Whales Face New Peril, Study Says

Sunday, October 24, 2004
VICTORIA, BC - Killer whales in B.C. and Washington state waters may be contaminated with high levels of fire-retardant chemicals, a new study suggests.

Early results from a study by marine mammal toxicologist Peter Ross show relatively high levels of polybrominated diphenyl ethers, or PBDEs, in harbour seal pups.

Harbour seals were used as surrogates for orcas in the study because they are easier to catch. Like whales, they are fish-eaters at the top of the food chain.

"Harbour seals tell us a concise story about environmental contaminants in our coastal waters," said Ross, who works for the Department of Fisheries and Oceans at the Institute of Ocean Sciences.

The study is more bad news for orcas. The fact that harbour seals are contaminated with flame-retardant chemicals suggests killer whales are equally vulnerable to contamination because both eat a diet of fish, said Ross.

Transient killer whales, on the other hand, are likely to have even higher levels of these flame-retardant chemicals because they also eat harbour seals.

"I'm waving a yellow flag. PBDEs are a concern in many parts of the world. But we in B.C. have a special concern -- the plight of the killer whales," said Ross.

A 10-year-old study of PBDEs in killer whales showed low levels -- about two per cent of the concentration of PCBs -- of the toxic chemical. Preliminary results from the 2003 study show PBDEs are now a major contaminant of harbour seals and likely of killer whales too.

"Things have gotten worse for killer whales in the last 10 years," Ross said.

He obtained his samples capturing seal pups at Victoria, off Hornby Island, in Queen Charlotte Strait, near the Vancouver Airport, south of San Juan Island, and in Puget Sound. He took blood, blubber, skin and stool samples, then released the pups back to the wild.

The toxicologist is concerned that PBDEs, which are suspected of causing birth defects, thyroid disease and developmental defects in human beings, will threaten the reproductive health of killer whales. The small population of 83 southern resident killer whales living off the coasts of B.C. and Washington state is already endangered.

They breed in isolation. They're high in the food chain. They're long-lived. They're threatened by heavy vessel traffic, including navy vessels with sonar and remote sensing. They're also affected by the availability of salmon.

"We should be worried about their health, how these chemicals affect their reproduction and immune systems and their growth and development," Ross said.

He has seen elevated mortality rates and reduced reproduction in the killer whale population but can't draw a direct link to chemicals in the environment.

"It's exceedingly difficult to establish cause and effect with wildlife. If we look at the contamination concentration we find in killer whales, the weight of evidence suggests they are at risk for adverse health effects and are less well-equipped to deal with their natural environment."

In 1999, Ross made international news with research showing B.C.'s killer whales are among the most contaminated animals on the planet. Ross found some orcas have PCB levels 250 times higher than those in human beings.

Cancer-causing PCBs, which were used in electric transformers and as industrial lubricants, have been banned since 1977.

PBDEs, found in furniture, plastics, automobiles, computers, electronics and insulating material, are still in production around the world. PBDEs are not thought to be as toxic as PCBs, but they are structurally similar. PBDEs leach into the environment at dumps and manufacturing facilities.

They accumulate in the fatty tissues of human beings and animals. They're found in household dust, and a recent Northwest Environment Watch study testing the breast milk of 40 nursing mothers found the chemical in all 40 samples.

The European Union and California have banned their use. Major manufacturers such as IKEA, Intel and Sony are choosing less dangerous alternatives.

In January, Washington Gov. Gary Locke announced he would address the growing threat of PBDEs. Maine is also considering a ban.

In Europe, reducing the use of flame retardants led to declining PBDE levels in breast milk.

Canada is assessing the environmental and health effects of the chemicals. In May, an Environment Canada draft report found an increase of PBDEs since the early 1990s. It also found levels in some areas "may pose a risk to the development of some wildlife and invertebrates."

The department is working with industry, preparing a plan to minimize the effect of PBDEs on the environment.

"Canadian society has to decide if it's important," said Ross.

Ross's $250,000 study received $100,000 from the Fisheries Department's environmental sciences strategic research fund. Locke's office and the Department of Fish and Wildlife have contributed $80,000.

American researchers worked with Ross at capture sites in Puget Sound. B.C.'s Ministry of Water, Land and Air Protection gave $10,000 for seal research. Federal species-at-risk funding contributed $50,000.

Ross will give a speech Monday at 7:30 p.m. at Swan Lake Nature Centre on the toxic loads in the region's marine mammals. The event is hosted by the Victoria Natural History Society.

His study, with complete results, will be published in the spring of 2005.