An unpublished federal report on environmental threats from oil and bitumen pipelines says little is known about the potential toxic effects of oilsands products in oceans, lakes or rivers.
"In particular, research on the toxicology of bitumen is lacking," says the draft report, commissioned in response to concerns raised at the Northern Gateway pipeline hearings.
'Research on the biological effects of oilsands-related products on aquatic organisms is lacking.'- Draft federal government report from 2013
The document comes as Canada debates pipeline proposals for moving large amounts of diluted bitumen from Alberta's oilsands to refineries and ports on both coasts and into the United States. It was obtained by Greenpeace under freedom-of-information legislation.
Although it has been through several versions, the 2013 report has never been released.
More complete report expected
"A more complete, peer-reviewed report was produced by (Fisheries and Oceans), and will be published in the coming months," wrote department spokesman David Walters in an email.
Raw bitumen and diluted bitumen are displayed in jars during a news conference in Vancouver in 2012. A draft federal government report says the effects of a spill of bitumen are largely unknown. (Darryl Dyck/Canadian Press)
All drafts of the report warn that the behaviour and effects of bitumen remain largely unknown.
"Research on the biological effects of oilsands-related products on aquatic organisms is lacking," it says.
An early draft lays out 10 specific "knowledge gaps" about bitumen and the various substances used to dilute it when it's pumped through pipelines.
"Very little information is available on the physical and chemical characteristics of oilsands-related products following a spill into water," it says.
"A better understanding of the fate and behaviour of these products is critical for assessing the potential risk to aquatic organisms."
More research is needed on what would happens to heavy metals in bitumen in the case of a spill. There is a "lack of information" on how condensate — a lighter hydrocarbon used to dilute bitumen for pumping — would behave in water.
The understanding of how chemicals in bitumen would interact with fish should be improved, the report says. Specific research on possible oil impacts on the Pacific, Arctic and Great Lakes is needed.
The impact of sunlight, which can make some chemicals in bitumen vastly more harmful, is also unknown, says the report. The combined effect of bitumen and dispersants — chemical agents used to break up oil spilled in water — hasn't been studied.
As well, little is known about the potential impacts of a spill in the Arctic.
The early draft of the report examines research on Orimulsion, a Venezuelan product about two-thirds bitumen and one-third water.
Studies say Orimulsion tends to sink in fresh water, but remain suspended throughout the water column in salt water. It is also "highly toxic to fish" — 300 times more toxic to embryos than heavy fuel oil.
The 61-page draft includes 14 pages of references to peer-reviewed academic studies as well as government and industry publications. They date from 1976 to 2013 and include articles from a wide variety of scientific journals.
New research underway
Walters said new research is already underway.
"The information collected during this exercise has already resulted in (the department) providing Canadian universities with funding for five projects related to the effects on fish and shellfish," he said.
The government also recently released research that found bitumen tends to float on sea water, but responds poorly to dispersants and shows "significant" differences from conventional crude.
Prominent ecologist David Schindler, whose work is cited in the review, said the real state of knowledge about the potential effects of a bitumen spill is even sketchier than the review suggests.
The report adopts a piecemeal, substance-by-substance approach instead of considering the combined effect of all chemicals, he said. It also doesn't ask what happens if a spill gets under river ice, which has already happened on Alberta's Athabasca River.
"The recommended list of new activities will not solve these shortcomings," Schindler said in an email. "They are simply recommending more of the same deficient tests, fine for initial screening, not for protecting ecosystems."
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