On a remote Alaska island, toxic chemicals have found their way into the food chain.
Recent results from an ongoing study find that the people and animals of St. Lawrence Island have high levels of chemicals, raising questions about the safety of traditional foods like walrus and seal, as well as the lingering effects of long-abandoned military bases.
St. Lawrence, with its rolling hills and Cold War military history, sits just south of the Bering Strait. Closer to Russia than to Alaska, it is home to two villages -- Savoonga and Gambell, where many of the more than 1,400 residents depend on subsistence to make ends meet.
As remote as the island is, toxic chemicals have found their way into the food chain.
In a study of 120 people on the island, testing found polychlorinated biphenyls (PCBs) at levels four to eight times higher than average U.S. levels, said Dr. David Carpenter, director of the University of Albany at New York's Institute for Health and the Environment, in a recently released study. Carpenter also tested a sampling of animals villagers depend on, including bowhead whales, finding that they too have very high levels of PCBs.
Residents wonder if this explains what seems to be a high rate of cancer in the two villages. "Pretty much every house we go to has a person with cancer, a person that has had cancer, or a person that has died of cancer," said Savoonga Mayor Jane Kava, who has worked as a health researcher on the island.
Carpenter said that PCB levels are high in the Arctic because of the colder temperatures. While PCBs are present all over the world, in colder temperatures they condense from the air to the land and water, where they then enter the food chain.
Also of interest to Alaskans, Carpenter's past work has found important facts about the level of PCBs in farmed salmon compared to wild salmon. "On average, farmed fish have 10 times the contaminants of wild fish," he said. "We concluded that you could eat only one meal of farmed salmon every five months without increasing your risk of cancer."
PCBs are manmade chemical compounds that were used in paints, transformers, insulation and other industrial products until their ban in 1979. Past studies have shown that overexposure to PCBs can lead to cancer, diabetes or heart diseases, as well as problems with the thyroid and sex hormones. Carpenter said in an interview that girls exposed to PCBs reach puberty sooner than they would normally, and that men exposed to PCBs experience decreased levels of testosterone.
On St. Lawrence Island, Carpenter had been trying to compare the various animals and fish around the island to determine which are the safest to eat. "We had hoped that we could provide information on which animals were safest, but the problem was that all the animals had very high levels," he said.
Because of the health benefits of Native foods, especially the omega-3 fatty acids found in fish, he said, "We can't really answer the question of the risks versus the benefits of eating these foods, although one thing we can say, and this is troubling, there's no evidence that these healthy foods reduce the risk of cancer."
Carpenter said that studying the relative risks would be the next phase of the study.
In New York, Carpenter studied PCB levels in fish such as perch and northern pike, an important supply of food for the Mohawk tribe that lives in that part of the country. When he reported the high levels of PCBs, "people stopped eating fish and started eating Big Macs, which is why I'm extremely careful about telling people what to eat."
Pamela Miller, executive director of Alaska Community Action on Toxics (ACAT), said in an interview that she believes the high levels of PCBs on St. Lawrence Island originate from two former military bases. The bases were used during the Cold War era. ACAT has tested the soil, air and water and found not just PCBs, but also heavy metals like mercury and lead, Miller said.
"St. Lawrence Island was used as the eyes and ears during the Cold War, because of its proximity to the Soviet Union," Miller said.
The new study builds on past work by both Carpenter and Miller's ACAT. A 2002 study of about half as many people also found high rates of PCBs in people and animals.
While it's worrisome for residents to hear that PCB levels still remain high on St. Lawrence Island, Mayor Kava said at least the problem is being monitored and villagers are being kept informed.
"I think everybody was a little bit shocked, but people wanted to know what levels they had in their body, so even if they were high at least they knew," said Kava.