Water pollution levels around the Athabasca River and its tributaries have risen because of emissions from the oil sands, a research paper released Monday says , contradicting a view in the energy industry and the Alberta government that the massive mining of bitumen hasn't contaminated waterways.
The finding, published in the peer-reviewed Proceedings of the National Academy of Sciences, is likely to add to the environmental headaches of the oil sands industry, which has been in a negative spotlight for its large-scale emissions of greenhouse gases.
The research, conducted mainly by scientists at the University of Alberta, found that concentrations of polycyclic aromatic compounds, or PACs, were far higher at sites near and immediately downstream from mining operations and upgraders than they were upriver from oil sands developments. The paper also estimated airborne emissions of PACs from the industry's activities as amounting to a major oil spill each year if they were in a single place.
PAC are a component of oil and a major concern to public health authorities and environmentalists because they can be toxic to fish embryos, even at vanishingly small concentrations, and are linked to cancer.
At sites in the oil sands area where nearby land has not been disturbed, PAC levels in rivers are similar to what is found in remote Canadian Arctic waterways, but in areas most affected by extraction activity, they rise by 10 to nearly 50-fold, reaching amounts within the range of harm to aquatic life.
“There is potential harm to fish in the river,” said David Schindler, a biologist at the University of Alberta and one of the scientists who conducted the study. He said that the finding indicates “a clear violation” of the federal Fisheries Act, which makes it illegal to add substances harmful to fish into waterways.
But the Alberta government disputed the conclusions of the research paper.
The province has contended that PAC levels found in the water are due to natural seepage from nearby soil that contains high levels of the compounds due to the presence of bitumen.
Preston McEachern, a spokesman on the oil sands for Alberta's Ministry of Environment, said bitumen extraction is done in the areas with the highest amounts of petrochemicals in the ground, which in turn explains high levels detected in nearby rivers. He said the concentrations detected, in the parts per trillion, weren't high enough to be a concern.
