By Deborah Zabarenko
Washington - Dispersant chemicals used to break up oil from the BP spill are generally less toxic to test species than oil alone, US Environmental Protection Agency data released on Monday showed.
EPA researchers tested the toxicity of eight kinds of dispersants, including Corexit 9500A, the only such chemical BP has said it used on the spill. The test species were juvenile mysid shrimp and small fish found in the Gulf of Mexico.
Researchers tested the toxicity of Louisiana sweet crude oil alone and on mixtures of this oil with each of the eight dispersants.
Paul Anastas, EPA's assistant administrator for research and development, said the eight dispersants have similar toxicities to one another and to Louisiana sweet crude oil alone.
"Dispersant-oil mixtures are generally no more toxic to the test species than oil alone," Anastas told reporters in a telephone briefing. "They would generally be categorised in the moderate range."
No dispersant has been used on the BP spill in the Gulf of Mexico since July 19, Anastas said. With the well sealed and with permanent killing of the well in prospect, that is likely to continue, but he noted.
He said the EPA and President Barack Obama were committed to "long-term restoration and recovery of the Gulf Coast". - Reuters