Artic pollution

Undated photo provided by the journal Science shows ponds containing fallen contaminants from seabird guano in the Canadian high arctic. A major source of chemical contamination in the Arctic turns out to be _ bird droppings. Wind currents and human activities have long been blamed for fouling the pristine Arctic .

But a study by a group of Canadian researchers found that the chemical pollution in areas frequented by seabirds can be many times higher than in nearby regions. (AP Photo/Mark Mallory, Science)