BP has used almost 600,000 gallons of the oil dispersant Corexit at the surface of the Gulf of Mexico to break-up the slick from the Deepwater Horizon spill, but concerns are growing about the environmental impact of those chemicals on the Gulf ecosystems and human residents of the area.
Federal officials have expressed the need for more toxicology studies on the dispersants, and whether dispersed oil is any less of a threat than non-dispersed oil. One toxicology expert, Dr. William Sawyer, called the products "deodorized kerosene," and a group of Louisiana fisherman and marine toxicologist Riki Ott are asking President Barack Obama to order BP to stop using the compound.
Most experts won't go that far, but even EPA administrator Lisa Jackson and NOAA administrator Dr. Jane Lubchenco admitted in a recent conference call that the effects of the dispersants are largely unknown. Most of the studies performed on the agents have been testing effectiveness on dispersing oil, not on toxicity.
"There are a diversity of types of habitats in the Gulf," Lubchenco said. "Many of them are very important in support of a variety of wildlife and fisheries. At this point many of them are at risk of being affected but we don¡¯t have any direct way to know exactly which ones or in what amount."
Over the weekend, the Environmental Protection Agency gave the go-ahead to begin using the dispersants at depth to break up the oil, another largely untested process.
The exact chemical composition of the dispersants being used is not public information, but the products are called Corexit 9527 and Corexit 9500. Corexit 9527 was used in the cleanup of the Exxon Valdez spill, and contains 2-butoxyethanol, a chemical solvent that is used in paint thinners and varnish removers, among other products.
The Agency for Toxic Substances and Disease Registry, a branch of the CDC, describes 2-butoxyethanol as a toxic compound with a host of negative effects on humans, including kidney and liver damage at high doses. The data material safety sheets for both Corexit 9527 and Corexit 9500 advise "Do not contaminate surface water," under the heading "Environmental Precautions."
Corexit 9500 is a newer formula that does not include 2-butoxyethanol. Jackson said the EPA had approved both Corexit products for use, and did not know how much of the total 582,416 gallons used was 9527 and how much was 9500.
There is also concern that Corexit may not be the best choice to break up Louisiana crude. Greenwire's Paul Quinlan reported that 12 EPA-approved dispersants were more effective on southern Louisiana crude, and some of those were less toxic than the Corexit products.
Quinlan also reports that Nalco, the company that makes Corexit, "boasts oil-industry insiders on its board of directors and among its executives, including an 11-year board member at BP and a top Exxon executive."
- posted on 08/16/2010
today¡¯s news
Every day during the Deepwater Horizon oil disaster, contractors sprayed an average 140,000 pounds of Corexit dispersant onto oil slicks on the surface of the Gulf of Mexico and into the oil being released a mile below.
View full sizeDinah Rogers, The Times-Picayune
The Mississippi River was photographed July 10 at the point where it flows into the Gulf of Mexico.
But what few in the public understood was that an equivalent amount of similar surfactant chemicals -- the active ingredient in Corexit and in household soaps and industrial solvents -- enters the Gulf each day from the Mississippi River, with more flowing in from other rivers and streams along the coast.
Surfactants are only one of a myriad of potentially harmful chemical substances delivered by the Mississippi and other rivers and streams to the Gulf each day, scientists say.
"We have abused the Gulf for years," said George Crozier, executive director of the Dauphin Island Sea Lab and associate professor of marine science at the University of South Alabama. "We have our own versions of the dead zone in Mobile Bay. The most famous is the Jubilee, which is certainly caused by nutrient-fed algae blooms and low-oxygen driven."
The surfactants in the Mississippi and other rivers are the ingredients in dishwasher detergent and industrial solvents that cause oils to disperse. They get into the Mississippi from the disposal of wastewater to sewage treatment plants and directly to the river.
According to a 1996 U.S. Geological Survey report, the median concentration of surfactants in the river was .05 parts per million. Based on the river's average flow rate, that would result in 140,000 pounds of surfactant entering the Gulf each day, said David Dzombak, director of the Steinbrenner Institute for Environmental Education and Research at Carnegie Mellon University and chairman of a National Research Council committee that authored a 2008 study of Mississippi River water quality.
Based on information released by federal officials Wednesday, an average of 140,000 pounds of dispersant a day has been used during the first 104 days of the spill.
The 2008 study Dzombak chaired, like many others, pointed at nutrients as the most obvious threats to the Gulf's ecological health, as evidenced by this week's announcement by Louisiana Marine Consortium Director Nancy Rabalais that this summer's annual low-oxygen dead zone created by those nutrients ranks among the largest ever, almost as large as the state of New Jersey.
During the past 20 years, however, researchers with the Geological Survey also have identified a variety of what they refer to as "emerging contaminants" that may also be harming organisms in the Gulf.
These include a long list of pharmaceutical and household chemicals, ingredients used to make plastics, and new herbicides and pesticides.
Former Tulane University chemical engineer Glen Boyd found that the river's water contained measurable amounts of estrogen compounds from birth control pills and of the aspirin substitute naproxin.
Geological Survey researchers Gregory Clark and Donald Goolsby estimated the river carried as much as 1,920 tons of herbicides to the Gulf in 1993, including 640 tons of atrazine, the most popular herbicide used on both farmland and residential yards.
The Mississippi River has 'always been considered the waste disposal chute,' said John McLachlan of the Tulane Center for Bioenvironmental Research.
"One of the things we know is that almost any pharmaceutical taken by human beings or given to livestock or chickens ends up in wastewater and eventually in the river," said Tulane Center for Bioenvironmental Research Director John McLachlan, an expert in the study of chemicals that can change the way sexual organs work in living things.
The amounts of hormones measured by Boyd were "enough to feminize fish in an aquarium," McLachlan said.
"I remember telling my mother living in Pittsburgh that two weeks after she flushed the toilet, I'd see it in New Orleans," he said. "The river's always been considered the back of the house here. That's why there are no windows on the back of the convention center, why it's only in the last 10 or 12 years that people have been enticed down to the river.
"It's always been considered the waste disposal chute," he said.
The next chemical he expects to see documented in the Gulf is Prozac, a popular anti-depressant already found in rivers and streams elsewhere in the country.
Understanding that oil and dispersant associated with the Deepwater spill are not the only contaminants in the Gulf does not take away from concerns about their effects, said Michael Blum, an assistant professor in Tulane's Department of Ecology and Evolutionary Biology who is studying how coastal marsh plants and the microbes that live in and around them respond to the spill.
"Those other compounds are in the background and always ongoing," Blum said. "Now we have the oil in the environment to contend with."
In some cases, that means comparisons in which the other contaminants are probably more harmful, he said, such as a potential cause of hypoxia, or low-oxygen water.
"There is a concern about a dead zone created by oil in the water," he said. "A dead zone driven by oil and not nutrients could be dwarfed, or relatively small, compared to what we already see along Louisiana's coastline on a seasonal basis. So the question is to what extent is oil in the environment making things worse."
And that's more likely to be a concern in terms of the immediate or long-term toxic effects of oil and dispersants on Gulf organisms, he said.
For instance, the chemical used as a dispersant is more toxic than the surfactants coming from dishwasher detergent and hand soap, engineered to be less toxic to humans and are already weathered in the river by the time they enter the Gulf, he said.
Blum said he's concerned that Wednesday's announcement by NOAA and other federal agencies that a significant percentage of the oil released during the spill has "disappeared" by being turned into tiny droplets or dissolved in water could be misleading. "They compared dissolved oil to sugar dissolving in water, and that's accurate in the sense that you can't see it anymore," he said. "But the next logical step to that statement is if you drink that water, are you OK? When sugar and water mix, it's not that the sugar is not there; it's just changed form and composition.
"From a human or wildlife perspective, there's still an oil presence, just a difference in its composition," he said. "The same logic applies to dispersed oil. If it's been reduced to a 100-micron level, should we feel that it poses no risk? The argument is it's remediated more quickly by microbacterial communities and that argument has weight to it because microbes in the Gulf are predisposed to metabolize oil.
"But it's not clear that the microbes are going to be at the same place, or depth as the oil, or how they will interact," he said. "You can have as many estimates as you want from the laboratory, but you can't reconstruct the environment at 3,000 or 4,000 feet."
Thus, the lack of information about the long-term effects on the marine coastal food chains is important, said Blum.
"Everyone has been concerned about the near-term, the day-to-day and week-to-week effects of the spill," he said. "We need to put more time into monitoring long-term changes and understanding the long-term trajectories" of how oil and dispersant are passed along the food chain from microbes to larger species, including humans.
"That will give us a better perspective on how the effects of this oil geyser compare to background levels of contamination from the Mississippi River," Blum said.
- posted on 08/17/2010
Press Release
A New Non-Toxic Chemical That Cleans OIl Spills Organically
Innovative concept uses organic substance to treat oil with no damage to the marine ecosystem
Los Angeles, CA (PRWEB) August 8, 2010 -- Si&F New Material
Co£¨also as Sifchem www.sifchem.com), a leading Chinese company which has developed and marketed products for the
Pharmaceutical, life science and industrial sectors for 17 years,
introduced a new product which can alleviate the danger caused by oil spills such as the recent BP well collapse in the Gulf of Mexico. The product employs a new surface-collecting concept, which is different than standard methods that disperse the oil into droplets and remain in the ocean.
The product, known as SiFast R-332, is a fluorinated organic surfactant which collects the oil and solidifies it into a form suitable for collection. It has been extensively tested for 10 years in the laboratory and is now ready for field testing by EPA certified laboratories. The company's plan is that R-332 will be the first surface collecting agent approved by the EPA for inclusion on its NCP product list, which is used by oil spill responders to determine proper treatment.
Current chemicals used to treat oil spills are known for environmental
degradation and lack of efficiency. SiFast R-332 is designed to be applied in very small amounts(.001%) over a wide surface area, which insures that as little as possible remains in the marine environment.
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