WWF says harmful dispersant should not be used for oil spill “cleanup”

At WWF-Canada, we oppose the approval of Corexit 9500A as an oil spill-treating agent due to high levels of toxicity and its overall ineffectiveness at shielding shorelines, seabirds and marine mammals from oil spill damage.
WWF-Canada made this position clear in a letter to Environment Minister Leona Aglukkaq, in response to Environment Canada’s request for submissions on whether to add new products, such as the dispersant Corexit 9500A, to an approved list for use in oil spill cleanup operations.

The application of chemical dispersants is a controversial means to respond to an oil spill and for good reason. The idea that dispersants can protect seabirds and marine mammals remains questionable. Even a thoroughly effective chemical dispersal of oil, if it could be achieved for a limited tactical application, would not protect seabirds and marine mammals from encountering the dispersed oil when they dive into the water column to feed. The more likely result is that a dispersant application will drive some oil into the water column, while much of it remains on the surface. Seabirds and marine mammals will then encounter oil and chemically-dispersed oil on the surface and underwater.
Dispersants are products which are meant to break up slicks of oil into small droplets, making them easier to disperse throughout large volumes of water and speeding up the rate at which they biodegrade. Though some chemicals have been known to be effective in this manner, others have shown vast discrepancies in their success between lab tests and real-world applications.
Corexit 9500A does not have a reliable enough track record in the field to be listed as a spill-treating agent. In some cases—such as the Deepwater Horizon blowout—it was shown to disperse less than 10 per cent of the oil from the water’s surface, still leaving much of the oil to come into contact with shorelines, seabirds and mammals.
A further concern of adding this product to the list of spill-treating agents is that it creates the false impression that there is a simple fix when an environmentally ruinous blowout occurs. Large oil companies often seek regulatory approval for their activities on the basis that they have a cleanup plan; that they can deploy dispersants to ‘treat’ such spills on a grand scale. However, evidence suggests that applying dispersants, such as Corexit9500A, to oil spills is at best ineffective and at worst an exacerbating factor; thus creating a scenario where the cure is worse than the disease.
This false impression of a quick fix for oil spills is of great concern to WWF-Canada, as melting sea ice opens up the North to increased (economic) development, including oil and gas extraction in both the western Arctic in the Beaufort Sea, and the eastern Arctic in Baffin Bay. For the past several years, WWF-Canada has, along with Ecojustice, made several submissions to the National Energy Board demanding that the board not grant any exceptions to strict safety regulations of offshore drilling activities.
The logical conclusion? There is only one way to effectively treat an oil spill: prevent it from happening in the first place.