EPA Dispersant Tests “of Very Limited Utility”

Facts matter: Sign up for the free Mother Jones Daily newsletter. Support our nonprofit reporting. Subscribe to our print magazine.


The EPA on Wednesday released the first round of information on the testing the agency has been conducting on chemical dispersants. The agency concluded that, in general, the eight dispersant products it tested have “roughly the same impact on aquatic life” and are less toxic than the oil itself. But as other scientists have pointed out, the first results were on the dispersant products alone, not on their toxicity when mixed with oil.

The EPA tests concluded that Corexit 9500, the dispersant BP has been using most in the Gulf, WAS “practically non-toxic” to fish and “slightly toxic” to shrimp. Yet Richard Denison, a senior scientist at the Environmental Defense Fund, notes that the chemicals were tested alone, rather than in combination with oil. The EPA already had most of this data on short-term toxicity, as companies are required to test that before submitting products for approval. Other studies, however, have found that the oil-dispersant combination is more toxic and thus presents more of a threat to Gulf ecosystems than the dispersant alone.

These tests also only studied how much of a dispersant is needed to kill half of the organisms exposed to it for a relatively short amount of time. Gulf organisms, however, will be exposed for much longer periods. Denison concludes that this first round of testing is “of very limited utility in answering any of the more profound questions surrounding the use of dispersants.”

Of course, the EPA cautioned this is just the first round, and there will be more in the coming weeks. But in the meantime, we don’t know a whole lot more about the impact of the chemicals BP has been dumping into the Gulf in record volumes.

THE TRUTH...

is the first thing despots go after. An unwavering commitment to it is probably what draws you to Mother Jones' journalism. And as we're seeing in the US and the world around, authoritarians seek to poison the discourse and the way we relate to each other because they can't stand people coming together around a shared sense of the truth—it's a huge threat to them.

Which is also a pretty great way to describe Mother Jones' mission: People coming together around the truth to hold power accountable.

And right now, we need to raise about $400,000 from our online readers over the next two months to hit our annual goal and make good on that mission. Read more about the information war we find ourselves in and how people-powered, independent reporting can and must rise to the challenge—and please support our team's truth-telling journalism with a donation if you can right now.

payment methods

THE TRUTH...

is the first thing despots go after. An unwavering commitment to it is probably what draws you to Mother Jones' journalism. And as we're seeing in the US and the world around, authoritarians seek to poison the discourse and the way we relate to each other because they can't stand people coming together around a shared sense of the truth—it's a huge threat to them.

Which is also a pretty great way to describe Mother Jones' mission: People coming together around the truth to hold power accountable.

And right now, we need to raise about $400,000 from our online readers over the next two months to hit our annual goal and make good on that mission. Read more about the information war we find ourselves in and how people-powered, independent reporting can and must rise to the challenge—and please support our team's truth-telling journalism with a donation if you can right now.

payment methods

We Recommend

Latest

Sign up for our free newsletter

Subscribe to the Mother Jones Daily to have our top stories delivered directly to your inbox.

Get our award-winning magazine

Save big on a full year of investigations, ideas, and insights.

Subscribe

Support our journalism

Help Mother Jones' reporters dig deep with a tax-deductible donation.

Donate