Reuters 20 May 10;
(Reuters) - Tar balls found on beaches in the Florida Keys this week are not from the Gulf of Mexico oil spill leaking from a well owned by BP, the U.S. Coast Guard said on Wednesday, citing laboratory tests.
But tar balls linked to the spill have been found elsewhere on the Louisiana and Alabama coastlines, raising concerns about the disaster's ecological impact.
Following are some facts about tar balls:
- They are the remnants of crude oil dumped into the ocean by marine vessels or, in this case, by a blown-out undersea well. They are "little, dark-colored pieces of oil that stick to our feet when we go to the beach," according to the National Oceanic and Atmospheric Administration.
- During the initial stages of a spill, the oil will spread into a thin slick, leaving it susceptible to tearing by wind and wave action. The smaller patches that result often disperse over a wide area and some of the crude mixes with water to form an emulsion that looks like chocolate pudding.
- This mix is thicker and stickier than the original oil in the spill, but it can still be torn by wind and waves. The smaller pieces it breaks into are tar balls.
_ They can be as big as pancakes but are mostly coin-sized, according to NOAA.
THREATS TO HUMAN HEALTH/WILDLIFE
- Tar balls "are very persistent in the marine environment and can travel hundreds of miles," NOAA said
- "For most people, an occasional brief contact with a small amount of oil, while not recommended, will do no harm. However, some people are especially sensitive to chemicals, including the hydrocarbons found in crude oil," it said. "They may have an allergic reaction or develop rashes."
- Sea turtles are known to eat tar balls. Dr Gilly Llewellyn, the Oceans Program Manager for WWF-Australia, a conservation group, said tar balls can "attract a curious or hungry turtle" with often fatal results.
- Tar balls can also heat up and ooze into the sand, fouling crucial nesting habitat for turtles, said John Hocevar, the Oceans Campaign Director for Greenpeace USA.
TAR BALL CLEAN UP
- "There is no magic trick to making tar balls disappear. Once tar balls hit the beaches, they may be picked up by hand or by beach-cleaning machinery. If the impact is severe, the top layer of sand containing the tar balls may be removed and replaced with clean sand," NOAA said.
(Sources: Reuters, NOAA, WWF, Greenpeace)
(Compiled by Ed Stoddard)
Gulf oil spill chemical dispersant too toxic, EPA orders
BP has 24 hours to chose another form of dispersant as toxicity of Corexit raises concerns among scientists
Suzanne Goldenberg, guardian.co.uk 20 May 10;
The Obama administration has ordered BP to use a less toxic form of chemical dispersant to break up the oil spill in the Gulf of Mexico.
The decision, first reported in the Washington Post, comes only hours after Congress heard devastating testimony from BP executives and scientists on the high toxicity of two forms of Corexit, and their relative ineffectiveness against the type of crude now polluting the Gulf. The two versions of the chemical being used on the spill are banned in the UK because they are damaging to sealife.
The Washington Post reported this morning that the Environmental Protection Agency has given the oil company 24 hours to choose a less toxic form of dispersant. Once approved by the EPA, BP will have 72 hours to deploy the new chemicals.
The heavy reliance on chemical dispersants to break up the spill has raised increasing concern among scientists and environmentalists. More than 600,000 gallons of chemicals have been sprayed on the surface of the Gulf with another 55,000 injected directly into the oil billowing out of the ocean floor.
Scientists say the chemicals could be doing more for the oil company's PR, than the overall clean-up of the Gulf. The chemicals that break up the oil in small droplets help prevent giant tides of oil washing up on shore, with their disturbing images of oil-encrusted wildlife.
But they are carcinogenic, mutagenic, and highly toxic, and it is unclear how much damage they are causing to marine life in deep water – a risk acknowledged by the EPA chief, Lisa Jackson.
Corexit has never been used in such high quantities before, Jackson told Congress earlier this week. "There has been a real reliance on them, maybe more than anybody thought would ever happen." Jackson said. She added: "I'm amazed by how little science there is on the issue."
It is also unclear what – if any – effect the use of Corexit has on the course of the spill, especially if it gets caught in the powerful loop current. "The injection of dispersants are really likely to change the transport," Richard Camilli, an oceanographer at the Woods Hole Institute, told Congress this week.
The disclosure deepened fears in the scientific community that BP's mode of cleaning up the spill could be compounding the long-term environmental damage.
The scientists say there are more powerful, less toxic dispersants available than Corexit. Members of Congress suggested this week that BP chose Corexit because of links between the oil industry and the manufacturer, Nalco Holding. Nalco has a former BP executive on its board.
"Why would you use something that is much more toxic and much less effective, other than you have a corporate relationship with the manufacturer?" asked Jerrold Nadler, a Democratic congressman from New York told a hearing on Wednesday. The EPA had approved 14 dispersants for use on the spill, including the two versions made by Corexit.
The controversy over Corexit also exposed the Obama administration to additional criticism that its scientific agencies have been too compliant with BP. In addition to sanctioning the use of Corexit, EPA has come under fire for withholding test results on the toxicity of the water close to shore.
Meanwhile, the national oceanic and atmospheric administration, which has charge of the oceans and forecasting, has been criticised for underestimating the scale of the disaster.
Independent scientists have dismissed Noaa's estimate that oil was flowing out of the ocean floor at 5,000 barrels a day, and say the agency has been slow to assess the damage caused by the underwater plume of oil.
Scientists studying newly released video footage of oil billowing out of the broken pipe on the ocean floor have put the flow rate as high as 100,000 barrels a day. The scientists are also demanding access to Noaa testing of deep water samples.
