Dispersant from Deepwater Horizon Spill Found to Persist in the Environment

Posted In Gulf Oil Catastrophe, News
Jul
16

dispersant-oil-spill
Plane Drops Dispersants on Oil Spill. Captions and Photo source: ©© NWF

By Woods Hole Oceanographic Institution;

The 2010 Deepwater Horizon (DWH) spill in the Gulf of Mexico was the largest accidental release of oil into the ocean, with approximately 210 million gallons gushing from the blown out well. In an attempt to prevent vast quantities of oil from fouling beaches and marshes, BP applied 1.84 million gallons of chemical dispersant to oil to oil released in the subsurface and to oil slicks at the sea surface. The dispersant was thought to rapidly degrade in the environment.

A new study by scientists at Haverford College and Woods Hole Oceanographic Institution (WHOI) has found that the dispersant compound DOSS, which decreases the size of oil droplets and hampers the formation of large oil slicks, remains associated with oil and can persist in the environment for up to four years.

The study was recently published in Environmental Science & Technology Letters.

The study examined samples collected from deep-sea corals and surrounding sediments collected in Dec. 2010 as well as oil-soaked sand patties found on coastal beaches since July 2010 to the present.

“We found DOSS persisted in variable quantities in deep-sea coral communities 6 months after the spill and on Gulf of Mexico beaches 26−45 months after the spill,” said lead author Helen White, an assistant professor of chemistry with Haverford College. “These results indicate that the dispersant, which was thought to undergo rapid degradation in the water column, remains associated with oil in the environment and can persist for around 4 years.”

Finding dispersant in the deep-sea samples they analyzed did not come as a surprise to the researchers. Earlier work by co-author Elizabeth Kujawinski and her colleagues found DOSS was slow to degrade in the deep ocean. “The deep sea is cold and dark and the degradation of dispersant components happens much more slowly under these conditions,” said Kujawinski, an associate scientist at WHOI. “The interesting thing is that the sand patties we’re finding on beaches four years after the spill have DOSS in them. That was somewhat unexpected.”

White and her colleague Chris Reddy at WHOI have been monitoring the beaches for oiled samples since the time of the spill. This fieldwork is part of an effort to gain as much understanding about the geographical and temporal distribution of the sand patties.


For this study, which was funded by the Gulf of Mexico Research Initiative (GOMRI), White and her team at Haverford developed a method to isolate the DOSS from the solid sand patties. Prior to this study, dispersant had only been analyzed in aqueous samples. White then sent the isolated compounds to Kujawinski’s lab at WHOI, where researchers used sophisticated instruments to quantify the DOSS in samples collected from environments known to contain oil persisting from the DWH oil spill.

“The amounts we detected are quite small, but we’re finding this compound in locations where we expected the dispersants to disappear, either by dissolving in water or by being degraded by bacteria,” said Kujawinski.

What does the presence of DOSS in deep-sea sediments and corals and in sand patties on Gulf beaches mean for marine life or for the people who frequent the beaches? The scientists say the honest answer is they don’t really know.

“It’s hard to say because we don’t know how toxic it might be. The EPA has determined what concentrations of DOSS may be harmful to marine life in the water, but the toxicity of DOSS in solid (non-aqueous) forms like sediments or sand patties is not known,” said White. “We know that if you measure ‘x’ amount of this compound in ‘y’ amount of water, that’s toxic. But you can’t compare those numbers to what we’ve found in the sand patties because we’re looking at this compound in a mixture of sand and oil.”

Until more is known about the toxicity of oil and dispersant mixtures, some Gulf beaches have signs to warn people not to touch the sand patties.

The researchers are eager for their findings to be known by other scientists studying the Deepwater Horizon spill. “We want to get this information out there because there are other scientists who are studying similar samples,” said White. “When they ask questions about which microbes are living in the samples or how the oil is changing over time, it’s really important to consider that the samples also contain dispersants.”

The researchers hope to focus future research on gaining a better understanding of why dispersant compounds are able to persist in the environment for so long. In particular, they are interested in learning how they escape degradation in coastal environments where temperatures are higher for a significant part of the year and there is more exposure to sunlight.

“The dispersant was not expected to persist for so long,” Kujawinski said.

“Now that we know that it can be found up to 4 years after the spill, there is even more need to understand it and any impacts it may have on the environment.”

Original Article And Learn More, Woods Hole Oceanographic Institution

First Study of Dispersants in Gulf Spill Suggests a Prolonged Deepwater Fate, Woods Hole Oceanographic Institution (01-27-2011)
To combat last year’s Deepwater Horizon oil spill, nearly 800,000 gallons of chemical dispersant were injected directly into the oil and gas flow coming out of the wellhead. Scientists begin to assess and to raise questions about what impact the deep-water residue of oil and dispersant, might have had on environment and marine life in the Gulf.

Gulf Oil Spill: Oil-Dispersing Chemicals Had Little Effect On Oil Surfacing, Science Daily (12-04-2012)
A new study is the first to examine the effects of the use of unprecedented quantities of dispersants, over such a prolonged period of time in the deep ocean.

Link Between Oil Spill Exposure and Hematologic, Hepatic Toxicity, Science Daily (09-17-2013)
A new study reports that workers exposed to crude oil and dispersants used during the Gulf oil spill cleanup display significantly altered blood profiles, liver enzymes, and somatic symptoms compared to an unexposed control group…

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Resources

Federal

  • Deep Water Horizon Response is the official site of the incident in conjunction with BP, DOI, NPS, USGS, CDC, USFWS, NOAA and other branches of the US government (collectively called Unified Command). Information, including the latest news, photos, area plans, and volunteer information.
  • NOAA is a government program that uses science and research to protect life, property and natural resources. This NOAA site provides maps of the spill and related statistics, including a trajectory forecast map for the oil spill.
  • The Environmental Protection Agency provides data on Air, Land, and Water pollutants including sampling maps and contaminant levels.

Louisiana

  • Volunteer Louisiana is the official site for the State of Louisiana to get involved in the spill response.
  • The Louisiana Department of Wildlife and Fisheries provides maps of closures to fishing areas in LA.
  • The Louisiana Emergency Office has made Google Earth files of the spill available to the public here http://gohsep.la.gov/oilspill.aspx and also has current information on general closures of waterways, photos, and reports.
  • The Audubon Nature Institute site provides a number for citizens to call if turtles, manatees, dolphins, or other animals are in distress
  • The Oiled Wildlife Care Network is a CA based non-profit is advising folks in the Gulf of Mexico on best practices and provide resources on how people can help.
  • The Coalition to Restore Coastal Louisiana is a non-profit organization who strive to protect and restore coastal Louisiana. Volunteers are needed for numerous actions including: monitoring, oiled wildlife recovery, boat driving, or simple monetary donations.
  • The Greater New Orleans Foundation is a philanthropic organization in Louisiana and the surrounding region that joins with other non-profit, foundations and community and government officials to address the needs of the community. The Foundation has opened the Gulf Coast Oil Spill Fund.
  • The Louisiana Bucket Brigade is an environmental health and justice organization working with communities near oil refineries and chemical plants. They aid residents in these regions to reduce pollution and protect public health. The Brigade has formed an incident map where you can report observed signs of oil.

Alabama

  • The Alabama Coastal Foundation is an education based organization whose mission is to project the quality of Alabama’s coastal resources. They are currently training volunteers to help directly with the spill response.
  • The site by the Alabama Governor’s Office of Faith-Based and Community Initiatives gives basic phone numbers.
  • The Mobile Bay National Estuary Program is an organization funded by the EPA fighting the environmental challenged facing Mobile Bay. This site gives e-mail addresses and phone numbers to help and provides basic information.
  • The Mobile Bay Keeper is a group of citizens who are interested in preserving the Mobile Bay watershed as well as protecting the health of the individuals and environment in the Bay. Check out the latest information about the spill and learn how to become a member and donate to the cause.

Mississippi

Florida

  • The Florida Department of Environmental Protection is the lead agency in FL and this website provides the most thorough information in the state.
  • Volunteer Florida, the website of the Governor’s Commission on Volunteerism and Community Service and the State Emergency Response Team, lists volunteer opportunities by county.
  • The Escambia County site provides summary points of actions taken by BP and FL with a focus on the County.
  • The Pinellas County site is a concise list of related local websites and numbers for information.
  • The Gulf County site has current news on the spill as it relates to the county
  • Volunteer directly with the largest wild bird hospital in the United States, the Suncoast Seabird Sanctuary.

Organizations and other networks

  • American Birding Association
  • Audubon is a global leader in protecting birds and other wildlife and their habitats. They are partnering with other organizations.
  • The Sierra Club is a grassroots environmental organization that works to protect communities, wild places, and the planet. Updates on the oil spill, as well as volunteer and donation information.
  • The Nature Conservancy is a conservation organization with a mission to preserve and protect ecologically significant lands and waters for nature and people. Learn more about the oil spill and how to help out at http://www.nature.org/wherewework/northamerica/states/alabama/features/oilspill.html and check out their blog.
  • Sea Grant is nationwide network (administered through NOAA) of 32 university-based programs that work with coastal communities on environmental stewardship and the responsible use of our coasts. The Gulf of Mexico Sea Grant Programs provides resources to educators with research that may be impacted by the spill.
  • The National Wildlife Federation is America’s largest conservation organization whose mission is to protect and restore wildlife habitat, confront global warming and connect with nature. Get the latest information on the oil spill crisis and how to help.
  • The mission of Tri-State Bird Rescue and Research is to provide rehabilitation of injured, orphaned, and oiled native wild birds to return to their natural environment. Donate to their research.
  • Green Peace is an international organization that strives to save the planet from environmental threats such as global warming, destruction of forests and deterioration of the oceans. Follow their blog and learn how to take action.
  • Global Green USA is an international environmental non-profit organization with an office in New Orleans that strives to fight global climate change, eliminate weapons of mass destruction and create clean, safe drinking water for all. Follow their blog and get involved.
  • Matter of Trust is a non-profit organization focused on materializing sustainable systems by mimicking Mother Nature as well as concentrating on manmade surplus, natural surplus and eco-educational programs. Learn very simple ways to help the oil spill crisis.
  • The official Facebook page of Unified Command.
  • BP Gulf of Mexico response.