Pesticide Impacts on Polar Bears Prompt Group to Sue EPA

All pesticides in the United States must be registered by the EPA before they can be lawfully used. Courts have held that the agency must examine the impacts of any pesticide it approves on federally protected endangered species.

The polar bear was formally listed as a threatened species under the Endangered Species Act on May 15, 2008, following a petition and litigation by the Center for Biological Diversity, but the EPA has yet to examine the impacts of any approved pesticide on the species.

"The pesticide crisis is a silent killer that threatens not only the polar bear but the entire Arctic ecosystem and its communities," said Rebecca Noblin, a staff attorney with the Center for Biological Diversity in Anchorage, Alaska.

Young polar bears play at Nuwuk, Alaska. (Photo by Ignati)

"The benefits of protecting the polar bear from pesticide poisoning will reverberate throughout the entire Arctic ecosystem, with positive impacts for Arctic people, who share the top of the food pyramid with polar bears," Noblin said.

Pesticide contamination in the Arctic is primarily due to sources outside the Arctic, including the Lower 48 states, the lawsuit claims.

Four primary pathways appear to exist for the transport of contaminants to the Arctic ecosystem: atmospheric transport, ocean currents, transpolar ice pack, and large Arctic rivers, according to reports cited in the lawsuit from the Arctic Monitoring and Assessment Programme, a working group of the Arctic Council.

These pesticides are biomagnified with each step higher in the food web, reaching some of their greatest concentrations in polar bears, the apex predators of the Arctic, said Tanya Sanerib of the Crag Law Center, an attorney on this case.

Pesticides have been linked to suppressed immune function, endocrine disruption, shrinkage of reproductive organs, hermaphroditism, and increased cub mortality in polar bears.

Human subsistence hunters in the Arctic, who share the top spot on the food web with the polar bear, also face increased risks from exposure to these contaminants, Sanerib said.

"The United States has lagged far behind the international community in taking action to protect the species and people of the Arctic from pesticides and other contaminants," said Noblin. "But the listing of the polar bear under the Endangered Species Act gives the EPA both the opportunity and the obligation to meaningfully address the poisoning of the Arctic."

In addition to pesticide contamination and loss of their sea ice habitat from global warming, polar bears face threats from increased oil and gas development in their habitat and the proliferation of shipping routes in an increasingly ice free Arctic. The Center maintains that these activities threaten polar bears with the heightened risk of oil spills as well as rising levels of noise pollution and other kinds of human disturbance.

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