Large China oil spill threatens sea life, water

China's largest reported oil spill emptied beaches along the Yellow Sea as its size doubled Wednesday, while cleanup efforts included straw mats and frazzled workers with little more than rubber gloves.An official warned the spill posed a "severe threat" to sea life and water quality as China's latest environmental crisis spread off the shores of Dalian, once named China's most livable city.One cleanup worker has drowned, his body coated in crude."I've been to a few bays today and discovered they were almost entirely covered with dark oil," said Zhong Yu with environmental group Greenpeace China, who spent the day on a boat inspecting the spill."The oil is half-solid and half liquid and is as sticky as asphalt," she told The Associated Press by telephone.The oil had spread over 165 square miles (430 square kilometers) of water five days since a pipeline at the busy northeastern port exploded, hurting oil shipments from part of China's strategic oil reserves to the rest of the country. Shipments remained reduced Wednesday.State media has said no more oil is leaking into the sea, but the total amount of oil spilled is not yet clear.Greenpeace China released photos Wednesday of inky beaches and of straw mats about 2 square meters (21 square feet) in size scattered on the sea, meant to absorb the oil.Fishing in the waters around Dalian has been banned through the end of August, the state-run Xinhua News Agency reported."The oil spill will pose a severe threat to marine animals, and water quality, and the sea birds," Huang Yong, deputy bureau chief for the city's Maritime Safety Administration, told Dragon TV.At least one person died during cleanup efforts. A 25-year-old firefighter, Zhang Liang, drowned Tuesday when a wave threw him from a vessel, Xinhua reported.Officials, oil company workers and volunteers were turning out by the hundreds to clean blackened beaches."We don't have proper oil cleanup materials, so our workers are wearing rubber gloves and using chopsticks," an official with the Jinshitan Golden Beach Administration Committee told the Beijing Youth Daily newspaper, in apparent exasperation."This kind of inefficiency means the oil will keep coming to shore. ... This stretch of oil is really difficult to clean up in the short term."But 40 oil-skimming boats and about 800 fishing boats were also deployed to clean up the spill, and Xinhua said more than 15 kilometers (9 miles) of oil barriers had been set up to keep the slick from spreading.China Central Television earlier reported an estimate of 1,500 tons of oil has spilled. That would amount roughly to 400,000 gallons (1,500,000 liters) — as compared with 94 million to 184 million gallons in the BP oil spill off the U.S. coast.China's State Oceanic Administration released the latest size of the contaminated area in a statement Tuesday.The cause of the explosion that started the spill was still not clear. The pipeline is owned by China National Petroleum Corp., Asia's biggest oil and gas producer by volume. Friday's images of 100-foot-high (30-meter-high) flames at China's second largest port for crude oil imports drew the immediate attention of President Hu Jintao and other top leaders. Now the challenge is cleaning up the greasy plume. "Our priority is to collect the spilled oil within five days to reduce the possibility of contaminating international waters," Dalian's vice mayor, Dai Yulin, told Xinhua on Tuesday. But an official with the State Oceanic Administration has warned the spill will be difficult to clean up even in twice that amount of time. Some locals said the area's economy was already hurting. "Let's wait and see how well they deal with the oil until Sept. 1, if the oil can't be cleaned up by then, the seafood products will all be ruined," an unnamed fisherman told Dragon TV. "No one will buy them in the market because of the smell of the oil."

Non-Toxic Oil Recovery Agent

A team of chemists led by Dr. George John, Associate Professor at The City College of New York (CCNY), has developed a non-toxic, recyclable agent that can solidify oil on salt water so that it can be scooped up like the fat that forms on the top of a pot of chilled chicken soup. The agent could potentially be used to recover oil lost in the British Petroleum (BP) spill in the Gulf of Mexico, Professor John said.

In the laboratory, Professor John and colleagues added a sugar compound mixed in alcohol to diesel oil floating on top of a saline solution. "Within five minutes, the oil had gelled into a substance thick enough to be scooped up," he said. Then the team separated 80 percent of the oil from the gel using a vacuum distillation process.
The gelling agent developed by his team is environmentally benign. It uses a sugar-based molecule that can be obtained from renewable sources and is biodegradable. In addition, only a relatively small amount of the agent -- five percent of the volume of the oil being recovered -- is required for the process, which handles a range of oil from crude to vegetable oil, to work.
The BP oil spill, which began April 24, has been pouring oil into the Gulf of Mexico at the rate of 40,000 barrels per day. Current clean-up methods, which have been in use for more than 40 years, include burning, skimming oil and using chemical dispersants. The latter can be toxic to marine life and may have unknown long-term cumulative effects on the environment, Professor John pointed out.
Besides Professor John, the team included: Swapnil R. Jadhav, a graduate student in Professor John's laboratory; Dr. Praveen Kumar Vemula, a former post-doc in Professor John's lab now at Harvard-MIT Division of Health Sciences & Technology; Dr. Srinivasa R. Raghavan, Associate Professor and Patrick & Marguerite Sun Chair in Chemical and Biomolecular Engineering at University of Maryland, and Rakesh Kumar, a graduate student in Professor Raghavan's laboratory.
The team's findings will be reported July 15 in the journal Angewandte Chemie International Edition.
Materials provided by City College of New York.

Scientists say Gulf spill altering food web

Scientists are reporting early signs that the Gulf of Mexico oil spill is altering the marine food web by killing or tainting some creatures and spurring the growth of others more suited to a fouled environment.

Near the spill site, researchers have documented a massive die-off of pyrosomes - cucumber-shaped, gelatinous organisms fed on by endangered sea turtles.

Along the coast, droplets of oil are being foundinside the shells of young crabs that are a mainstay in the diet of fish, turtles and shorebirds.

And at the base of the food web, tiny organisms that consume oil and gas are proliferating.

If such impacts continue, the scientists warn of a grim reshuffling of sealife that could over time cascade through the ecosystem and imperil the region's multibillion-dollar fishing industry.

Federal wildlife officials say the impacts are not irreversible, and no tainted seafood has yet been found. But Rep. Ed Markey, D-Mass., who chairs a House committee investigating the spill, warned Tuesday that the problem is just unfolding and toxic oil could be entering seafood stocks as predators eat contaminated marine life.

"You change the base of the food web, it's going to ripple through the entire food web," said marine scientist Rob Condon, who found oil-loving bacteria off the Alabama coastline, more than 90 miles from BP's collapsed Deepwater Horizon drill rig. "Ultimately it's going to impact fishing and introduce a lot of contaminants into the food web."

The food web is the fundamental fabric of life in the Gulf. Once referred to as the food chain, the updated term reflects the cyclical nature of a process in which even the largest predator becomes a food source as it dies and decomposes.

What has emerged from research done to date are snapshots of disruption across a swath of the northern Gulf of Mexico. It stretches from the 5,000-feet deep waters at the spill site to the continental shelf off Alabama and the shallow coastal marshes of Louisiana.

Much of the spill - estimated at up to 182 million gallons of oil and around 12 billion cubic feet of natural gas - was broken into small droplets by chemical dispersants at the site of the leaking well head. That reduced the direct impact to the shoreline and kept much of the oil and natural gas suspended in the water.

But immature crabs born offshore are suspected to be bringing that oil - tucked into their shells - into coastal estuaries from Pensacola, Fla., to Galveston, Texas. Oil being carried by small organisms for long distances means the spill's effects could be wider than previously suspected, said Tulane professor Caz Taylor.

Chemical oceanographer John Kessler from Texas A&M University and geochemist David Valentine from the University of California-Santa Barbara recently spent about two weeks sampling the waters in a six-mile radius around the BP-operated Deepwater Horizon rig. More than 3,000 feet below the surface, they found natural gas levels have reached about 100,000 times normal, Kessler said.

Already those concentrations are pushing down oxygen levels as the gas gets broken down by bacteria, Kessler and Valentine said. When oxygen levels drop low enough, the breakdown of oil and gas grinds to a halt and most life can't be sustained.

The researchers also found dead pyrosomes covering the Gulf's surface in and around the spill site. "There were thousands of these guys dead on the surface, just a mass eradication of them," Kessler said.

Scientists said they believe the pyrosomes - six inches to a foot in length - have been killed by the toxins in the oil because there have no other explanation, though they plan further testing.

The researchers say the dead creatures probably are floating to the surface rather than sinking because they have absorbed gas bubbles as they filtered water for food.

The death of pyrosomes could set off a ripple effect. One species that could be directly affected by what is happening to the pyrosomes would be sea turtles, said Laurence Madin, a research director at the Woods Hole Oceanographic Institution in Cape Cod, Mass. Some larger fish, such as tuna, may also feed on pyrosomes.

"If the pyrosomes aredying because they've got hydrocarbons in their tissues and then they're getting eaten by turtles, it's going to get into the turtles," said Madin. It was uncertain whether that would kill or sicken the turtles.

The BP spill also is altering the food web by providing vast food for bacteria that consume oil and gas, allowing them to flourish.

At the same time, the surface slick is blocking sunlight needed to sustain plant-like phytoplankton, which under normal circumstances would be at the base of the food web.

Phytoplankton are food for small bait fish such as menhaden, and a decline in those fish could reduce tuna, red snapper and other populations important to the Gulf's fishing industries, said Condon, a researcher with Alabama's Dauphin Island Sea Lab.

Seafood safety tests on hundreds of fish, shrimp and other marine life that could make it into the food supply so far have turned up negative for dangerous oil contamination.

Assuming the BP gusher is stopped and the cleanup successful, government and fishing industry scientists said the Gulf still could rebound to a healthy condition.

Ron Luken, chief scientist for Omega Protein, a Houston-based company that harvests menhaden to extract fish oil, says most adult fish could avoid the spill by swimming to areas untainted by crude. Young fish and other small creatures already in those clean waters could later repopulate the impacted areas.

"I don't think anybody has documented wholesale changes," said Steve Murawski, chief scientist for the National Marine Fisheries Service. "If that actually occurs, that has a potentially great ramification for life at the higher end of the food web."

How Fast Can Microbes Break Down Oil Washed Onto Gulf Beaches?

A new Florida State University study is investigating how quickly the Deepwater Horizon oil carried into Gulf of Mexico beach sands is being degraded by the sands' natural microbial communities, and whether native oil-eating bacteria that wash ashore with the crude are helping or hindering that process.

What oceanography professors Markus Huettel and Joel E. Kostka learn will enable them to predict when most of the oil in the beaches will be gone. Their findings may also reveal ways to accelerate the oil degradation rate -- and speed matters, because toxic crude components that remain buried on Gulf Coast beaches may seep into the groundwater below.

"This enormous oil spill affects hundreds of miles of beaches in the Gulf of Mexico," Huettel said. "We can remove the oil from the beach surface, but oil is also carried deeper into the sand, and we need to understand what happens to that oil. Preventing groundwater contamination is crucial not only to Gulf Coast residents but also to coastal management and local economies like fisheries and tourism that depend on water quality."

"We will also study the effect of the dispersant known as Corexit on oil metabolism by natural microbial communities," Kostka said. "Through contacts in the field, my laboratory has acquired Corexit and source oil from the MC252 (Deepwater Horizon) well head for use in our experiments."

St. George Island, Fla., and Dauphin Island, Ala., have served as the primary research sites since early June, when the one-year study began. In addition, the researchers have obtained heavily oiled sand from Pensacola Beach, Fla., and from a barrier island off the Louisiana coast. If warranted by the oil's movement, they will also collect near-shore water and sediment samples from other Gulf beaches.

Funding for their collaborative research comes from a "RAPID" (Rapid Research Response) grant from the National Science Foundation.

Huettel and Kostka will analyze sediment cores collected from Gulf beaches to find out how much and to what depth oil washed onto the shore is carried into the sand; how rapidly microbes in the sand are breaking it down; and how the oil pollution may be impacting the structure and function of natural microbial communities that help to protect water quality on the coast.

"We'll also show how the oil itself alters the transport and filtration of oxygen-rich water into the beach by clogging the sand -- and how this clogging and resulting reduced oxygen availability in the sand affects the microbial community and degradation of buried oil," Huettel said.

Currents and winds carry the oil, and oil combined with dispersants -- chemicals that disperse the crude into very small oil droplets -- to the Gulf shores, where it washes up on sandy beaches.

Larger crude-oil accumulations such as pancake oil (round, flat accumulations of heavy crude oil) and tar balls (weathered crude oil accumulations that have been formed into ball-shaped structures) are deposited on the beach. Meanwhile, liquid oil (in the form of an oil sheen, or small dispersed droplets) can penetrate many feet deep into the permeable beach sand.

"Oil-filled water that washes up on the beach filters through the porous sediment and carries the oil with it into the sand," Huettel said. "In addition, the water-level drop between high and low tide causes a water-level drop within the beach sediment that can transport oil that has penetrated into the beach into even deeper sediment layers."

"Crude oil is a natural component that constantly seeps out of Gulf of Mexico sediments --obviously in much smaller quantities than those now caused by the drilling accident -- so native microbes have evolved that consume this oil and thereby degrade it," Kostka said. "These microorganisms include bacteria and also some microalgae that live in the water column and the sediments of the Gulf of Mexico."

Kostka said oil accumulations deposited on the beach surface are easily removed by, for example, scraping off the top layer of sand. However, the oil components that penetrate into the sand can only be removed by microbial degradation.

"If oxygen is present -- as it is in the water and in the upper layers of the beach sand -- the microbes decompose the oil aerobically (by using oxygen)," Kostka said. "This degradation process is much faster than the degradation under anaerobic conditions (when no oxygen is available), such as those found in deeper sediment layers of the beach. That's why at the site of the Exxon Valdez oil spill in Alaska, oil can still be found deeply buried in the gravel beach sediments, because anaerobic microbial degradation is slow and, in Alaska, slower still because of the cold climate."

"Unfortunately, said Huettel, "crude oil contains such harmful substances that even small amounts can kill fish larvae -- which means that oil stored in deep layers of beach sediment present a potential source of toxins to near-shore waters and groundwater."

Their NSF-funded study ("Rates and mechanisms controlling the degradation of crude oil from the MC252 spill in Gulf of Mexico beach sands") is the latest of several collaborations between Huettel and Kostka that have examined organic matter transport and degradation in Gulf sands. Florida State University (2010, July 8). How fast can microbes break down oil washed onto Gulf beaches?. ScienceDaily. Retrieved July 11, 2010, from http://www.sciencedaily.com/releases/2010/07/100707222312.htm

Pelicans rescued from oil arrive in Pinellas

A rescue effort is saving the lives of oil-covered pelicans in Louisiana. The birds are rehabilitated then relocated to Florida beaches.

The moment of freedom for thirty-two brown pelicans came Wedensday as they were released into the wild at Fort DeSoto Park.

Less than two weeks ago, oil covered each of the birds. They were captured off the coast of Southeast Louisiana.

"Most of these birds were incapable of flying. They had enough oil on them that they're kind of incapacitated," explained Cassidy Lejeune of Louisiana's Department of Wildlife and Fisheries.

After about 10 days of rehabilitation at Fort Jackson, the pelicans were healthy enough to move to a new home free of oil.

"They're amazingly resilient. These are pretty calm birds. Once we stopped moving them around they settled down and sat in their crates and never made a peep," offered wildlife veterinarian Jenny Powers.

They flew from New Orleans in a twin-engine Coast Guard plane two pelicans per cage.

So why Fort DeSoto? The decision to bring the pelicans there has to do with much more than simply avoiding oil.

"We choose release sights based on oil trajectory, based on weather and habitat," Powers offered.

Fort DeSoto offers protected beaches and a good prey base for the pelicans to feed. As they were released, a small crowd welcomed them to Florida and witnessed something unexpected happen -- the pelicans flocked together.

"I think it must be security," Laura Foster observed. "They've been traumatized, I'm sure. They've been around humans and not their normal environment. Whether they were originally part of the same flock or not, it's nice to see that they have a family."

The rescued birds have up to an 80 percent chance of survival. Some may try to migrate back to Louisiana.

To date, more than 400 oil coated birds have been rehabilitated and released.

Long-Term Fate of Gulf Oil Spill: Computer Simulations Show Oil Reaching Up the Atlantic Coastline and Toward Europe

The possible spread of the oil spill from the Deepwater Horizon rig over the course of one year was studied in a series of computer simulations by a team of researchers from the School of Ocean and Earth Science and Technology (SOEST) at the University of Hawaii at Manoa. The simulations suggest that the coastlines near the Carolinas, Georgia, and Northern Florida could see the effects of the oil spill as early as October 2010, while the main branch of the subtropical gyre is likely to transport the oil film towards Europe, although strongly diluted.

Eight million buoyant particles were released continuously from April 20 to September 17, 2010, at the location of the Deepwater Horizon oil rig. The release occurred in ocean flow data from simulations conducted with the high-resolution Ocean General Circulation Model for the Earth Simulator (OFES).

"The paths of the particles were calculated in 8 typical OFES years over 360 days from the beginning of the spill," says Fabian Schloesser, a PhD student from the Department of Oceanography in SOEST, who worked on these simulations with Axel Timmermann and Oliver Elison Timm from the International Pacific Research Center, also in SOEST. "From these 8 typical years, 5 were selected to create an animation for which the calculated extent of the spill best matches current observational estimates."

The dispersal of the particles does not capture such effects as oil coagulation, formation of tar balls, chemical and microbial degradation. Computed surface concentrations relative to the actual spill may therefore be overestimated. The animation, thus, is not a detailed, specific prediction, but rather a scenario that could help guide research and mitigation efforts.

The animation shows the calculated surface particle concentrations for grid boxes about 10-km-by-10-km in size into April 2011. For an estimated flow of oil from the Deepwater Horizon of 50,000 barrels per day over a 150 day period, a concentration of e.g. 10 particles per grid box in the animation corresponds roughly to an oil volume of 2 cubic meters per 100 square kilometer.

The oil spreads initially in the Gulf of Mexico, then enters the Loop Current and the narrow Florida Current, and finally the Gulf Stream. "After one year, about 20% of the particles initially released at the Deepwater Horizon location have been transported through the Straits of Florida and into the open Atlantic," explains Timmermann.

This animation suggests that the coastlines near the Carolinas, Georgia, and Northern Florida could see the effects of the oil spill as early as October 2010. The main branch of the subtropical gyre is likely to transport the oil film towards Europe, although strongly diluted.

The animation also shows that as the northeasterly winds intensify near Florida around October and November, the oil in the Atlantic moves closer to the eastern shores of the US, whereas it retreats from the western shores of Florida.

The narrow, deep Straits of Florida force the Florida Current into a narrow channel, creating a tight bottleneck for the spreading of oil into the Atlantic. As the animation suggests, a filtering system in the narrowest spot of the Florida Current could mitigate the spreading of the oil film into the North Atlantic.

This research was supported by the Japan Agency for Marine-Earth Science and Technology (JAMSTEC), NASA and NOAA through their sponsorship of the International Pacific Research Center in the School of Ocean and Earth Science and Technology at the University of Hawaii at Manoa. University of Hawaii at Manoa (2010, July 6). Long-term fate of Gulf oil spill: Computer simulations show oil reaching up the Atlantic coastline and toward Europe. ScienceDaily. Retrieved July 7, 2010, from http://www.sciencedaily.com­ /releases/2010/07/100706103408.htm

Oil Spills Raise Arsenic Levels in the Ocean, Says New Research

Oil spills can increase levels of toxic arsenic in the ocean, creating an additional long-term threat to the marine ecosystem, according to research published July 2 in the journal Water Research.

Arsenic is a poisonous chemical element found in minerals and it is present in oil. High levels of arsenic in seawater can enable the toxin to enter the food chain. It can disrupt the photosynthesis process in marine plants and increase the chances of genetic alterations that can cause birth defects and behavioural changes in aquatic life. It can also kill animals such as birds that feed on sea creatures affected by arsenic.

In the study, a team from Imperial College London has discovered that oil spills can partially block the ocean's natural filtration system and prevent this from cleaning arsenic out of the seawater. The researchers say their study sheds light on a new toxic threat from the Gulf of Mexico oil leak.

Arsenic occurs naturally in the ocean, but sediments on the sea floor filter it out of seawater, which keeps the levels of naturally occurring arsenic low. However, arsenic is also flushed into the ocean in wastewater from oil rigs and from accidental oil spills and leakages from underground oil reservoirs.

In the study, the researchers discovered that oil spills and leakages clog up sediments on the ocean floor with oil, which prevents the sediments from bonding with arsenic and burying it safely underground with subsequent layers of sediment. The scientists say this shutdown of the natural filtration system causes arsenic levels in seawater to rise, which means that it can enter the marine ecosystem, where it becomes more concentrated and poisonous the further it moves up the food chain.

The scientists say their work demonstrates how the chemistry of sediments in the Gulf of Mexico may be affected by the current oil leak. Professor Mark Sephton, from the Department of Earth Science and Engineering at Imperial College London, says:

"We can't accurately measure how much arsenic is in the Gulf at the moment because the spill is ongoing. However, the real danger lies in arsenic's ability to accumulate, which means that each subsequent spill raises the levels of this pollutant in seawater. Our study is a timely reminder that oil spills could create a toxic ticking time bomb, which could threaten the fabric of the marine ecosystem in the future."

Wimolporn Wainipee, postgraduate and lead author of the study from the Department of Earth Science and Engineering at Imperial College London, adds:

"We carried out our study before the leak in the Gulf of Mexico occurred, but it gives us a big insight into a potential new environmental danger in the region. Thousands of gallons of oil are leaked into the world's oceans every year from big spills, offshore drilling and routine maintenance of rigs, which means many places may be at risk from rising arsenic levels, which could in the long run affect aquatic life, plants and the people who rely on the oceans for their livelihoods."

For their research, the team analysed a mineral called goethite, one of the most abundant ocean sediments in the world, which is an iron bearing oxide.

The team carried out experiments in the laboratory that mimicked conditions in the ocean, to see how the goethite binds to arsenic under natural conditions. They discovered that seawater alters the chemistry of goethite, where low pH levels in the water create a positive change on the surface of goethite sediments, making them attractive to the negatively charged arsenic.

However, the scientists discovered that when they added oil, this created a physical barrier, covering the goethite sediments, which prevented the arsenic in the oil from binding to them. The team also found that the oil changed the chemistry of the sediments, which weakened the attraction between the goethite and arsenic.

In the future, the researchers plan to analyse other minerals such as clays and carbonates that are sediments on the ocean floor. Sediment content varies from ocean to ocean and the researchers will analyse how oil affects their ability to bind to arsenic after a spill. Imperial College London (2010, July 5). Oil spills raise arsenic levels in the ocean, says new research. ScienceDaily. Retrieved July 7, 2010, from http://www.sciencedaily.com­ /releases/2010/07/100702100144.htm

Biomedical Scientist Concerned About Effects of Oil Spill on Human Health

University of Rhode Island Pharmacy Professor Bongsup Cho knows there are cancer-causing chemicals in diesel fumes and cigarette smoke.

The biomedical scientist also knows that some of the same chemicals are found in the gooey tar balls that are being produced as a result of the oil spill in the Gulf of Mexico, which began April 20 when a rig exploded and caught fire.

But what he and other scientists have little knowledge of is the long-range impact of the spill on humans and wildlife at the cellular level.

Cho studies the effects of environmental toxins such as cigarette smoke, diesel fumes and charred meat on DNA mutation as potential triggers for cancer.

For close to 20 years, the National Institutes of Health and the American Cancer Society have funded Cho's research on mechanistic understanding of DNA damage and its consequences on mutation and repair. "Such research is crucial in the development of effective strategies for chemoprevention and drug development, as well as risk assessment," he said.

Cho said the saturated hydrocarbons found in crude oil, such as methane, hexane and octane, evaporate quickly once in the ocean because they have low boiling points.

"These are the chemicals that can cause the respiratory problems in people involved in cleanup operations, but they are not the ones necessarily known as carcinogens," Cho said.

In many cases, these volatile organic compounds evaporate quickly when exposed to sunlight and heat. "Most would evaporate before people would suffer effects from them," Cho said.

But the tar balls and remaining thick ooze washing ashore and into marshes cause more worry for Cho.

"The tar balls contain the non-volatile, benzene-like, heavily unsaturated hydrocarbons with high boiling points," Cho said. "That's where there are a lot of toxins, such as benzo[a]pyrene. This is a known human carcinogen, and it is used as a biomarker to detect human exposure to toxins."

The researcher said a carcinogen usually has mutagenic and teratogenic effects on cells, meaning it can cause mutations in DNA and cause birth defects.

A study of the blood of individuals who worked on the Exxon Valdez cleanup following the spill in March of 1989 found DNA damage in those subjects. "DNA damage in certain functionally important areas of the genome can be a precursor to various human cancers," Cho said.

While individuals can get sick when volatile organic compounds evaporate, they would have to absorb the non-volatile compounds through ingestion or actual physical contact, he added.

"It has been reported that the size of the Gulf oil spill is unprecedented, much greater than that of the the (land mass) of New England area combined. You have to wonder about the fate of the crude oil that has not come ashore and recovered and what long term effects such toxins will have on the food chain," Cho said. "The pollutants from these toxins are going to be there for a long time."

Cho is worried about another phenomena from the spill-- the orange sheen seen on the surface of the gulf.

"That orange sheen is a result of a chemical reaction involving the sun, the crude oil and the oil dispersants," Cho said. "But nobody knows what's in that color and how toxic the chemicals are. Companies keep the chemical makeup of the dispersants secret.

"Crude oil, like diesel fuel and cigarette smoke, contain thousands of chemicals, and we have studied only a few, so the big worry is the unknown activity of those chemicals we have not studied. According to the recent Cancer Advisory Board report to President Barack Obama, Americans are constantly exposed to chemicals. There are 80,000 of them, and we only know a little about them." University of Rhode Island (2010, June 25). Biomedical scientist concerned about effects of oil spill on human health. ScienceDaily. Retrieved June 28, 2010, from http://www.sciencedaily.com/releases/2010/06/100624104806.htm

NOAA Ship Thomas Jefferson Continues Deepwater Horizon Spill Study Mission

NOAA Ship Thomas Jefferson departed Galveston, Texas, June 15 to continue research on the BP Deepwater Horizon oil spill's impact on the Gulf of Mexico. During the three-week mission, the research vessel will use sophisticated acoustic and water chemistry monitoring instruments to detect and map submerged oil in coastal areas and in the deep water surrounding the BP well head.

The 208-ft. ship will also take water chemistry measurements and samples in the vicinity of Flower Garden Banks National Marine Sanctuary and collect air samples in the areas around the well head and downwind of the spill site.

The mission will build upon research conducted in the vicinity of the spill by the Thomas Jefferson June 3-11 and NOAA Ship Gordon Gunter May 27-June 4. Aboard each ship, teams from NOAA, universities, marine science institutions and other federal agencies collected water samples and employed advanced methods for detecting submerged oil while gathering oceanographic data in the area's waters.

NOAA ships Gordon Gunter and Pisces, one of NOAA's newest research vessels, are also under way as part of an ongoing effort to collect valuable data about marine mammals, sea turtles, sea birds, fish and other marine life in the Gulf. In addition to providing baseline data, the information gathered during the missions will help researchers and resources managers better understand the spill's impact on marine species and their habitat. Another NOAA ship, Oregon II, will depart Pascagoula, Miss., this week to conduct an annual shrimp stock assessment survey in the Gulf.

Meanwhile, specialized NOAA aircraft operating out of Alabama, Florida and Louisiana continue to support the Deepwater Horizon response. National Oceanic and Atmospheric Administration (2010, June 17). NOAA ship Thomas Jefferson continues Deepwater Horizon spill study mission. ScienceDaily. Retrieved June 19, 2010, from http://www.sciencedaily.com­ /releases/2010/06/100616133850.htm

Gulf Oil Spill: Mississippi River Hydrology May Help Reduce Oil Onshore

The Gulf of Mexico: what role will the Mississippi River play in oil washing ashore and into delta wetlands? One of the spill's greatest environmental threats is to Louisiana's wetlands, scientists believe. But there may be good news ahead.

Scientists affiliated with the National Center for Earth-surface Dynamics (NCED), a National Science Foundation (NSF) Science and Technology Center headquartered at the University of Minnesota, are using long-term field plots in Louisiana's Wax Lake Delta to measure the baseline conditions of, and track the effects of the oil spill on, coastal Louisiana wetlands.

Robert Twilley and Guerry Holm of Louisiana State University (LSU) are investigating the degree to which two delta wetland characteristics may help mitigate oil contamination.

Fresh water head, as it's called, the slope of the water's surface from a river delta to the sea, and residence time of river-mouth wetlands, the time it takes water to move through a wetland at a river's mouth, are important to understanding how delta wetlands will respond to the oil spill, say the researchers.

"Since the Mississippi River is currently at a relatively high stage, we expect the river's high volume of freshwater to act as a hydrologic barrier, keeping oil from moving into the Wax Lake Delta from the sea," says Twilley.

Twilley and Holm are performing baseline and damage assessments on the plants and soils of, and comparing oil degradation processes in, freshwater and saltwater Louisiana wetlands.

"The Mississippi River's 'plumbing' provides a potential benefit to reducing the movement of oil onshore from shelf waters," says Twilley.

The Mississippi's flow has been altered for flood control to protect people and infrastructure in this working delta.

River diversion structures--concrete gates built within the levees of the river--may be operated, however, to allow water to flow to specific coastal basins and floodways, says Twilley, "as a way to provide controlled floods."

The operational features of this system "downriver to the control structure near Venice, Louisiana," he says, "may provide a second line of defense against oil washing in."

But any strategy using Mississippi River hydrology must be one of clear options and tradeoffs, says H. Richard Lane, program director in NSF's Division of Earth Sciences, which funds NCED.

"As the river stage falls and protection diminishes," says Lane, "it becomes a question of how best to distribute this freshwater resource to defend the coast from the movement of oil onshore."

The answer, Twilley says, lies in the delicate balance of river, coastal and Gulf of Mexico processes "that must work in concert to benefit the incredible 'ecosystem services' this region provides to the nation."

Louisiana wetlands "play a vital role in protecting New Orleans from hurricane damage, providing habitat for wildlife, supporting economically important fisheries, and maintaining water quality," says Efi Foufoula-Georgiou, director of NCED.

"We must look at all options for protecting them for the future."

In addition to his NCED and LSU affiliations, Twilley is the recipient of an NSF rapid response oil spill grant. National Science Foundation (2010, June 18). Gulf oil spill: Mississippi River hydrology may help reduce oil onshore. ScienceDaily. Retrieved June 19, 2010, from http://www.sciencedaily.com­ /releases/2010/06/100617120720.htm

Sea creatures flee oil spill, gather near shore

Dolphins and sharks are showing up in surprisingly shallow water off Florida beaches, like forest animals fleeing a fire. Mullets, crabs, rays and small fish congregate by the thousands off an Alabama pier. Birds covered in oil are crawling deep into marshes, never to be seen again.

Marine scientists studying the effects of the BP disaster are seeing some strange phenomena.

Fish and other wildlife seem to be fleeing the oil out in the Gulf and clustering in cleaner waters along the coast in a trend that some researchers see as a potentially troubling sign.

The animals' presence close to shore means their usual habitat is badly polluted, and the crowding could result in mass die-offs as fish run out of oxygen. Also, the animals could easily be devoured by predators.

"A parallel would be: Why are the wildlife running to the edge of a forest on fire? There will be a lot of fish, sharks, turtles trying to get out of this water they detect is not suitable," said Larry Crowder, a Duke University marine biologist.

The nearly two-month-old spill has created an environmental catastrophe unparalleled in U.S. history as tens of millions of gallons of oil have spewed into the Gulf of Mexico ecosystem. Scientists are seeing some unusual thingsas they try to understand the effects on thousands of species of marine life.

Day by day, scientists in boats tally up dead birds, sea turtles and other animals, but the toll is surprisingly small given the size of the disaster. The latest figures show that 783 birds, 353 turtles and 41 mammals have died - numbers that pale in comparison to what happened after the Exxon Valdez disaster in Alaska in 1989, when 250,000 birds and 2,800 otters are believed to have died.

Researchers say there are several reasons for the relatively small death toll: The vast nature of the spill means scientists are able to locate only a small fraction of the dead animals. Many will never be found after sinking to the bottom of the sea or being scavenged by other marine life. And large numbers of birds are meeting their deaths deep in the Louisiana marshes where they seek refuge from the onslaught of oil.

"That is their understanding of how to protect themselves," said Doug Zimmer, spokesman for the U.S. Fish and Wildlife Service.

For nearly four hours Monday, a three-person crew with Greenpeace cruised past delicate islands and mangrove-dotted inlets in Barataria Bay off southern Louisiana. They saw dolphins by the dozen frolicking in the oily sheen and oil-tinged pelicans feeding their young. But they spotted no dead animals.

"I think part of the reason why we're not seeing more yet is that the impacts of this crisis are really just beginning," Greenpeace marine biologist John Hocevar said.

The counting of dead wildlife in the Gulf is more than an academic exercise: The deaths will help determine how much BP pays in damages.

As for the fish, researchers are still trying to determine where exactly they are migrating to understand the full scope of the disaster, and no scientific consensus has emerged about the trend.

Mark Robson, director of the Division of Marine Fisheries Management with Florida Fish and Wildlife Conservation Commission, said his agency has yet to find any scientific evidence that fish are being adversely affected off his state's waters. He noted that it is common for fish to flee major changes in their environment, however.

In some areas along the coast, researchers believe fish are swimming closer to shore because the water is cleaner and more abundant in oxygen. Farther out in the Gulf, researchers say, the spill is not only tainting the water with oil but also depleting oxygen levels.

A similar scenario occurs during "dead zone" periods - the time during summer months when oxygen becomes so depleted that fish race toward shore in large numbers. Sometimes, so many fish gather close to the shoreline off Mobile that locals rush to the beach with tubs and nets to reap the harvest.

But this latest shore migration could prove deadly.

First, more oil could eventually wash ashore and overwhelm the fish. They could also become trapped between the slick and the beach, leading to increased competition for oxygen in the water and causing them to die as they run out of air.

"Their ability to avoid it may be limited in the long term, especially if in near-shore refuges they're crowding in close to shore, and oil continues to come in. At some point they'll get trapped," said Crowder, expert in marine ecology and fisheries. "It could lead to die-offs."

The fish could also fall victim to predators such as sharks and seabirds. Already there have been increased shark sightings in shallow waters along the Gulf Coast.

The migration of fish away from the oil spill can be good news for some coastal residents.

Tom Sabo has been fishing off Panama City, Fla., for years, and he's never seen the fishing better or the water any clearer than it was last weekend 16 to 20 miles off the coast. His fishing spot was far enough east that it wasn't affected by the pollution or federal restrictions, and it's possible that his huge catch of red snapper, grouper, king mackerel and amberjack was a result of fish fleeing the spill.

In Alabama, locals are seeing large schools hanging around piers where fishing has been banned, leading them to believe the fish feel safer now that they are not being disturbed by fishermen.

"We pretty much just got tired of catching fish," Sabo said. "It was just inordinately easy, and these were strong fish, nothing that was affected by oil. It's not just me. I had to wait at the cleaning table to clean fish."

Scientists Locate 23-Mile Long Oil Plume Off Florida's Gulf Coast

A team of dedicated South Florida researchers from the University of Miami's Cooperative Institute for Marine and Atmospheric Studies (CIMAS) and the National Oceanic and Atmospheric Administration's Atlantic Oceanographic and Meteorological Laboratory (NOAA/AOML) were determined to check on whether oil was, as predicted, being pulled into the Loop Current and carried toward the Dry Tortugas.

The University of Miami's 96-foot catamaran the RV/F.G. Walton Smith had just completed a two-week National Science Foundation (NSF) sponsored cruise sampling the deep submerged plumes near the Deepwater Horizon well site. NOAA/AOML offered to pay for a few additional days, but the ship which is part of the University National Laboratory System, had to return to Miami on its tight schedule. The best they could do was extend the trip home by 18 hours.

Using funding provided through CIMAS, a team was rapidly assembled that included UM and CIMAS oceanographers Tom Lee and Nelson Melo, as well as a group of scientists led by Michelle Wood, director of the NOAA/AOML's Ocean Chemistry Division. A sampling plan was pulled together using particle trajectories calculated by the UM Rosenstiel School of Marine & Atmospheric Science's Coastal Shelf Modeling Group, in combination with information provided by Roffer's Ocean Fishing Forecast Service (ROFFS) and remotely sensed images from UM's Center for Southeastern Tropical Advanced Remote Sensing (CSTARS). Using these sophisticated tools, the team decided that the most likely pathway for oil to reach the Florida Keys was for it to be pulled into a counterclockwise rotating frontal eddy in the northeast corner of the Loop Current, and then south along the eastern frontal zone of the Loop Current to the Dry Tortugas.

They set out, borrowing surveying equipment from NSF scientists who were leaving the ship, including geological oceanographer Vernon Asper of the University of Southern Mississippi and Samantha Joye from the University of Georgia. As they traveled into the eddy field they saw areas of sheen, but no tar balls.

Changing course to the south, however they found an area of strong flow convergence within a southward flowing jet that resulted from flow being pulled into the eddy. Knowing that this was just the type of oceanographic feature that would concentrate any floating material, including oil, they followed it. At about the same time a U.S. Coast Guard flight that had been sent to visually survey the area spotted what they thought could be an oil slick in the area and contacted the scientists aboard the Walton Smith to have the ship get a closer look at the slick.

"As we approached, we found an extensive oil slick that stretched about 20 nm (20 miles) along the southward flowing jet which merged with the northern front of the Loop Current. The slick was made up of tar balls shaped like pancakes that went from the size of a dime to about 6 inches in diameter," said Tom Lee, UM Research Professor Emeritus and CIMAS scientist. "The combination of models and satellite images, along with our shipboard observations and ROFFS daily analysis had helped us to identify and study this previously unidentified oil plume located off Florida's southwest coast and heading toward the Tortugas."

Scientists quickly set up net tows and lowered a CTD (Conductivity, Temperature and Depth) instrument equipped with oil sampling devices into the water, collecting samples of both the oil and saltwater in the area. As they headed further south they kept looking for other tendrils oil, but increased winds made spotting tell-tale sheens more difficult. As a result they could not confirm the exact length of this southern arm of the oil slick, which they had previously inferred from their data. Samples have been provided to federally sanctioned laboratories to confirm the source of materials gathered.

"The good news is that the various approaches we are using to project its pathway seem to be yielding similar answers and guiding us properly. We need to maintain our vigilance and expand our efforts to determine the degree of risk to unique downstream resources like the Dry Tortugas and Florida Keys National Marine Sanctuary, which are vital natural environments that we need to protect," said Peter Ortner, UM Marine Biology and Fisheries professor and director of CIMAS. "NOAA Cooperative Institutes, like CIMAS, continue to stand ready to assist their federal partners with the best available science to ensure that response and restoration resources are deployed as proactively and responsibly as possible during this national emergency."

Earlier this month the National Oceanic and Atmospheric Administration (NOAA) announced its selection of UM to continue to lead its CIMAS partnership, which has been in place since 1977 to improve our understanding of climate, hurricanes, and marine ecosystems along the southeastern U.S. coast. The renewed partnership allows investigators from UM and partner institutions to receive NOAA, as well as other federal agency support for research projects, and facilitates collaboration with NOAA scientists at NOAA/AOML, National Hurricane Center, Southeast Fisheries Science Center, as well as other NOAA facilities and 18 Cooperative Institutes nationwide.

University of Miami Rosenstiel School of Marine & Atmospheric Science (2010, June 14). Scientists locate 23-mile long oil plume off Florida's Gulf Coast. ScienceDaily. Retrieved June 15, 2010, from http://www.sciencedaily.com/releases/2010/06/100614092604.htm

3-D Models of BP Oil Spill in Gulf of Mexico Made Using Ranger Supercomputer

Researchers at The University of Texas at Austin's Texas Advanced Computing Center (TACC) are using the Ranger supercomputer to produce 3-D simulations of the impact of BP's massive Gulf of Mexico oil spill on coastal areas.

With an emergency allocation of one million computing hours from the National Science Foundation TeraGrid project, the researchers are running high resolution models of the Louisiana coast to track the oil spill through the complex marshes, wetlands and channels in the area.

The researchers include Clint Dawson, professor of aerospace engineering and engineering mechanics and head of the Computational Hydraulics Group at the university's Institute for Computational Engineering and Sciences; Rick Luettich, professor of marine sciences and head of the Institute of Marine Sciences at the University of North Carolina in Chapel Hill; and Joannes Westerink, professor of civil engineering at the University of Notre Dame.

Dawson said he and his colleagues have access to highly accurate descriptions of the Louisiana, Mississippi and Texas coastlines due to earlier hurricane storm surge research.

"What our model can do that a lot of the other models can't do is track the oil spill up into the marshes and wetlands, because we have fine-scale resolution in those areas," he said.

This kind of detail will help the scientists determine how the oil may spread in environmentally sensitive areas. The team's 2-D and 3-D coastal models also will take into account the Gulf of Mexico waves, which may bring the oil closer to the Texas coast.

Of chief concern is the possibility that a hurricane moving through the gulf may bring the oil inland. The team hopes to be able to provide support for disaster responders who may need to make emergency management decisions based on the computer models.

The primary reason for using Ranger is the massive scale of the data involved in this type of modeling and simulation. The researchers receive satellite imagery of the spill from the university's Center for Space Research and download meteorological data from the National Centers for Environmental Protection every six hours. They combine these data into a 72-hour forecast at 50-meter resolution, which is 10 to 20 times more detailed than many other models being run on the spill.

TACC Director Jay Boisseau said this is one of many emergency response efforts for which TACC has provided computational power.

"Ranger gives us the ability to support an immense amount of computational research while reacting quickly to urgent needs such as hurricane predictions, swine flu outbreak scenarios and this oil spill," Boisseau said.

For each model run, the Advanced Circulation Model for Oceanic, Coastal and Estuarine Waters simulation uses 4,096 cores on Ranger for three hours. The group has been performing between one and four simulations each day.

Gordon Wells, program manager for real-time satellite remote sensing at the Center for Space Research, is a technology adviser for state emergency management efforts. He said he is optimistic that the 3-D models will show how the oil spill interacts with underwater vegetation and provide a more accurate forecast of the environmental impact the spill will have in the coming months.he University of Texas at Austin (2010, June 14). 3-D models of BP oil spill in Gulf of Mexico made using ranger supercomputer.ScienceDaily. Retrieved June 15, 2010, from http://www.sciencedaily.com/releases/2010/06/100603155723.htm

New Strain of Bacteria Discovered That Could Aid in Oil Spill, Other Environmental Cleanup

Researchers have discovered a new strain of bacteria that can produce non-toxic, comparatively inexpensive "rhamnolipids," and effectively help degrade polycyclic aromatic hydrocarbons, or PAHs -- environmental pollutants that are one of the most harmful aspects of oil spills.

Because of its unique characteristics, this new bacterial strain could be of considerable value in the long-term cleanup of the massive Gulf Coast oil spill, scientists say.

More research to further reduce costs and scale up production would be needed before its commercial use, they added.

The findings on this new bacterial strain that degrades the PAHs in oil and other hydrocarbons were just published in a professional journal,Biotechnology Advances, by researchers from Oregon State University and two collaborating universities in China. OSU is filing for a patent on the discovery.

"PAHs are a widespread group of toxic, carcinogenic and mutagenic compounds, but also one of the biggest concerns about oil spills," said Xihou Yin, a research assistant professor in the OSU College of Pharmacy.

"Some of the most toxic aspects of oil to fish, wildlife and humans are from PAHs," Yin said. "They can cause cancer, suppress immune system function, cause reproductive problems, nervous system effects and other health issues. This particular strain of bacteria appears to break up and degrade PAHs better than other approaches we have available."

The discovery is strain "NY3" of a common bacterium that has been known of for decades, called Pseudomonas aeruginosa. It was isolated from a site in Shaanxi Province in China, where soils had been contaminated by oil.

P. aeruginosa is widespread in the environment and can cause serious infections, but usually in people with health problems or compromised immune systems. However, some strains also have useful properties, including the ability to produce a group of "biosurfactants" called rhamnolipids.

A "surfactant," technically, is a type of wetting agent that lowers surface tension between liquids -- but we recognize surfactants more commonly in such products as dishwashing detergent or shampoo. Biosurfactants are produced by living cells such as bacteria, fungi and yeast, and are generally non-toxic, environmentally benign and biodegradable. By comparison, chemical surfactants, which are usually derived from petroleum, are commonly toxic to health and ecosystems, and resist complete degradation.

Biosurfactants of various types are already used in a wide range of applications, from food processing to productions of paints, cosmetics, household products and pharmaceuticals. But they also have uses in decontamination of water and soils, with abilities to degrade such toxic compounds as heavy metals, carcinogenic pesticides and hydrocarbons.

Although the type of biosurfactant called "rhamnolipids" have been used for many years, the newly discovered strain, NY3, stands out for some important reasons. Researchers said in the new study that it has an "extraordinary capacity" to produce rhamnolipids that could help break down oil, and then degrade some of its most serious toxic compounds, the PAHs.

Rhamnolipids are not toxic to microbial flora, human beings and animals, and they are completely biodegradable. These are compelling advantages over their synthetic chemical counterparts made from petroleum. Even at a very low concentration, rhamnolipids could remarkably increase the mobility, solubility and bioavailability of PAHs, and strain NY3 of P. aeruginosa has a strong capability of then degrading and decontaminating the PAHs.

"The real bottleneck to replacing synthetic chemicals with biosurfactants like rhamnolipid is the high cost of production," Yin said. "Most of the strains of P. aeruginosa now being used have a low yield of rhamnolipid. But strain NY3 has been optimized to produce a very high yield of 12 grams per liter, from initial production levels of 20 milligrams per liter."

By using low-cost sources of carbon or genetic engineering techniques, it may be possible to reduce costs even further and scale up production at very cost-effective levels, researchers said.

The rhamnolipids produced by NY3 strain appear to be stable in a wide range of temperature, pH and salinity conditions, and strain NY3 aggressively and efficiently degrades at least five PAH compounds of concern, the study showed. It's easy to grow and cultivate in many routine laboratory media, and might be available for commercial use in a fairly short time. Further support to develop the technology is going to be sought from the National Science Foundation.

"Compared to their chemically synthesized counterparts, microbial surfactants show great potential for useful activity with less environmental risk," the researchers wrote in their report. "The search for safe and efficient methods to remove environmental pollutants is a major impetus in the search for novel biosurfactant-producing and PAH-degrading microorganisms."

Collaborating on this research were scientists from Xi'an University of Architecture and Technology and Nanjing Agricultural University in China.

Subsurface Oil from Deepwater Horizon Spill in Gulf of Mexico, Say Researchers

Researchers at the University of South Florida's College of Marine Science have confirmed the presence of distinct layers of degraded oil in the deep waters of the northern Gulf of Mexico many miles from the Deepwater Horizon explosion site.

After a series of tests conducted by both USF and the National Oceanic and Atmospheric Administration, USF scientists are continuing research on the subsurface oil to determine if it can be conclusively linked to oil found at the surface of the gulf.

NOAA tests separately link the surface oil to the Deepwater Horizon well. The NOAA analysis was unable to directly link the subsurface samples to the Deepwater Horizon spill because the sample was too small to produce conclusive results.

"We have not concluded our comparison of the oils," said Ernst Peebles, USF's lead scientific investigator on the R/V Weatherbird II trip. "Preliminary results show similarities at least at the surface."

This research was funded by NOAA and led by Peebles, a biological oceanographer; Robert Weisberg, a physical oceanographer; chemical oceanographer David Hollander; and geological oceanographer David Naar.

Researchers discovered the subsurface oil after models developed by Weisberg, director of USF's Ocean Circulation Group, indicated that subsurface oil -- commonly referred to as "plumes" -- would have been pushed in that direction from the ruptured Deepwater Horizon well.

Degraded oil was found suspended at depths of 400 meters (one-quarter mile) and 1,000-1,400 meters (two-thirds to three-quarters of a mile) beneath the Gulf's surface in the form of small particles or droplets.

The 400-meter layer was approximately 30 meters (100 feet) thick, and was observed to extend for at least 45 nautical miles northeast of the Deepwater Horizon site.

The deeper 1,000-1,400 meters layer had hydrocarbons that looked identical to the 400 meter samples but were at twice the concentration. That layer was observed in deeper waters to the south approximately 24 nautical miles east of the Deepwater Horizon site.

During a May 22-28 trip on the R/V Weatherbird II, USF scientists discovered the 400-meter layer using a combination of 28 kHz sonar and an optical particle sensor.

The layer at 1,000-1,400 meters was located using particle-sensor data from depths below the range of the ship's sonar.

Water filtrations from both layers produced dark-colored filter pads, which proved the existence of particles or droplets without immediately revealing their composition or origin. USF scientists have since been using a variety of analytical approaches to characterize these materials, including gas chromatography/mass spectrometry, compound-specific and bulk stable isotope mass spectrometry, and optical fluorescence spectroscopy.

The gas chromatography/mass spectrometry analysis has already yielded conclusive results, indicating that the material retained on the filter pads is oil and not suspended sediments or the remains of decaying plant life.

This analysis also revealed that the smaller hydrocarbon molecules were largely missing from the deep oil, which is characteristic of oil that has been exposed to an early level of degradation by microbes. This could be taken as a good sign, as consumption of oil by microbes is one potentially important means of removing oil from Gulf waters. Future tests will be directed at determining conclusively if these deep oil layers are derived from natural seeps or from oil leaking from the Deepwater Horizon site.

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by University of South Florida. The original article was written by Vickie Chachere.

Gulf Oil Spill Could Widen, Worsen 'Dead Zone'

While an out-of-control gusher deep in the Gulf of Mexico fouls beaches and chokes marshland habitat, another threat could be growing below the oil-slicked surface.

The nation's worst oil spill could worsen and expand the oxygen-starved region of the Gulf labeled "the dead zone" for its inhospitability to marine life, suggests Michigan State University professor Nathaniel Ostrom. It could already be feeding microbes that thrive around natural undersea oil seeps, he says, tiny critters that break down the oil but also consume precious oxygen.

"At the moment, we are seeing some indication that the oil spill is enhancing hypoxia," or oxygen depletion, Ostrom said. "It's a good hint that we're on the right track, and it's just another insult to the ecosystem -- people have been worried about the size of the hypoxic zone for many years."

The dead zone is believed to stem from urban runoff and nitrogen-based fertilizers from farmland swept into the Gulf by the Mississippi River. Higher springtime flows carry a heavier surge each year, nourishing algae blooms that soon die and sink. Those decay and are eaten by bacteria that consume more oxygen, driving out marine life and killing that which can't move, such as coral. The dead zone can grow to the size of a small state.

With the spill overlapping a section of the dead zone, the impact on that region is unknown. As it happened, Ostrom earlier had tapped zoology major Ben Kamphuis to be on the Gulf in late May for a research cruise focused on nitrogen cycling. When the British Petroleum Deepwater Horizon offshore drilling rig blew out and sank April 20, Ostrom and collaborator Zhanfei Liu from the University of Texas at Austin quickly landed federal support to expand their inquiry.

Kamphuis, a junior from Holland, Michigan, learned far more than water sampling techniques during his week aboard the research vessel Pelican.

"Down there, (the oil spill) really affects a ton of people. I really didn't realize it before going, but after going on the trip I realized how much we can help the people in that area."

With dozens of water samples now returned to the lab, Ostrom, Kamphuis and food science sophomore Sam DeCamp, another undergraduate research associate, are setting up equipment to analyze them in the coming months. They want to know whether the oil in the water will promote oxygen starvation, and if so, how.

Oil-hungry microbes can be expected to consume more oxygen from the water as they feast on hydrocarbons, Ostrom says. But the oil slick and chemical dispersants also could reduce the flow of oxygen from the atmosphere to the ocean, and possibly reduce the sunlight available to nourish oxygen-producing marine plant life.

Financial support for the project came from the National Science Foundation and the MSU College of Natural Science.

A jack of many science trades, Ostrom is on faculty in the MSU Department of Zoology and the MSU Environmental Science and Policy Program. He is a biogeochemist who focuses his studies on the interaction of organisms with their chemical and physical environments.

Michigan State researchers were in the right place at the right time to contribute to our understanding of the effects of such a massive oil spill, he says, pointing to the oil-eating microbes as likely the biggest, if unrecognized, players in the drama.

"We're fortunate to have them," he said. "They're doing the cleanup -- not BP."

Michigan State University (2010, June 8). Gulf oil spill could widen, worsen 'dead zone'. ScienceDaily. Retrieved June 9, 2010, from http://www.sciencedaily.com­ /releases/2010/06/100607092141.htm

Oil Spill Puts Commercially Significant Cold-Water Reefs in Peril

Thousands of barrels of oil are leaking out of the Deepwater Horizon site each day. The oil ascends from depths of approximately 1502 m. (4928 ft.), but not all of it reaches the sea surface. The stratified seawater of the Gulf of Mexico captures or slows the ascent of the oil, and the addition of dispersants near the oil source produces tiny droplets that float for a considerable time in the water column and may never reach the surface.

According to Drs. Gregor Eberli, Mark Grasmueck, and Ph.D. candidate Thiago Correa of the Marine Geology & Geophysics division of the University of Miami (UM), the oil that remains in suspension in the water column and creates plumes poses a serious risk for the planktonic and benthic (sea floor) life throughout the region, including the deep-sea reefs they study.
"The deep water communities within the Gulf of Mexico and in the Straits of Florida are well hidden from us, but they include many species of cold-water corals that live in water at depths of 600 -- 1500 m. (1969 -4921 ft.) in waters as cold as 3° Celsius (37.4°F)," said Eberli. "Unlike their more familiar shallow-water counterparts, these corals do not live in symbiosis with unicellular algae called zooxanthellae, but are animals that feed on organic matter floating through the water column. We know that most of the food consumed by the cold-water corals is produced in the surface waters and eventually sinks down to the corals."
The large plumes being created by the oil spill, some of which are reported to be several miles long, sit in the water column situated between this source of food and these deep-water corals. As organic material sinks through the water column it passes through the oil plumes and is contaminated by micron-sized oil droplets.
"It is most likely that the delicate cold-water corals are not able to digest these oil-laden food particles and will perish in large numbers," said Eberli. "We are especially concerned because the migrating oil plumes have the potential to destroy or greatly diminish these deep-sea coral communities as they are carried by the currents. These corals are important because they are the foundation of a diverse ecosystem that at last count includes over 1,300 marine species, according to Dr. Thomas Hourigan at NOAA."
There is also a danger that these plumes are carried by the Loop Current from the Gulf of Mexico to the Atlantic Ocean. Deep-sea coral ecosystems are common at numerous sites from the eastern Gulf of Mexico through the Straits of Florida and northward to the Blake Plateau off North Carolina. This distribution matches the path of the Loop Current that forms from the water masses in the Gulf of Mexico, and enters the Straits of Florida to form the Florida Current and further north the Gulf Stream.
Particularly vulnerable to disturbance are deep-sea fish that form part of this ecosystem because of their late maturation, extreme longevity, low fecundity and slow growth. Deep-water coral reefs in Florida waters are the habitat of the economically valuable grouper, snapper and amberjack. These and other species inhabit hundreds of deep-water coral reefs off the coast of Florida at depths of about 300 -915 m. (1000 to 3000 feet), which were explored by Dr. John Reed from Harbor Branch Oceanographic Institute some thirty years ago. This includes the 59,500 sq. m. (~23,000 sq. mi.) of deep-water reefs off the east coast of Florida, which is now proposed as the Oculina Habitat Area of Particular Concern.
There is no known technique to clean the water column from these oil plumes, and as a consequence the hidden oases of corals in the deep, cold waters of the Gulf of Mexico, the Straits of Florida and the Blake Plateau are in severe danger of being decimated by this oil spill.

Rosenstiel School of Marine & Atmospheric Science, University of Miami (2010, June 6). Oil spill puts commercially significant cold-water reefs in peril. ScienceDaily. Retrieved June 8, 2010, from http://www.sciencedaily.com­ /releases/2010/06/100606004815.htm

Spawning Habitat of Bluefin Tuna in Gulf of Mexico: Critical Area Intersects Deepwater Horizon Oil Spill

Electronic tagging and fisheries catch data have revealed pronounced differences in preferred habitat of Atlantic bluefin tuna and yellowfin tuna in the Gulf of Mexico, despite their close ancestry, according to a new study published today in the peer-reviewed journal PLoS ONE. Bluefin tuna return to the same regions of the Gulf of Mexico during spring months to spawn. The bluefin are selecting a particular habitat along the slope waters of the Gulf of Mexico, which has unique oceanographic properties that are predictable and can be seen from satellites. Yellowfin tuna are more widely distributed throughout the warm Gulf waters and occupy the region throughout the year.

"The bluefins' habitat requirements are relatively exact so we can predict with reasonable accuracy where bluefin tuna are likely to be spawning at any given time based on oceanographic data continually being gathered by satellites and weather buoys," said lead author Steven Teo of the University of California at Davis. "This is in stark contrast to yellowfin tuna, which exhibit much more generalized environmental preferences." The fidelity to breeding areas over time detected in this study is reminiscent of salmon returning to their natal stream to spawn.
Bluefin tuna are among the most valuable fish in global markets. The International Commission for the Conservation of Atlantic Tunas (ICCAT, http://www.iccat.int/) currently manages the Atlantic bluefin tuna as two distinct populations, with western Atlantic spawners of the Gulf of Mexico forming a distinct population genetically from the eastern spawners of the Mediterranean Sea. The western Atlantic stock has suffered a significant decline in spawning stock biomass since 1950, and a 20-year rebuilding plan has failed to revive the population or the North American fishery. The failure of the Gulf of Mexico spawning population to rebuild, as well as the scope of illegal and under-reported catches -- particularly in the Mediterranean Sea -- are of such major concern that the species was recently considered by the United Nations for endangered species listing in March of 2010.
Targeted bluefin fishing has been banned in the Gulf for over twenty years, but bluefin continue to be captured accidentally on pelagic longlines, often resulting in mortality. The study shows that bluefin tuna are captured in the Gulf of Mexico from January through June each year, and the highest pelagic longline catch rates are in April and May, during the bluefin spawning season.
The authors compared environmental preferences and spatio-temporal distributions of bluefin and yellowfin tuna as revealed by pelagic longline catch rates and scientific tagging cruise conducted by the Stanford University and Monterey Bay Aquarium team coupled with oceanographic data sets. Drawing on these data, a model was developed to determine the relative probability of catching bluefin and yellowfin tuna at a given place and time. This model showed that there are two major hotspot regions within the Gulf where bycatch occurs -- one in the eastern Gulf of Mexico to the north of the Loop Current, and the other in the western Gulf of Mexico. Both regions are along the slope where the shallow continental shelf depth changes rapidly to the deep sea. It is within these hotspots that bluefin tuna prefer to spawn in circular, swirling water masses called "cyclonic eddies." These eddies are more productive and slightly cooler than surrounding warm Gulf ocean currents. Yellowfin tuna, however, are much more widely dispersed throughout the Gulf of Mexico throughout the year.
These findings indicate that it would be possible to utilize spatial management techniques to protect western Atlantic bluefin tuna on their breeding grounds in the Gulf of Mexico without compromising the yellowfin tuna fishery, which could be carried out in other areas during the critical bluefin tuna breeding times.
Unfortunately, these findings also give cause for concern in light of the recent Deepwater Horizon oil spill. "Both catch data and electronic tags indicate the Gulf of Mexico along the continental shelf is the preferred habitat of this majestic fish. I think it is amazing how precisely we can predict where the bluefin are. Unfortunately their spawning habitat overlaps the Deepwater Horizon oil accident site, and the timing of the spill coincides with the time when we expect them to be there spawning" said senior author Dr. Barbara Block of Stanford University.
Funding for this study was provided by the Lenfest Ocean Program, the Tag-A-Giant Foundation, the David and Lucile Packard Foundation, the Monterey Bay Aquarium Foundation, the National Oceanographic and Atmospheric Administration and the Disney Foundation.
Steven L. H. Teo, Barbara A. Block, Sharyn Jane Goldstien. Comparative Influence of Ocean Conditions on Yellowfin and Atlantic Bluefin Tuna Catch from Longlines in the Gulf of Mexico. PLoS ONE, 2010; 5 (5): e10756 DOI: 10.1371/journal.pone.0010756

Underwater Robot Sent to Study Deepwater Horizon Spill

The Monterey Bay Aquarium Research Institute's Division of Marine Operations, under an agreement with the National Oceanic and Atmospheric Administration (NOAA), sent a high-tech robotic submersible to the oily waters of the Gulf of Mexico. The goal is to collect information about the oil plume from the Deepwater Horizon drilling rig accident for NOAA.

Although satellites and aircraft can help show the extent of the spill at the surface, MBARI's autonomous underwater vehicle (AUV) will help researchers understand the nature and extent of any plumes of oil that may be hidden beneath the surface of the ocean.
The MBARI AUV is being deployed from the NOAA Ship Gordon Gunter in Pascagoula, Mississippi. The Gordon Gunter departed from shore on Thursday, May 27th. The AUV was launched into the waters of the Gulf for the first time on May 28, 2010.
Autonomous underwater vehicles are robotic, untethered submersibles that are programmed at the surface, then navigate through the water on their own, collecting data as they go. The MBARI AUV can measure physical characteristics of the water, such as temperature, salinity, and dissolved oxygen, detect chlorophyll from microscopic marine algae, and measure concentrations of small particles (or oil droplets) in the water.
This AUV is unique in that it carries "gulper" samplers that can collect up to ten 1.8-liter water samples while traveling through the water (or through the plume in this case). The AUV also uses cutting-edge artificial intelligence software to decide where to go and when to collect its water samples. Engineers can program the on-board computers to help the AUV find a plume and then map its boundaries, as well as take water samples both within and outside the plume.
After the AUV is recovered, its water samples will be analyzed for a variety of chemicals associated with the oil and dispersants. These samples may also be subjected to DNA analysis to determine what types of algae, bacteria, or other microorganisms are present.
This MBARI AUV can dive to 1,500 meters (5,000 feet) below the surface -- deep enough to collect water samples near the seafloor in the vicinity of the oil spill. The vehicle typically follows a "roller-coaster" path through the water, which allows its instruments to monitor a cross-section of the ocean.
MBARI engineers and scientists have been developing this AUV for almost a decade, and added its water-collection capability in 2007. One of the team's goals has been to replace expensive shipboard measurements with information collected automatically by the AUV. The vehicle has been used to study red tides and other algal blooms and to understand and perform long-term water quality monitoring.
The MBARI team is excited by the prospect that their vehicle may be useful in understanding the Gulf oil spill. Information about where oil is spreading beneath the ocean surface will help biologists and others understand the effects of this catastrophic event.
"MBARI's AUV and gulper system provides a surveillance and sample collection capability that is complementary to other tools being deployed to understand the fate of the subsurface plume of oil and dispersant." said MBARI President and Chief Executive Officer Chris Scholin. "Coordinating this response in partnership with government and academic institutions is not only important for providing much-needed fundamental information on the spill and its impacts, but also serves as a valuable learning experience for understanding how to respond to such incidents in the future."

The above story is reprinted (with editorial adaptations by ScienceDaily staff) from materials provided by Monterey Bay Aquarium Research Institute.