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Norwegian killer whales most toxic mammals in Arctic




Norwegian killer whales most toxic mammals in Arctic


DetoX
Toxic chemicals: a threat to wildlife and animals

Norwegian killer whales most toxic mammals in Arctic
WWF News Release
December 12, 2005

Gland, Swtizerland – Initial scientific results show Norwegian killer whales are the most toxic mammals in the Arctic, says WWF, the global conservation organization.

Previous research awarded this dubious honour to the polar bear, but a new study shows that killer whales have even higher levels of PCBs, pesticides and a brominated flame retardant.

The results are based on blubber samples taken from killer whales in Tysfjord, a fjord in arctic Norway. This is the first time the findings of the research, carried out by the Norwegian Polar Institute (NPI), and partly funded by the Norwegian Research Council, have been revealed.

“Killer whales can be regarded as indicators of the health of our marine environment,” said Dr Hans Wolkers, a researcher with NPI.

“The high levels of contaminants are very alarming. They clearly show that the arctic seas are not as clean as they should be, which, in particular, affects animals at the top of the food chain.”

Killer whales are found throughout arctic Norway, including Svalbard and the Barents Sea, but congregate in the Tysfjord area to feed on spawning herring during the winter. This offers an excellent opportunity to sample them in an efficient way.

WWF funded Dr Wolkers to carry out new research from this November to further monitor the levels of dangerous contaminants in the killer whales, including another brominated flame retardant called deca-BDE, used in electronic goods and coatings for household products such as carpets. The findings of this research are expected next year.

The appearance of a potentially dangerous brominated flame retardant in killer whales is of particular concern, because – unlike PCBs and the most harmful pesticides – most hazardous brominated flame retardants are not currently banned. Brominated flame retardants can affect the animals’ neurological function, behaviour and reproduction.

“This new killer whale research re-confirms that the Arctic is now a toxic sink,” said Brettania Walker, a toxics officer with WWF’s International Arctic Programme.

“Chemicals in everyday products are contaminating arctic wildlife. The European Council of Ministers, due to vote on REACH on December 13th, must agree to the replacement of all hazardous chemicals with safer alternatives whenever these are available.”




A spyhopping Orca in the Ross Sea. Image by Jaime Ramos, U.S. Antarctic Program, National Science Foundation.

“The toxic contamination of killer whales clearly shows the result of an unsustainable use of chemicals internationally,” added Helen Bjørnøy, the Norwegian Minister of Environment. “This is one of the greatest global environmental threats. The EU ministers now have the possibility to strengthen the chemicals legislation in Europe, and I urge them to use it. It is imperative that the REACH regulation becomes a tool to stop using the most dangerous chemicals.”

END NOTES:

• Killer whales are particularly vulnerable to contaminants because they feed at the top of the food chain and therefore accumulate contaminants from the species they prey on. These contaminants accumulate in their blubber and other fat-rich tissues. Killer whales can live up to 40 years so can have very high contaminant levels in their tissues. Toxin levels increase moving up the food chain (a process called biomagnification) and are highest in top predators, such as polar bears.

• Blubber samples were taken from ten male killer whales from Tysfjord, Norway in November 2002. They were later tested for PCB 153, toxaphene, chlordane, DDE, and PBDE 47. They showed higher levels of these chemicals compared to Svalbard polar bears and harbor seals and beluga whales from Svalbard and the Gulf of St. Lawrence, Canada.

• The PBDE (polybrominated diphenyl ethers) class of brominated flame retardants is structurally similar to PCBs and exponential increases of PBDEs have been documented in wildlife and humans in recent years. PBDEs are used in electrical equipment, construction materials, coatings, textiles and polyurethane foam.

• The PBDE brominated flame retardant detected in the Norwegian killer whales sampling was 2,2′,4,4′-tetrabromodiphenyl ether, also called PBDE 47. PBDE 47 is often studied due to its persistence and ability to bioaccumulate. Studies in mice have linked neonatal exposure to PBDE 47 to permanent alterations in spontaneous behavior.

• Many pollutants of concern in the Arctic were not produced or ever used in the Arctic. Instead, chemicals from everyday household products and industrial and agricultural chemicals from other areas of the world travel great distances via air and water currents to finally end up in the Arctic. Long, dark winters and cold temperatures inhibit the breakdown of chemicals in the Arctic.

• REACH (Registration, Evaluation and Authorisation of Chemicals) is the draft EU law that should lead to the identification and phasing out of the most harmful chemicals. If it becomes law it will be enforced in all countries in the European Union. REACH will also lead to changes in chemical regulation and production outside the European Union. The current EU chemical regulatory system, similar to others around the world, considers chemicals “safe until proven otherwise”.



Killing killer whales with toxics

By Claire Doole
12 Dec 2005




DetoX
Toxic chemicals: a threat to wildlife and animals

The flaming orange and pink hues of the arctic sun spill across the glassy waters of the fjord, granting the perfect conditions for spotting killer whales, the ocean’s top predator. Each year, hundreds of these whales, with their distinctive black back and white underbelly, flock into Tysfjord and Vestfjord off the north coast of Norway in the Barents Sea between November and January to feed off migrating herring.

Killer whales, or orcas, hunt everything from fish and up — walruses, seals, sea lions, penguins, squid, sea turtles, sharks, and even other kinds of whales. Hunting in packs, they are often referred to as the “wolves of the sea”.

But here in the Norwegian arctic, these whales feed mainly on schools of fish that come in close to shore. So close, that they have attracted many tourist boats who can watch the whales from only metres away. Whale watching is big business in an area where incomes are comparatively low for oil-rich Norway. But the season is short, with the sun setting in early December and not rising again until a month later. Despite the unpredictable weather, many still make the journey to see these “killer” marine species.

However, Hans Wolkers, a straight talking and resolute Dutchman has not come to whale watch but to whale dart. A toxicologist with the Norwegian Polar Institute, he is in Tysfjord to take biopsy samples of orca blubber to test for toxic contamination. It is his second visit and he is under no illusion about what he is going to find.

“Several years ago I took away ten samples for testing and the results were shocking,” Wolkers explained. “All ten showed consistently high levels of toxins. You name it, the whales had it – PCBs, pesticides and at least one type of brominated flame retardant. They are the most toxic mammal in the Arctic.”

Arctic sink

To date, it has been the polar bear that had the dubious honour of being the most toxic mammal of the Arctic. But Wolkers’ research shows that orcas outstrip the bear in terms of pesticides and one type of brominated flame retardant, in addition to the high levels of the toxic, persistent chemicals PCBs (polychlorinated biphenyls).

According to Wolkers, the appearance of a brominated flame retardant, a type of chemical found in every day articles such as computers, is particularly worrying because unlike PCBs and the most harmful pesticides, most are not currently banned.

Although many PCBs and pesticides have been phased out over the past twenty years and officially banned since the Stockholm Convention on Persistent Organic Pollutants (POPs) came into force in 2004, these persistent pollutants, as their names suggest, are particularly difficult to get rid of. In the Arctic, where temperatures are routinely below freezing and the winters are steadfastly dark, they take even longer to break down. To make matters worse, due to the northerly direction of air and water currents, most of Europe’s pollution ends up in the Arctic.

“The Arctic serves as a global environmental indicator, an early warning system with which we can gauge the health of the planet,” explained Rasmus Hansson, CEO of WWF-Norway. “This remote region, far from the centres of industrialization, has become the world’s toxic sink.”

Gazing at the fjords bathed in winter sunlight, where snow-capped peaks rise sheer and straight from the southern Barents Sea, it is difficult to believe that the Arctic is so contaminated. However, the chemicals transported by air and sea have for decades been contaminating the top predators of the food chain.

“Killer whales are particularly vulnerable to contaminants because they feed at the top of the food chain and accumulate contaminates from the species they prey on,” said Brettania Walker, a toxics officer with WWF’s Arctic Programme. “These contaminants accumulate in their blubber over time. As killer whales can live up to 40 years, this means they can have very high contaminant levels in their tissues.”

In pursuit of the toxic whale

When not testing herring — which is known to have some levels of toxins but is still safe to eat — Wolkers spends days at sea going after the killer whales. This is certainly not as easy as catching herring as the whale spends most of its time underwater, surfacing for less than a couple of seconds at a time. In choppy Arctic waters, coupled with bad lighting, the plume of spray from the whale’s breathing hole is practically invisible to the untrained eye. They are also extremely fast.

“A pod of whales travel on average 25 kilometres a day, but some can do 70 kilometres,” marvelled Tiu Simila, a marine biologist who has been studying the behaviour of the Tysfjord whales for the past 18 years. “Streamlined like torpedoes, they can easily outrun a motorboat.”

But, these factors don’t deter them from their WWF-supported mission. Wolkers and his driver-cum-darter, Odd Petter Hovde, a softly spoken Norwegian who also pilots whale watching boats, have too much respect for the whales to chase or confront them head on. They are biding their time, scanning the horizon for a glimpse of the distinctive upright dorsal fin.

“It is impossible to dart them when they are travelling,” explained Hovde. “We look for the birds circling overhead and then we know that the whales are about to feed. That is the time when they are distracted. That is the time to take aim.”

After several hours of false alarms and mounting frustration with the whale watching boats tracking them, Wolkers and Hovde finally came upon some whales about to feed. Killer whales employ a range of tactics to capture their herring prey, such as feeding off the discarded catch of fishing boats. But one of the most spectacular techniques they employ is “carousel feeding” when they herd the herring into tight shoals close to the surface and then stun them with their tails. The herring are often so frightened they jump out of the water in sheer panic. It is then that the feeding frenzy begins.

Picking up the biopsy gun, with the assurance of a man who has spent time in the Norwegian army, Hovde takes aim.

“The trick is to get within 20m and dart it on the side under the dorsal fin as this is the biggest surface area to hit,” Hovde explains.

Despite hours of maneuvering and coming within range, the conditions were not right this trip out. The dart, which is hollow, got entangled in the barrel of the gun and despite frantic attempts to re-assemble, it was too late. The whales had moved on.

However, patience and tenacity paid off. At the end of two hard weeks, braving the cold and fast fading light, Wolkers in the end collected blubber samples from nine females and five males. This means he can test for the toxins passed on from lactating mothers to calves. Marine mammals produce milk that has 30 to 70 per cent fat so their young are exposed to high amounts of contaminants at a vulnerable time in their development.

Whale detox

In addition to testing for all sorts of toxics cocktails found in orcas, the tests will look for a particular brominated flame retardant called Deca-BDE, used in plastics, electronic goods and coatings for household products such as carpets and other upholstered fabrics. They will also analyze the blubber samples for vitamin A levels, which can indicate whether the toxins are impacting on vital systems such as hormones.

“Although Deca-BDE is a suspected neurotoxin that could affect foetal development, it is not banned anywhere in the world,” stressed WWF’s Brettania Walker. “This new killer whale research underlines the need for all hazardous chemicals to be replaced with safer alternatives when they are available.”




DetoX
Toxic chemicals: a threat to wildlife and animals

WWF is currently campaigning for EU legislation known as REACH (Registration, Evaluation and Authorization of Chemicals) which would lead to the identification and phasing out of the most harmful chemicals. The current EU chemical regulatory system, similar to others around the world, considers chemicals “safe until proven otherwise”.

According to Walker, REACH should have an impact not just in Europe but also worldwide as chemical imports would have to meet high safety standards. While it is known that PCB’s, pesticides and brominated flame retardants can affect the nervous, hormone and immune systems of people, little is known about the impact of these chemicals on the health of the killer whale and other marine species.

Recent studies have shown that concentrations of brominated flame retardants are already doubling their concentrations in the environment every five years. Time is of the essence to find out more about these bio-accumulating toxins before it’s too late.

“As the migratory pattern of the herring changes, the whales have begun to move offshore into deeper waters,” noted Tiu Simila. “This means we will soon lose an opportunity to find out more about their behaviour and the impact that contamination is having on their health.”

Since the killer whales first came to Tysfjord, they have given us an unprecedented glimpse into their natural world. Unfortunately, our parting gift to them, as they move back to the ocean, is more of a poisoned chalice, a toxic burden whose lethal consequences are not yet known.

* Claire Doole is Head of Press at WWF International

END NOTES:

• The Orca (Orcinus orca) is the largest member of the dolphin family. It is found throughout the world’s oceans, but tends to prefer the cooler, more productive polar and temperate waters. Like all dolphins, orcas use sophisticated biological sonar, called echolocation and can swim up to 50kph and travel 120-160 kilometres per day. Males can be up to 9.5m long and weigh in excess of 6 tons. Females are smaller, reaching up to 8.5m and weighing about 5 tons.

• The Stockholm Convention is a global treaty to protect human health and the environment from persistent organic pollutants (POPs); chemicals that remain intact in the environment for long periods, become widely distributed geographically, accumulate in the fatty tissue of living organisms and are toxic to humans and wildlife. POPs circulate globally and can cause damage wherever they travel. In implementing the Convention, governments will take measures to eliminate or restrict the production and use of the selected POPs.

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