Federal Environment Minister Jim Prentice says scientists have consistently told him toxic pollutants in the Athabasca River are not from the oilsands industry. (Canadian Press) Environment Minister Jim Prentice says federal scientists have always told him that any contaminants such as lead or mercury in the Athabasca River are naturally occurring, not from the oilsands industry.

"That has consistently been what I've been told as minister by the federal scientists," he said from Saint-Jean-sur-Richelieu, Que., where he was taking French lessons.

But Prentice added that he's aware of scientific controversy on the issue.

"There are scientists who appear to disagree with this assertion," he said.

On Monday, University of Alberta ecologist David Schindler published a paper that he said proved that heavy metals, including lead and mercury, are being released from oilsands facilities into the air and water of northern Alberta.

Schindler said the study was specifically designed to determine the source of the contaminants. Several heavy metals were found to be above levels considered hazardous to fish in some areas, he said.

Schindler said the study's conclusions justify an increased federal presence in monitoring and enforcement of the oilsands.

But Ottawa has already increased its presence in the oilsands, Prentice said.

He said federal money has helped increase groundwater monitoring in the region from 25 to 100 sites.

Toxin fingerprinting technology

He also said Environment Canada has paid $1.6 million for crucial technology now at the University of Saskatchewan in Saskatoon that will enable scientists to "fingerprint" contaminant chemicals found in the air and water. They'll be able to say definitively whether they came from naturally occurring bitumen deposits or from industrial emissions, he said.

Because air and water pollution create interprovincial impacts, they come under federal jurisdiction.

But before Ottawa takes any action on contaminants, Prentice said, it's vital to understand their sources.

"I have been pushing and challenging what I have been told on the science," he said. "We have to be certain there are no pollutants in the Athabasca River."

Federal Liberal environment critic David McGuinty said that isn't good enough.

"The federal government has to exercise its exclusive constitutional responsibility and enforce its existing environmental standards," he said in Baddeck, N.S., during a Liberal caucus retreat.

"That means Fisheries Act prosecutions if required, that means exercising the powers they have at their fingertips. Minister Prentice has got to stop bobbing and weaving now and he's got to do his job."

'Insignificant levels'

Alberta Environment Minister Rob Renner says provincial scientists are telling him levels of toxins detected in the Athabasca River are not a concern. (CBC)Meanwhile, Alberta Environment Minister Rob Renner repeated government assertions that oilsands-associated contaminants are found in higher concentrations near industrial facilities because that's where the bitumen is most concentrated.

"Common sense says that if you dig a hole in the ground, in the immediate vicinity of that hole you may have some disturbances," Renner said.

"Everything that you do in this world has some impact. What we have to do is determine what are the levels at which we need to have some concern, and my scientists are telling me that the amount of compounds that can be detected in the Athabasca River at this point in time are not a concern and are at insignificant levels."

Renner dismissed Schindler's conclusions as differences in the interpretation of data and said Alberta is in the middle of a three-year study on contaminant loading in the area.

However, New Democrat MLA Rachel Notley wondered why the provincial Conservatives have long maintained there are no contaminants from industry in the Athabasca when an Alberta Environment spokeswoman acknowledged Monday that that's where at least some of the heavy metals probably originate.

"What we have appears to be a contradiction, where we have officials of the Ministry of Environment acknowledging that they knew there was contamination contrasted with statements by the premier and the minister in the legislature insisting that there is not," Notley said.

"On the surface, it doesn't look good for the level of trust of any statement that come from this government with respect to environmental matters."