Univeristy of Alberta ecologist David Schindler holds an example of a deformed fish found in the Athabasca watershed. (CBC)

Pollutants from the Alberta oilsands are damaging fish in the Athabasca River, say scientists and First Nation representatives.

They're showing the public examples of deformed fish caught in the northern river over the last few years, at the University of Alberta's Lister Centre in Edmonton.

Fish with tumours, deformities and signs of disease or infection were collected from the lower Athabasca River, Athabasca Delta and Lake Athabasca, downstream from the oilsands.

University of Alberta ecologist David Schindler says the National Pollutant Release Inventory, Canada's legislated, publicly accessible record of pollutant releases and transfers, is proof of the harm caused by oilsands pollution going into the water.

"Embryos of fish exposed to oilsands' water and sediment have very high rates of mortality, and among the survivors, there are very high rates of deformities," Schindler said.

"I think most of you will agree they aren't things you'd like to find on your plate when you go to a restaurant."

In August, Schindler published a study in the Proceedings of the National Academy of Sciences documenting oilsands pollution in the waterways, a study disputed by both Alberta and the oilsands industry.

First Nations fishermen from Fort Chipewyan and Fort MacKay say deformed fish are becoming more and more common.

They worry about the viability of the fishing industry on Lake Athabasca, given their reluctance to eat or sell their catch.

Monitoring study needed: First Nations

"We live a very traditional life, we live off the land and the water. We have been told again and again that contaminants are naturally occurring, yet in the last 40 years we have seen the health of our community decline due to cancers and illness that we didn't see before," Chief Allan Adam of the Athabasca Chipewyan First Nation said in a statement.

"We need answers now about whether industry pollutants are related to declines in fish health and the health of our community."

They are sending a letter to Prime Minister Stephen Harper urging for an independent study on the health effects of the oilsands on the fish and people in northern Alberta.

Residents of Fort Chipewyan and Fort MacKay are in the process of adding their signatures to the letter, and a list will be forwarded to Harper.

With files from the CBC's John Archer