Environmental impact of the Deepwater Horizon oil spill
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Deepwater Horizon oil spill
The 2010 Deepwater Horizon oil spill in the Gulf of Mexico has been described as the worst environmental disaster in the United States, releasing about 4.9 million barrels (210 million US gal; 780,000 m3) of crude oil making it the largest accidental marine oil spill. Both the spill and the cleanup efforts had effects on the environment.
The oil spill was called the "worst environmental disaster the US has faced" by White House energy adviser Carol Browner. The spill was by far the largest in US history, almost 20 times greater than the usual estimate of the Exxon Valdez oil spill. Factors such as petroleum toxicity, oxygen depletion and the use of Corexit are expected to be the main causes of damage.
Impact to marine species
Most of the impact was on the marine species. Eight U.S. national parks were threatened and more than 400 species that live in the Gulf islands and marshlands are at risk, including the endangered Kemp's Ridley turtle, the Green Turtle, the Loggerhead Turtle, the Hawksbill Turtle, and the Leatherback Turtle. In the national refuges most at risk, about 34,000 birds were counted, including gulls, pelicans, roseate spoonbills, egrets, terns, and blue herons. A comprehensive 2009 inventory of offshore Gulf species counted 15,700. The area of the spill includes 8,332 species, including more than 1,200 fish, 200 birds, 1,400 molluscs, 1,500 crustaceans, 4 sea turtles, and 29 marine mammals. In a 2011 paper in the journal BioScience, researchers from the University of New Hampshire reported that the spill threatened 39 marine species in addition to the 14 currently under federal protection. Threatened species, the report found, ranged from 'whale sharks to seagrass".
Harry Roberts, a professor of Coastal Studies at Louisiana State University, has stated that 4 million barrels (640,000 m3) of oil would be enough to "wipe out marine life deep at sea near the leak and elsewhere in the Gulf" as well as "along hundreds of miles of coastline." Mak Saito, an Associate Scientist at Woods Hole Oceanographic Institution indicated that such an amount of oil "may alter the chemistry of the sea, with unforeseeable results." Samantha Joye of the University of Georgia indicated that the oil could harm fish directly, and microbes used to consume the oil would reduce oxygen levels in the water. The ecosystem, she said, could require years or decades to recover, as with previous spills. Damage to the ocean floor would endanger the Louisiana pancake batfish in particular, whose range is entirely contained within the area affected by the spill.
The actual number of mammal deaths due to the spill may be as much as 50 times higher than the number of recovered carcasses, according to a study published in the Journal Conservation Letters. "The Deepwater oil spill was the largest in US history, however, the recorded impact on wildlife was relatively low, leading to suggestions that the environmental damage of the disaster was actually modest. This is because reports have implied that the number of carcasses recovered... equals the number of animals killed by the spill" stated Rob Williams from University of British Columbia.
On 22 October 2010, it was reported that miles-long strings of weathered oil had been sighted moving toward marshes on the Mississippi River delta. Hundreds of thousands of migrating ducks and geese spend the winter in this delta. Two years after the Deepwater explosion, migratory birds were found to have carried chemicals from the spill to Minnesota. Preliminary evidence showed the vast majority of the small sample of Pelican eggs tested contained "petroleum compounds and Corexit". As of 2 November 2010, 6,814 dead animals had been collected, including 6,104 birds, 609 sea turtles, 100 dolphins and other mammals, and 1 other reptile. According to the U.S. Fish and Wildlife Service, cause of death had not been determined as of late June. According to NOAA, since 1 January 2011, 67 dead dolphins had been found in the area affected by the spill, with 35 of them premature or newborn calves.
A NOAA study in Spring 2012, along with two other studies reported at the same time, suggest that the long-term environmental effects of the spill may have been "far more profound than previously thought". The joint study by NOAA and BP found "many of the 32 dolphins studied were underweight, anemic and suffering from lung and liver disease, while nearly half had low levels of a hormone that helps the mammals deal with stress as well as regulating their metabolism and immune systems". Researchers found that some types of spiders and other insects were far less numerous than before the spill.
During a January 2013 flyover, former NASA physicist Bonny Schumaker noted a "dearth of marine life" in a radius 30 to 50 miles around the Macondo well. "Since the fall of 2011, now about 14 months, I see no turtles, few if any dolphins, few if any rays ... few sharks, few bait balls, all of the things we used to see," she commented. This may mean that the wildlife left the area in search of food. "I guess the Gulf of Mexico in these parts is a stinky, dead desert for its previous visitors," Schumaker told NBC news.
Three years after the oil spill, the residual effects were still apparent, with tar balls still found on the Mississippi coast, as well as an oil sheen along a coastal marsh, and erosion on an island in Barataria Bay sped up by the death of mangrove trees and marsh grass.
In November 2010, federally funded scientists found damage to deep sea coral several miles from the well. Expedition leader and biologist with Penn State University Charles Fisher said there was "an abundance of circumstantial data" suggesting coral damage is related to the spill. This discovery indicated that the spill's ecological consequences may be greater than was previously officially claimed. "The visual data for recent and ongoing death are crystal clear and consistent over at least 30 colonies; the site is close to the Deepwater Horizon; the research site is at the right depth and direction to have been impacted by a deep-water plume, based on NOAA models and empirical data; and the impact was detected only a few months after the spill was contained."
In March 2012, definitive link was found between the death of a Gulf coral community the size of half a football field and the spill. The scientists wrote: "The presence of recently damaged and deceased corals beneath the path of a previously documented plume emanating from the Macondo well provides compelling evidence that the oil impacted deep-water ecosystems."
In February 2011, the first birthing season for dolphins since the spill, the director of the Institute for Marine Mammal Studies in Gulfport reported that dead baby dolphins were washing up along the Mississippi and Alabama shorelines at about 10 times the normal number for the first two months of the year. "For some reason, they have started aborting or they were dead before they were born; the average is one or two a month. This year we have 17 and February is not even over yet." It is not yet certain if the deaths are related to the spill.
From mid-January to late March 2011, scientists counted almost 200 dead dolphins in the Gulf, with another 90 in 2010. After investigating the deaths, NOAA put a gag order on the results, saying that the research is part of a criminal investigation of the spill. Numerous independent scientists said they have been "personally rebuked by federal officials for speaking out of turn to the media about efforts to determine the cause" of the deaths.
In April 2011, one year from the onset of the spill, scientists confirmed that they had discovered oil on dead dolphins found along the Gulf Coast. Fifteen of the 406 dolphins that had washed ashore in the last 14 months had oil on their bodies; the oil found on eight of them was linked to the spill. A NOAA spokesperson said it was "significant that even a year after the oil spill we are finding oil on the dolphins, the latest just two weeks ago." A NOAA study in the summer of 2011 showed dolphins that came in contact with the petroleum were "seriously ill" with drastically low weight, low blood sugar and for some, cancer of the liver and lungs.
In December 2013, the journal Environmental Science & Technology published a study finding that of 32 dolphins briefly captured from 24-km stretch near southeastern Louisiana, half were seriously ill or dying from liver disease, pneumonia, loss of teeth, and one pregnant female was carrying a dead fetus. The animals compared unfavorably with dolphins from an area of the gulf unaffected by the spill. BP said the report, which was the first study of the spill's impact on dolphins, was “inconclusive as to any causation associated with the spill”.
Fish and shrimps
"Disturbing numbers" of mutated fish were seen in the Gulf. Scientists and fishermen are pointing to the spill, the dispersants and chemicals used in its cleanup as the cause of these deformities which include shrimp born without eyes, fish with lesions, fish with oozing sores and, according to a local fisher-woman, "We are also finding eyeless crabs, crabs with their shells soft instead of hard, full grown crabs that are one-fifth their normal size, clawless crabs, and crabs with shells that don't have their usual spikes ... they look like they've been burned off by chemicals". The dispersants are known to be mutagenic. In Barataria Bay, Louisiana, an area "heavily impacted by oil and dispersants", 50% of shrimp were found lacking eyes and eye sockets. Another lifelong fisher-woman reported seeing "fish without covers over their gills and others with large pink masses hanging off their eyes and gills".
Prior to the spill, approximately 1/10 of 1% of Gulf fish had lesions or sores. A report from the University of Florida said that many locations showed 20% of fish with lesions, and later expeditions some as high as 50%.
A 2014 paper in the journal Science found that toxins released by the oil spill killed fish by causing cardiac arrest. The study found that even very low concentrations of crude oil can slow the pace of fish heartbeats. The study was conducted by researchers at Stanford University and the National Oceanic and Atmospheric Administration as part of the federal Natural Resource Damage Assessment process required by the Oil Pollution Act. It focused on tuna partly because the spill occurred in an area where Atlantic Bluefin tuna were spawning. The effects were considered especially problematic for fish embryos and early developing fish, because the heartbeat changes could affect the development of other organs, including the lungs and liver. BP disputed the study, raising questions about the study and the use of its findings in the damage assessment process. 
Oceanographer John Kessler estimated that the crude gushing from the well contained approximately 40% methane by weight, compared to about 5% found in typical oil deposits. Methane can potentially suffocate marine life and create dead zones where oxygen is depleted. Oceanographer Dr. Ian MacDonald believes that the natural gas dissolving below the surface has the potential to reduce the Gulf oxygen levels and emit benzene and other toxic compounds.
Entry to the food chain
Signs of an oil-and-dispersant mix were found under the shells of tiny blue crab larvae in the Gulf by researchers at Tulane University in 2010. This finding indicated that the use of dispersants had broken the oil into droplets small enough to easily enter the food chain. Marine biologists found "orange blobs" under the shells of crab larvae in "almost all" of the larvae collected from over 300 miles (480 km) of coastline stretching from Grand Isle, Louisiana, to Pensacola, Florida. According to a March 2012 study, spilled oil entered the ocean's food chain through zooplankton. Dr. Michael Roman of the University of Maryland Center for Environmental Science stated "traces of oil in the zooplankton prove that they had contact with the oil and the likelihood that oil compounds may be working their way up the food chain". Alabama researchers in July 2012 found that dispersants may have killed microscopic plankton and disrupted the food chain. Scientists commenting on the study, published in PLOS ONE, said it pointed toward "major future effects of the spill". One scientist called its findings "scary, though limited because the experiments spanned only five days".
Polycyclic aromatic hydrocarbons
Terry Wade of Texas A&M University, Steven Lohrenz of the University of Southern Mississippi and the Stennis Space Center found evidence of the polycyclic aromatic hydrocarbons (PAH), which are often linked to oil spills, and include carcinogens and chemicals that pose various risks to human health, as deep as 3,300 feet (1.0 km) and as far away as 8 miles (13 km) in May 2010, and said it likely worsened as more oil spilled. The PAHs can kill animals immediately, in high enough concentrations, and can lead to cancer. "From the time that these observations were made, there was an extensive release of additional oil and dispersants at the site. Therefore, the effects on the deep sea ecosystem may be considerably more severe than supported by the observations reported here," the researchers wrote in the journal Geophysical Research Letters. PAH's, they said, include a group of compounds, with different types at different depths. "It is possible they dissipate quickly, but no one has yet showed this".
In September 2010, Oregon State University researchers found sharply heightened levels of chemicals in the waters off the coast of Louisiana in August 2010, the last sampling date, even after the well was capped one month prior. Near Grand Isle, Louisiana, the team discovered that PAH remained at levels 40 times higher than before the spill. The PAH's were most concentrated in the area near the Louisiana Coast, but levels also jumped 2-3 fold in other spill-affected areas off Alabama, Mississippi and Florida. As of August 2010, PAH levels remained near those discovered while the spill was still flowing heavily. Kim Anderson, a professor of environmental and molecular toxicology, said that based on the findings of other researchers, she suspected that the abundant use of dispersants by BP increased the bio-availability of the PAHs. "There was a huge increase of PAHs that are bio-available to the organisms – and that means they can essentially be uptaken by organisms throughout the food chain."
The mechanism by which oil spill PAHs poison fish was reported in a 2014 paper in the journal Science, which found that PAHs kill fish by sending them into cardiac arrest. The study also found even very low concentrations of PAHs can slow fish heartbeats and disrupt the development of fish larvae. The work may have implications for mammals and other forms of vertebrate life.
Impact to beaches
A 2012 study of the sands of the contaminated beaches and marshes showed that the variety of organisms, one of the lowest links in the food chain, had dropped dramatically since the spill. The remaining species are believed to be those that favor polluted conditions and that consume hydrocarbons. This could result in long-lasting effects to the ecosystem. The lead author said, "We went from this very diverse community with an abundance of different organisms to this really (impoverished) community that was really dominated by a couple of fungal species". The authors also expressed concerns that trace minerals and metals such as mercury and arsenic deposited by the oil may cause harm to both wildlife and humans.
The use of dispersant made oil sink faster and more deeply into the beaches, and possibly groundwater supplies, according to a November 2012 a study released by Florida State University and Utrecht University in the Netherlands. The researchers found that Corexit 9500A allowed the PAHs to permeate sand where, due to a lack of sunlight, degradation is slowed.
Impact due to clean-up
The oil clean-up itself caused damage to the fragile environment. Environmentalists and oil spill veterans warned that the various rushed, sometimes untested and unnecessary methods being used in the clean-up was "wreaking havoc". "Absolutely nothing you do to respond to an oil spill is without impacts of its own," said the EPA's Lisa P. Jackson.
In Orange Beach Alabama, beach erosion and disruption of plant and animal life-cycles continued into 2011, despite repeated requests by the Mayor and other local officials to leave the area. Clean-up crews deterred tourists from visiting local hotels and beaches due to an increase in criminal activity caused by the influx of clean-up workers.
In August 2010, scientists had determined as up to 79% of the spilled oil remained in the Gulf of Mexico, under the surface. In March 2011, it was reported that thousands of pounds of oil and dispersant were collected each day from highly visible resort areas and that 17,000 lb (7,700 kg) were collected from a beach in Alabama after a winter storm.
A Coast Guard report released on 17 December 2010, said that little oil remained on the sea floor except within a mile and a half of the well. The report said that since 3 August 2010, only 1% of water and sediment samples had pollution above EPA-recommended limits. Charlie Henry of NOAA warned even small amounts of oil could cause "latent, long-term chronic effects". Ian R. MacDonald of Florida State University said even where the government claimed to find little oil, "We went to the same place and saw a lot of oil. In our samples, we found abundant dead animals."
After Hurricane Isaac in September 2012, about 565,000 pounds of oiled material traced to the spill was brought to land. This was a greater amount than had been collected in the eight months prior. The Louisiana Coastal Protection Agency criticized BP and the USCG clean-up efforts, calling for more resources to deal with the roughly 1 million barrels (160×103 m3) of oil believed to remain below water. Huge[quantify] tar mats were also uncovered during the storm, prompting beach closures.
Although some researchers thought that the damage from the spill would rapidly resolve, three years into the recovery dolphins continue to die, fish are showing strange lesions, corals in the gulf have died and oil still remains in some marsh areas.  Due to both its size and the way it was handled, there is little previous research to predict long-term effects. At the 2013 "Gulf of Mexico Oil Spill and Ecosystem Science Conference", oceanographer David Hollander presented data that showed as much as one-third of the oil released during the spill may still be in the gulf. Researchers described a phenomenon called "dirty blizzard": oil caused deep ocean sediments to clumped together, falling to the ocean floor at ten times the normal rate in an "underwater rain of oily particles". The result could have long-term effects on both humans and marine life. Commercially-fished species feed on sediment creatures, meaning oil could remain in the food chain for generations. Concern was expressed for commercially fished species such as tilefish which burrow in the sediment and feed on sediment dwelling creatures. In 2013 researchers found that a tiny amoeba-like creatures, foraminifera, that live in sediment and form the bottom of the gulf food chain, have died off in the areas that were affected by the underwater plumes that stretched out miles beyond the spill site. The foraminifera have returned in some areas but in other areas they have burrowed into the sediments, stirring them up all over again. Noting that it took several years for the herring population to crash following the Exxon Valdez oil spill, the researchers expressed concerns that it may also take years for long-terms effects to become apparent in the gulf.
- Environmental issues in the United States
- Environmental impact of the petroleum industry
- Health consequences of the Deepwater Horizon oil spill
- "Gulf of Mexico oil leak 'worst US environment disaster'". BBC News. 30 May 2010.
- "Oil Spills by the Numbers". Retrieved 2010-01-10.
- Froomkin, Dan (29 July 2010). "Scientists Find Evidence That Oil And Dispersant Mix Is Making Its Way Into The Foodchain". Huffington Post. Retrieved 2010-08-02.
- "Gulf Oil Spill Response". National Parks Conservation Association. Retrieved 2010-06-13.
- "Gulf Oil Spill, by the Numbers". CBS News (CBS). 30 April 2010. Retrieved 2010-04-30.
- Biello, David (9 June 2010). "The BP Spill's Growing Toll On the Sea Life of the Gulf". Yale Environment 360. Yale School of Forestry & Environmental Studies. Retrieved 2010-06-14.
- Shirley, Thomas C.; John W. Tunnell, Jr., Fabio Moretzsohn, and Jorge Brenner (May 2010). "Biodiversity of the Gulf of Mexico: Applications to the Deep Horizon oil spill" (Press release). Harte Research Institute for Gulf of Mexico Studies, Texas A&M University. Retrieved 2010-06-14.
- Deepwater Horizon spill threatens more species than legally protected, study finds
- Resnick-Ault, Jessica; Wethe, David (2 June 2010). "BP Oil Leak May Last Until Christmas in Worst Case Scenario". Bloomberg. Retrieved 2010-06-29.
- Collins, Jeffrey; Dearen, Jason (16 May 2010). "BP: Mile-long tube sucking oil away from Gulf well". The Washington Times. Associated Press. Retrieved 2010-06-29.
- "US says BP move to curb oil leak 'no solution'". BBC News. 17 May 2010. Retrieved 2010-07-01.
- Smith, Lewis (23 May 2011). "Deep sea fish named in world top ten new species". Fish2Fork. Retrieved 23 May 2011.
- Conservation Letters: Whale and dolphin death toll during Deepwater disaster may have been greatly underestimated by Dr. Rob Williams, et al. – Offshore Oil Drilling. Reefrelieffounders.com (30 March 2011). Retrieved 2011-04-07.
- Dolphin toll from BP oil spill far higher: study – Yahoo! News. Yahoo!! News. Retrieved 2011-04-07.
- "Massive stretches of weathered oil spotted in Gulf of Mexico". The Times-Picayune. Nola.com. 28 October 2010. Retrieved 23 October 2010.
- Migratory Birds Carry Chemicals from BP Oil Spill to Minnesota Two Years After Disaster | Audubon Magazine Blog
- Collection Report(PDF). U.S. Fish and Wildlife Service. 5 July 2010.[dead link]
- [dead link]
- Beaumont, Peter (31 March 2012). "Gulf's dolphins pay heavy price for Deepwater oil spill". The Guardian.
- Damien, Gayle (2012-11-30). "How attempts to clear up the Deepwater Horizon spill may have made it worse: Dispersant chemicals 'made oil penetrate Gulf Coast beaches more deeply'". Daily Mail. Retrieved 2013-02-03.
- Dermansky, Julie (20 April 2013). "Three Years After the BP Spill, Tar Balls and Oil Sheen Blight Gulf Coast". The Atlantic. Retrieved 29 April 2013.
- "Scientists find damage to coral near BP well". Fox News. Associated Press. 5 October 2010. Retrieved 2011-02-26.
- "Dead coral near BP spill called 'smoking gun'". MSNBC. Associated Press. 5 October 2010. Retrieved 2011-02-26.
- Gerken, James (26 March 2012). "Gulf Oil Spill: Coral Death 'Definitively' Linked To BP Spill". Huffington Post. Retrieved 2012-06-01.
- Fisher, Charles R. et al. (2012). "Impact of the Deepwater Horizon oil spill on a deep-water coral community in the Gulf of Mexico" (PDF). Proceedings of the National Academy of Sciences of the United States of America 109 (50): 20303–20308. Bibcode:2012PNAS..10920303W. doi:10.1073/pnas.1118029109. Retrieved 9 February 2013.
- BP oil spill seriously harmed deep-sea corals, scientists warn | The Guardian
- Nelson, Karen (22 February 2011). "Spike Reported in Number of Stillborn Dolphins on Coast". SunHerald.com. Retrieved 3 April 2011.
- Government tightens lid on dolphin death probe, Reuters, 25 March 2011
- [dead link]
- Kaufman, Leslie (23 March 2012). "Gulf Dolphins Exposed to Oil Are Seriously Ill, Agency Says". The New York Times (Gulf of Mexico;Louisiana). Retrieved 2012-06-01.
- "BP Oil Spill: Dolphins Plagued By Death, Disease Years After Rig Explosion". Huffington Post Canada. 12 February 2014. Retrieved 17 February 2014.
- Gander, Kashmira (17 February 2014). "Dolphins 'suffering miscarriage, lung disease, losing teeth after BP oil spill' researchers claim". The Indpendent (UK). Retrieved 17 February 2014.
- Eyeless shrimp and mutant fish raise concerns over BP spill effects | Fox News
- BP oil spill: The 'horribly mutated' creatures living in the Gulf - Yahoo! News
- Dahr Jamail. "Gulf seafood deformities alarm scientists - Features". Al Jazeera English. Retrieved 2012-06-01.
- Sahagun, Louis (February 13, 2014). "Toxins released by oil spills send fish hearts into cardiac arrest". Los Angeles Times. Retrieved 17 February 2014.
- Schleifstein, Mark (13 Feb. 2014). "BP Deepwater Horizon spill oil causes heart damage that can kill tuna, new study finds". The Times-Picayune, New Orleans. Retrieved 17 February 2014.
- "Tuna study reveals how pollution causes heart problems". The Australian. Feb. 14, 2014. Retrieved 18 February 2014.
- "Oil spill full of methane, adding new concerns". MSNBC. 18 June 2010. Retrieved 2010-06-20.
- Polson, Jim (16 June 2010). "BP Gulf Well Gushing as Much as 60,000 Barrels a Day". Bloomberg Businessweek. Bloomberg. Retrieved 2010-06-20.[dead link]
- Biello, David (July 2010). "Lasting Menace: Gulf oil-spill disaster likely to exert environmental harm for decades". Scientific American 303 (1): 16–16. doi:10.1038/scientificamerican1210-16. Retrieved 2010-06-22.
- "Oil from Deepwater Horizon disaster entered food chain in the Gulf of Mexico". Sciencedaily.com. 20 March 2012. doi:10.1029/2011GL049505. Retrieved 2012-06-01.
- Ortmann, Alice C.; Anders, Jennifer; Shelton, Naomi; Gong, Limin; Moss, Anthony G.; Condon, Robert H. (July 2012). "Dispersed Oil Disrupts Microbial Pathways in Pelagic Food Webs". PLOS ONE 7 (7): 1–9. Bibcode:2012PLoSO...742548O. doi:10.1371/journal.pone.0042548. PMID 22860136. e42548. Retrieved 2013-02-03.
- BP oil spill dispersants may have hurt Gulf of Mexico food chain, study finds | NOLA.com
- "Toxic chemicals found deep at BP oil spill site". Yahoo health. Reuters. 2 November 2010. Retrieved 2010-11-04.[dead link]
- Schneyer, Joshua (27 September 2010). "U.S. oil spill waters contain carcinogens: report". Reuters. Retrieved 2010-10-01.
- Froomkin, Dan (30 September 2010). "Researchers Found 40-Fold Increase In Carcinogenic Compounds In Gulf". Huffington Post. Retrieved 2010-10-01.
- Bik, Holly M.; Halanych, Kenneth M.; Sharma, Jyotsna; Thomas, W. Kelley (June 2012). "Dramatic Shifts in Benthic Microbial Eukaryote Communities following the Deepwater Horizon Oil Spill". PLOS ONE 7 (6). Bibcode:2012PLoSO...738550B. doi:10.1371/journal.pone.0038550. e38550. Retrieved 2013-02-03.
- Mark Schleifstein, The Times-Picayune. "BP oil spill disrupted microbes on Gulf Coast beaches, new research shows". NOLA.com. Retrieved 2012-08-15.
- New study finds microorganisms along Gulf Coast impacted by BP oil spill | wwltv.com New Orleans
- Zuijdgeest, Alissa; Huettel, Markus (November 2012). "Dispersants as Used in Response to the MC252-Spill Lead to Higher Mobility of Polycyclic Aromatic Hydrocarbons in Oil-Contaminated Gulf of Mexico Sand". PLOS ONE 7 (11): 1–13. Bibcode:2012PLoSO...750549Z. doi:10.1371/journal.pone.0050549. PMID 23209777. e50549. Retrieved 2013-02-03.
- Messy Cleanup of BP Oil Spill Damages the Gulf
- The presence of cleanup crews after oil or diesel spills often helps deter birds from (nesting in) the affected areas
- Chipman, Kim. (17 August 2010) Scientists Say as Much as 79% of Oil Remains in Gulf of Mexico. Bloomberg. Retrieved 2011-04-07.
- Jerry Cope: NASA Data Strengthens Reports of Toxic Rain on the Gulf Coast From BP Spill. Huffington Post. Retrieved 2011-04-07.
- Burdeau, Cain (17 December 2010). "Coast Guard: Little seafloor oil from Gulf spill". USA Today. Associated Press. Retrieved 2010-12-24.
- Tropical Storm Lee surge reveals tar mats on Fourchon Beach | NOLA.com
- Discovery of 'tar mat' prompts Gulf closure | Tracking the Tropics - WDSU Home
- About 565,000 pounds of oiled material from Deepwater Horizon stirred up by Hurricane Isaac | NOLA.com
- Three years after BP oil spill, USF research finds massive die-off | Tampa Bay Times
- Study: "Dirty bathtub" buried oil from BP spill - CBS News
- Nature news report
- Deepwater Horizon oil spill at the Florida Department of Environmental Protection
- 20130120 - Ethereal Islands and Ever-present Oil
- 20130127-Calm seas but troubled waters