Fire retardants found in killer whales
SEATTLE — Fire retardants used worldwide in manufacturing vehicle parts and computers have been found in Puget Sound orcas, raising new concerns about the long-term health of the region’s killer whales, a new Canadian study shows.
Canadian fisheries scientists found that that killer whales they tested had troubling levels of polybrominated diphenyl ethers or PBDEs, chemicals related to PCBs, a carcinogen banned decades ago.
“Killer whales may be one of the first species that really sounds the alarm to the risks that these types of chemicals may pose,” said Peter Ross, a marine mammal toxicologist for Canada’s Department of Fisheries and Oceans.
The study was published in the Aug. 15 edition of Environmental Science and Technology, a magazine of the American Chemical Society.
The findings come as the state Ecology Department prepares recommendations for curtailing the use of PBDEs in Washington, following an executive order Gov. Gary Locke issued in January.
Ecology spokeswoman Sheryl Hutchison said an advisory committee expects to issue a draft report in about three weeks.
Traces of industrial-strength fire retardant also have turned up in wild and farm-raised salmon around the world, a study earlier this month showed. Northwest chinook salmon are a staple of killer whales’ diet.
The toxicity of PBDEs isn’t fully understood, but the chemicals can harm neurological development and function in babies and young children.
Studies have shown levels of PBDEs are doubling in humans every two to five years, with levels in North America 40 times higher than the rest of the world.
PCBs have been banned since the 1970s, but PBDEs remain in production around the world. Bans in Europe, California and Maine will take effect during the next few years, and U.S. manufacturers voluntarily are stopping production of some forms of the fire retardant.
The marketing of PBDEs — used in common household and workplace items like computers, foam furniture cushions and synthetic fabrics — began in the 1980s, Ross said. Their detection in orcas indicates how pervasive the toxins are in the environment, he added.
Canadian researchers between 1993 and 1996 analyzed skin and blubber samples from about 40 living killer whales. Samples were taken from transients that migrate along the Pacific Coast, Northern residents between north Vancouver Island and southeast Alaska, and Southern residents that occupy waters between south Vancouver Island, coastal Washington and Puget Sound.
A study four years ago found transients and Southern resident orcas had higher PCB levels than Northern residents.
The latest study revealed PBDEs in about 1 part per million milligrams of fat, Ross said, with levels of the chemicals relatively constant among all three groups.