Scientists study effects of oil spill dispersants on Arctic wildlife
Scientists are taking a close look at the effects of chemical dispersants on seabirds. These are chemicals used in marine oil spill response to provide an environmental benefit to limit sea surface contamination and to reduce contamination of coastal habitats.
However, scientists have incomplete knowledge of the physical effects on seabirds of chemical dispersants and oil treated by the dispersants. Less is known about the effects of dispersants on wildlife in Arctic waters, where residents of coastal communities depend on food gathered from northern seas.
A group of scientists is focusing on related public health and food safety as a sector of a five-prong research program. They are seeking public input, especially from residents of Arctic and Alaska coastal communities.
Studies and oil spill events have shown that oil contamination on plumage disrupts the benefits of the natural waterproofing the birds put on themselves to protect their bodies from the environment. Scientists have long known that exposure to oil in spills causes loss of buoyancy, temperature control and reduced ability to fly or dive that can cause birds to die. Preliminary findings released by a study of common murres [Uria aalge] through the Karen C. Drayer Wildlife Health Center at University of California show that effects of exposure to dispersants and chemically dispersed oil within the first 24 hours are similar to impacts of exposure to oil.
The study concludes that “exposure to high concentrations of dispersant impairs waterproofing to such an extent that affected animals may drown rapidly,” according to the report. Current methods for cleaning seabirds are equally effective for birds contaminated by dispersant and dispersed oil as for birds contaminated by crude oil. Response to the largest marine oil spill in history, caused by an explosion on the Deepwater Horizon oil rig in the Gulf of Mexico in April 2010, relied heavily on chemical dispersants. The spill impacted a wide variety of species populations: oysters, fish, corals, sea birds and whales.
The use of dispersants in the Gulf of Mexico generated thinking about the use of chemical dispersants as an option should a spill of similar size occur in Arctic waters. This issue and one of the outcomes of an oil spill drill for senior federal leadership pointed to the need for a state-of-science evaluation considering knowns and unknowns about use of dispersant in the Arctic. To meet this need, University of New Hampshire’s Coastal Response Research Center, CRRC for short, coordinated a discussion among scientists with DDO expertise to determine what was known regarding use of DDO in Arctic waters. DDO is a short way of referring to dispersants and dispersed oil. In the CRRC program, separate panels of scientists met to focus on the following topics concerning dispersants and dispersed oil: Efficacy and efficiency; Physical transport and behavior; Degradation and fate; Toxicity to the environment and sublethal impacts; Public health and food safety.
Scientists made a list of reference and research documents on DDO for each topic, which were released between June 2008 and Dec. 31, 2015. For each topic the scientists made a list of knowns about the state-of-science concerning DDO and Arctic waters. They also made a list of uncertainties about DDO as it applies to Arctic waters. The CRRC is currently collecting written public input on health and food safety with a deadline of July 13.
The Nome Port Commission discussed dispersants with USCG LCDR Jeff Altendorf at their most recent meeting. CRRC is working under the aegis of Arctic Domain Awareness Center through the Dept. of Homeland Security, Altendorf explained. The Captain of The Port has the authority to authorize the use of dispersants. A plan has to be followed, Altendorf said. The CRRC project is a huge effort that looks at many things. He suggested people look at the issue through the lens of when the USCG would use dispersants offshore. The current study is a study of studies to see what information is available now, with the hope that down the line a nonscientific regulatory body can more easily make a decision on the use of dispersants on a case by case basis, Altendorf explained.
Commissioner Gay Sheffield, a marine biologist with UAF Sea Grant, stressed the complexity of looking at the effects of dispersants on seabirds, which are abundant in the area and used as a food source. Seabirds preen constantly and keep themselves waterproof, but when they contact dispersants which act as detergents, they become immediately stressed and lose their waterproofing. Even if a bird recovers, there are questions on whether it would be safe to eat it. Dispersants breaking oil into little drops does not make it go away and may make it more available to damage fish, birds, other marine resources, by going through the walls of cells, for example.
Commissioner Charles Lean, fish biologist, shared Sheffield’s concerns and worried about oil and dispersants going to the bottom into crab and clam beds.
“Is oil or dispersant more harmful?” Lean mused. “You have to balance the benefits and effects of dispersants on having massive amounts of oil floating around among wildlife.”
“We don’t know how much research is out there on Arctic waters. That is what the project is to find out,” Altendorf said. He advised the Commission that there would be opportunities to offer comment throughout the process.
“At the very least, we should write a letter saying we have great interest and are very concerned,” Lean opined.
“This issue is not going to go away,” Altendorf said. “It is going to be part of oil spill response in Alaska.”