Five hundred miles of windswept tundra separate the pristine polar wilderness surrounding Nunavut from its closest polluting neighbor. Despite the Canadian territory's remote geography in the Eastern Arctic, a new study shows Nunavut is on the receiving end of a wind-generated dioxin pipeline that originates thousands of miles south of the province.
In the first continentwide study to trace dioxins from source to destination, an international research team has identified US facilities that contributed 70 to 82 percent of dioxin deposited in eight locations across Nunavut.
Dioxins are trace chemicals produced by burning such things as municipal and medical waste. Introduced into humans through consumption of animal fats, they are thought to produce a range of health problems. But, at low concentrations, these health effects remain uncertain.
Nunavut's people have up to two times more dioxin in their system than residents of southern Canada. Dioxins enter the Nunavut food chain as they settle from the air onto lichens, mosses, and shrubs eaten by caribou - a primary food source - and through algae and fish eaten by seals and walruses - another major food source.
To track the migration of dioxins to these remote locations, researchers - headed by Barry Commoner of Queens College, New York - used sophisticated air-transport models developed by the National Oceanographic and Atmospheric Administration to simulate the spread of radiation from a nuclear disaster. Using pollution data from 44,091 sites across North America, plus meteorological and chemical information, the researchers created a model that tracked dioxin movement by the hour for a full year.
The results are highly specific. In the case of Nunavut's Coral Harbor collection point, 19 of the 44,000 sources account for one-third of the deposits there. "Our model allows you to identify specific sources, which is the only way to remedy the situation," Dr. Commoner says. "You can't put an umbrella over Nunavut or stop them eating contaminated food - so to deal with the problem you have to go to the source and either eliminate or reduce the emissions."
Commoner says the goal of the study is to provide hard data for making policy decisions. "We help the community solve environmental and energy problems by doing the necessary scientific research. We use a model that allows you to do that: identify the source and do something about it."
(c) Copyright 2000. The Christian Science Publishing Society