Hydrocarbon pollution in Alberta waters has increased since mining of the tar sands began in 1967, a new study shows.
The Athabasca River runs through the tar sands region. As it does so, it erodes bitumen from the soil and washes it away. Hydrocarbons have always been present in the Athabasca from natural sources. The study seeks to identify how much of the pollution in the lakes and rivers in the region is natural and how much is from tar sands mining.
The study looked at sediment records in shallow, isolated lakes up to fifty-four miles away from the tar sands mines and found polycyclic aromatic hydrocarbon (PAH) amounts had increased 2.5- 23 times since 1960. Many PAHs are carcinogenic and teratogenic in humans. Hydrocarbons in the most contaminated lake have been exceeding Canadian environmental standards since the 1980s.
The most contaminated lakes were isolated lakes found downwind from the tar sands mines. The hydrocarbons are not coming from erosion by the river, but from air pollution. Air quality in the towns near the tar sands mines is considered acceptable, but tests are not currently being performed for the most dangerous PAHs.