Oil sands emissions likely underestimated, study finds

Oil sands emissions

Oil sands development in Alberta

Pollution from Alberta's oil sands: The subject has drawn commentary from everyone and their mothers – and most recently rock star Neil Young. But when members of the scientific community weigh in, more people pay attention.

A recent study from the University of Toronto has certainly caught the media's eye.

Researchers Abha Parajulee and Frank Wania say that emissions estimates of potentially toxic chemicals – polycyclic aromatic hydrocarbons (PAHs) – used to approve oil sands development projects are likely too low. In other words, we may have underestimated the impact of oil sands mining on our health and environment.

The study incorporates a wide range of emissions data into multimedia modelling. Taking a comprehensive look at emissions, the study includes not just direct air pollution during the extraction process but also indirect emissions such as evaporation and seepage from tailings ponds, emissions from vehicle traffic, wind erosion and transportation of exposed bitumen.

"Our results highlight the need for improved accounting of PAH emissions from oil sands operations, especially in light of continued expansion of these oeprations," Parajulee and Wania wrote.

The study shows that environmental assessment procedures base their reports on emissions estimates that are likely too low.

"This finding implies that environmental concentrations in exposure-relevant media, such as air, water, and food, estimated using those emissions may also be too low," researchers wrote. "The potential therefore exists that estimation of future risk to humans and wildlife because of surface mining activity in the Athabasca oil sands region has been underestimated."

The researcher's modeling calculated emission levels that are more in line with actual PAH levels measured in samples taken from the Athabasca oil sands region. In fact, the emissions to air levels required to explain the measured concentrations of pollutants would have to be "two to three orders-of-magnitude larger than those reported," the study reads.

Parajulee and Wania's modeling brings Canada's emissions estimates more within range of other major oil-producing nations such as the US and Norway.

Read the full study here.