Popular discussion of environmental issues has always resembled a boxing match. Too often, news reporters pit two diametrically opposed scientists together, providing a mental image of lab-coated scientists furiously waving reams of graphs at each other. Case in point, last week the Edmonton Journal reported on a new study on contamination in the oil sands region. Dr. William Shotyk, Professor and Bocock Chair in Agriculture and the Environment at the University of Alberta, published a study in the journal Geophysical Research Letters that examined the concentration of lead in peat cores. Peat cores are valuable records of past climate. Peat moss grows in new layers yearly, slowly squishing the plants of years past into the bog. The dust, pollen and contaminants that settle on the peat plants are similarly sealed away in layers of peat, so a core taken carefully from the peat bog can allow you to measure atmospheric concentrations going back many years. In this case, Prof. Shotyk’s group collected peat cores from bogs in the Athabasca Oil Sands Region, and measured the levels of lead going back to 1900, and found that atmospheric lead concentrations peaked around 1980, and has been in decline since. In fact, even bogs closest to the oil sands upgraders show lead concentrations around background. In the Edmonton Journal, Prof. Shotyk was quoted as saying: “Some of these samples we’re analyzing are among the cleanest in the Northern Hemisphere. …. The samples were collected coincidentally right beside the open-pit mines and upgraders.”

The Edmonton Journal turned to another prominent scientist in the ongoing controversy surrounding the environmental effects of oil sands: Dr. David Schindler, Professor Emeritus in the Department of Biological Sciences at the University of Alberta. Dr. Schindler is a an ardent advocate that oil sands development is harming the water resources in the Athabasca River and delta. Previous work by Dr. Schindler’s group has shown increases in a variety of compounds, including lead, in snow close to upgraders. Dr. Schindler cast doubt on Dr. Shotyk’s findings by referring to his own work. And the tableau of paper waving scientists is complete.

What is missing from the ongoing controversy is a nuanced discussion of what the science actually says. A critical question to ask is “would we expect to see higher levels of lead as a result of bitumen mining and upgrading?” As it turns out, lead is not a strong signal of oil sands production. Previous work has shown that concentrations of aluminum, arsenic, chromium, cobalt, iron, molybdenum, silicon, sodium, titanium and vanadium are all more common contaminants from oil sands development. Polycyclic aromatic hydrocarbons, sulfur dioxide and nitrogen dioxide are also of concern. As Prof. Shotyk does point out, lead concentrations have been decreasing since unleaded gasoline was introduced in Canada. The fact that atmospheric lead has been decreasing since this change is interesting in and of itself, interesting, but it doesn’t have a lot to do with oil sands development.

What we do know is that there are higher concentrations of a number of compounds close to the upgraders at the industrial centre of the Athabasca Oil Sands development. What we don’t know yet is how these concentrations are impacting the ecology. It is disingenuous to suggest either that there is no impact, or that the impact is catastrophic. We know that there are impacts – but what we have to decide is whether these impacts are acceptable. This is not a scientific question, it’s a question of values. Unfortunately, we can’t have that conversation while we continue to try to decide environmental questions by amassing two piles of paper on either side of an issue, then saying that the bigger pile, or louder voice, contains the truth. What is happening environmentally around the oil sands is a picture that is slowly becoming clearer; it’s time that how we communicate about these issues becomes clearer as well.

Literature cited:
Shotyk W, Appleby PG, Bicalho B, Davies L, Forese D, Grant-Weaver I, Krachler M, Magnan G, Mullan-Boudreau G, Noernberg T, Pelletier R, Shannon B, van Bellen S, Zaccone C. 2016. Peat bogs in Northern Alberta, Canada reveal decades of declining atmospheric Pb contamination. Geophysical Research Letters.

Kelly E, Schindler D, Hodson PV, Short JW, Radmanovich R, Nielsen CC. 2010. Oil sands development contributes elements toxic at low concentrations to the Athabasca River and its tributaries. Proceedings of the National Academy of Sciences. 107(37): 16178.

Edmonton Journal, September 29 2016. “Research claiming declining levels of atmospheric lead near oilsands in dispute.”