Tom Philpott writes for Grist:
We finally know the main two dispersants that BP and the U.S. government are using to treat the ongoing Gulf spill.
Both, by their maker’s own admission, have the “potential to bioconcentrate,” and both have “moderate toxicity to early life stages of fish, crustaceans, and mollusks,” according to a study by Exxon, the company that originally developed them.
Their use may be the least-bad course, given the importance of minimizing oil’s effect on coastal wetlands. But a little digging into the chemical makeup of these two substances, which are being dumped in vast quantities into the Gulf, reveals that they could potentially do far more harm than good, both to the Gulf and to humans who later eat from it.
As ProPublica reported Monday, information about dispersants is “kept secret under competitive trade laws.” I’ve spent the last several days trying to confirm what many in the ocean-ecology and public health worlds seemed to know, but no one would say officially: that two different dispersants sold under the banner of Corexit were being used in vast quantities. The Corexit brand is owned by an Illinois-based company called Nalco, which entered the dispersant business back in 1994, when it merged with Exxon’s chemical unit. (By 2004, Exxon had divested and Nalco was a standalone company, according to Nalco’s company history.)
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