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In a teleconference with journalists, environmental scientists underlined that the EPA needs to stay vigilant. "It's absolutely essential that aggressive monitoring takes place," Jeffery Foran, president of the Midwest Center for Environmental Science and Public Policy, said. He said the agency should urgently look at specific locations where dioxin, a byproduct of the chemical industry that is stored in the tissues rather than degrades with time, was stored.
By Foran's estimate, millions of pounds (kilogrammes) of toxic waste was stored in the New Orleans area, including two pounds (900 grammes) of dioxin. "Dioxin is a very toxic chemical, and if it's released into the environment, accumulates very quickly," said Foran.
If only one percent of the stored amount is released and only one percent of that makes it into the Gulf of Mexico, that would be sufficient to contaminate 20 million fish - itself enough to trigger warnings not to eat the fish, Foran said.
Another area of concern is the runoff from untreated sewage, which would encourage oxygen-starving blooms of algae in the sea and Lake Pontchartrain, which abuts New Orleans, said Hans Paerl, professor of marine and environmental science at the University of North Carolina.
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