDEs, I become more convinced that we have a problem, mainly because these chemicals do not tend to break down in the environment.

Evidence indicates they are being washed into streams and tend to accumulate throughout the food web, although the trend may be slowing or even declining in Washington state, which has banned most forms of PBDEs. (Review the Water Ways entry from April 2, with links to other information sources.)

OK, so they’re a concern. But are they really harmful?

Ongoing studies have linked the chemicals to neurological and developmental problems in mice and rats, which could have implications for humans as well as other mammals.

But an important new laboratory study, by researchers with the Canadian Wildlife Service, may be the first to link the chemical to reproductive problems in birds — and at concentrations actually found in the environment.

The researchers reported that the chemicals caused thinner egg shells for American kestrels, a predatory bird that has been declining in numbers in the eastern U.S. and Canada. Furthermore, egg laying was delayed for females fed the chemicals versus those that did not get it.

The levels that caused reduced egg viability have been found not only in wild kestrels but in herring gulls and peregrine falcons as well. I would think this would be a concern for all our predatory birds, if not other species as well.

Karen Kidd and Wendy Hessler discuss these findings in the latest issue of Environmental Health News. Guess what the magazine titled their article: “Are flame retardants the next DDT?”

That refers, of course, to the chemical Dichloro-Diphenyl-Trichloroethan. Before it was banned, DDT became linked to thinning eggshells in eagle nests. DDT failed to break down readily in the environment, contaminating the entire food chain and playing a major role in the creation of the Endangered Species Act.