Research conducted for the Athabasca Chipewyan First Nation in northern Alberta has cast doubt on a government study about the town's water quality and its connection to cancer rates.

The study, by Kevin Timoney, was done to determine whether oilsands pollution is making people sick through the water supply.

Timoney's research, presented to the community of 1,200 on Wednesday evening, found that elevated levels of arsenic and mercury in the water and wildlife are cause for health concerns.

"We looked at things such as arsenic, mercury, methylmercury, a variety of heavy metals, polycyclic aromatic hydrocarbons, dioxins, furans, naphthenic acids, et cetera," he told CBC News Thursday in an interview.

"We found that there is reason to be concerned that levels of arsenic, mercury and polycyclic aromatic hydrocarbons are higher than would be considered safe."

Those levels are particularly higher in local fish, according to his report. Timoney looked at data from 1970 to the present, focusing on the Peace River, Athabasca River and the Peace-Athabasca Delta near Fort Chipewyan.

Levels of polycyclic aromatic hydrocarbons rose between 2001 and 2005 in sediment in the Athabasca Delta, the report says, with current levels considered unsafe to aquatic life.

Timoney's conclusions are in stark contrast to a government-funded study this year on cancer rates that found no elevated disease rates in connection with the Athabasca River.

Timoney said there seems to be a reluctance on the part of governments and industry "to admit there is any cause for concern even though the data suggests there is a cause for concern.

"I can't answer for the government and industry as to why they would always downplay the risk," he said.

"Certainly the numbers indicate to any objective scientist that there is a cause for concern."

He urged the people of Fort Chipewyan to push for yet another independent study of the water and wildlife.

He said the contaminants were not only found in fish, but also in waterfowl, muskrat, beavers, and moose — all of which are traditional foods that the community relies on.

Resident Ray Ladouceur, who has fished on Lake Athabasca for about 50 years, said he has pulled deformed fish from his nets. He said he believes the fish are sick because of the chemicals from the oilsands in Fort McMurray.

"I've seen many changes in this, the water. There's all kinds of stuff coming down," Ladaceur said.

"You can see it right in the water, there's kind of a scum, I guess, flowing down the river."

As for the town's water supply, Timoney said the water treatment system is working well and the water is safe to drink.

Fort Chipewyan is located downstream from Fort McMurray, the heart of the province's oilsands development.