A team led by federal scientist Jane Kirk, also of Environment Canada, will report that snow within 50 kilometres of oilsands operations is contaminated with a long list of "priority pollutants" including a neurotoxin that "bioaccumulates" in food webs.
Kirk's colleague Joanne Parrott will report that melt water from snow collected near oilsand plants is toxic to newly hatched minnows in the lab.
But perhaps the most dramatic findings is that pollutants called polycyclic aromatic hydrocarbons, or PAHs, are building up in lake sediments up to 100 kilometres from the oilsands operations.
"That means the footprint is four times bigger than we found," says David Schindler, an aquatic scientist at the University of Alberta. He and his colleague Erin Kelly made headlines in 2010 when they reported that airborne heavy metals and other pollutants from oilsands operations were contaminating the landscape up to 50 kilometres away.