"Some Arctic people are among the most highly exposed people on the globe because contaminants accumulate in their foods," the Norwegian-based group, a unit of the inter-governmental Arctic Council, said.

The report, presented at an Arctic environment pollution conference in the Finnish town of Rovaniemi, found mercury levels in some Arctic indigenous people are high enough to affect children's development.

It also said mercury levels in some wildlife are increasing while global emissions are not falling.

"Most of these contaminants are produced and used outside the Arctic," AMAP chair Helgi Jensson said in the report, prepared over the past five years by scientists from Arctic countries working with Arctic indigenous peoples.

AMAP said the Inuit in Greenland and Canada, the indigenous people of the Arctic, have among the world's highest exposures to certain toxic chemicals carried there from far afield.

People with increased risk mainly lived in areas with high intake of marine mammals, such as the Inuit, and those with high intake of some fish species, such as Yup'ik in western Alaska.

"They eat the food because it is full of nutrition but the the animals they eat are also contaminated. That's the dilemma," AMAP Executive Secretary Lars Otto Reiersen told Reuters.

He said the lack of elder animals in some populations may be a consequence of pollutants gathered in the Arctic from afar.

"Levels of PCBs in some wildlife are high enough to cause subtle effects on the immune system and this may even be true for children in some areas. Other PCB-risks include effects on brain development and reproduction," AMAP said.

PCBs, or polychlorinated biphenyls, are mixtures of chemicals and potentially cancer-causing. They build up in the food chain, especially in fatty tissue like blubber - key nutrition for polar bears and the Inuit. Use of the industrial chemicals is largely banned in the West.

"In the long-run, international conventions or protocol are the only ways to reduce the contaminant load in the Arctic traditional foods and thus in people. However, it will take many years before levels decrease, and in the short-term dietary advice may also be prudent," AMAP said.

Marine mammals, such as polar bear, Arctic fox, harbour porpoise, seals, and birds also suffered from high levels of contamination by persistent organic pollutants (POPs) that damage the nervous system, development and reproduction.