Richard Denison, Ph.D., is a Senior Scientist.

To judge by the headlines and leads of stories that ran on the websites of the New York Times (“The E.P.A. on Dispersants: Cure Is Not Worse Than the Disease”) and the Washington Post (“Oil dispersant does not pose environmental threat, early EPA findings suggest”) reporting on an EPA conference call held Wednesday, you’d think the first round of test results on dispersants conducted by EPA answered all outstanding questions and gave their use a clean bill of health.

Hardly.  (Despite the misleading headlines and leads, the rest of these stories were more nuanced and more accurate.)

As I reported in a post Wednesday, the new acute toxicity data were from tests conducted on the dispersants by themselves, rather than mixed with oil – which is what the environment sees.  Moreover, the new data did little more than confirm already available data showing that currently listed dispersants exhibit relatively low acute toxicity to fish and shrimp, and that by themselves they are less toxic than oil by itself.

So despite the hoopla, the new data from this first round of testing are of very limited utility in answering any of the more profound questions surrounding the use of dispersants.  Read More »