More than 170 doctors are calling on the federal government to withhold approval for a huge oilsands project in Alberta, just south of the Northwest Territories border, and requesting that more research be done on its potential impact on human health.

Earlier this month, the Canadian Association of Physicians for the Environment wrote a letter to Prime Minister Justin Trudeau and Environment Minister Jonathan Wilkinson, expressing concerns about the project's potential health impacts.

Vancouver-based Teck Resources Ltd. is aiming to build the Frontier mine about 100 kilometres north of Fort McMurray.

The fate of the proposed $20.6-billion Teck Frontier oilsands mine is set to be decided by the federal government next week. It is estimated to take up 29,217 hectares of land near Wood Buffalo National Park.

Over 170 doctors sign on

Yellowknife doctor Courtney Howard is president of the Canadian Association of Physicians for the Environment, and is one of over 170 doctors who signed the letter.

Dr. Howard said there has been local demand for more research on the health impacts of oilsands for years.

"The local communities downstream from the mine have been asking for a comprehensive cumulative assessment of the health impacts of the oilsands for over a decade," she said.

'Grave consequences for the future'

Dr. John O'Connor, a physician in Fort McMurray who signed the letter, is one of the voices who has been asking for further research into the environmental health impacts for over a decade.

"I would still like to see an independent health study, a comprehensive health study," he said. "Unfortunately with all the calls over the years…these recommendations have been ignored."

In 2006, Dr. O'Connor raised concerns about rates of cancers downstream from major petroleum refineries in Fort Chipewyan, Alta.

Dr John O’Connor, a physician in Fort McMurray, has been asking for comprehensive research into the health impacts of the oilsands for over a decade. (Submitted by Dr. John O'Connor )

At the time, Health Canada physicians filed complaints against O'Connor with the College of Physicians and Surgeons of Alberta, accusing him of causing undue alarm.

An investigation done by the college found that O'Connor "made a number of inaccurate or untruthful claims with respect to the number of patients with confirmed cancers and the ages of patients dying from cancer."

FROM 2009 | Doctor's Fort Chip cancer numbers disputed

But in 2009, O'Connor was cleared of causing undue alarm, and a study the same year from the Alberta Cancer Board found that cancer rates were indeed higher than expected in Fort Chipewyan, by 30 per cent.

Subsequent studies have challenged those findings.

In 2010, the Royal Society of Canada concluded that there was no credible evidence of "environmental contaminant exposures from oilsands reaching Fort Chipewyan at levels expected to cause elevated human cancer rates."

And in 2014, a follow-up study from the Alberta government found the community didn't have higher overall rates of cancer.

Comprehensive study needed

Dr. O'Connor said he said he would like to see an independent and comprehensive health study of the project, regardless of whether it gets approved.

"The Teck project, if it does go ahead, will have grave consequences for the future — especially in the North," he said.

Those who signed the letter agree the assessment that was done of the project was not comprehensive in its explanation of what the health effects will be on future generations, and a comprehensive study is still needed.

Those who signed on also assert that the link between climate change and health is conclusive.

"Climate change is a health emergency and we need to treat it like a health emergency," said Dr. Howard.

The project is expected to generate 4.1 million tonnes of carbon dioxide annually, and would operate for 41 years if approved.

The Frontier oilsands mine is a proposed 292-square-kilometre open-pit operation, located between Fort McMurray and Fort Chipewyan, pictured above, in northeast Alberta. (Jeff McIntosh/CP)

Health assessment of project

In July, a joint federal-provincial review panel gave conditional approval to the Frontier mine, finding it was in the national interest.

The review estimates that 7,000 jobs will be created in building the mine, and 2,500 workers will be needed to operate it.

The report completed a human health risk assessment of the project, and found that "the project is not likely to result in an increase in cancer risk."

"Although we find that there will be significant adverse project and cumulative effects on certain environmental components and Indigenous communities ... we consider these effects to be justified."