Last week, I hitched a ride on a boat that ultimately got within about 10 miles of the Deepwater Horizon disaster site.
While we were bobbing on the surface of the oil slick, one of the boat's passengers decided to try a little experiment.
He grabbed a bottle of Formula 409 off the bottom of the boat & started spraying:
As an environmentalist, my first reaction was, putting Formula 409 in the ocean?! Then I realized BP has dumped over 300,000 gallons of chemical dispersant on the spill. Replacing one tablespoon of that with Seventh Generation wouldn't help matters.
While they're not identical, both Formula 409 & BP's dispersant are essentially detergents. As you can see in the clip, the 409 had the same effect of causing the oil to clump & sink. Some of the disperant ingredients are considered trade secrets, but many are voluntarily disclosed:
The key ingredient of dispersants is a surfactant or, in layman's terms, a detergent. It is often mixed with an organic solvent or an alcohol to help it mix more thoroughly with the oil. Just like the detergent in your washing machine, it binds to both the oil and the water, reducing the surface tension that causes petroleum to form a sheen on the water's surface and allowing it to form fine particles.
What does that do?
"You're transferring the pollution, if you will, but under the right circumstances it's probably favorable," said E. Eric Adams, who specializes in environmental fluid mechanics at the Massachusetts Institute of Technology. "You use it when you are more concerned about [life] on the surface and shorelines than in the water column. It's a tradeoff," said Adams, who was on a National Academy of Sciences panel that investigated dispersants in 2005.
"Well offshore is the best place to use it," added Beth McGee, a water quality scientist at the Chesapeake Bay Foundation who was also a member of the National Academy panel. "You may be creating a toxic environment for fish, but you are preventing it from washing up on shore, which would have a much greater environmental impact. In the case of the gulf...you do everything you can to prevent it from reaching the shore."
Read much more on the spill & dispersants from NWF Senior Scientist Doug Inkley. And for all the latest news on how the oil spill is impacting the Gulf Coast's wildlife & to learn how you can help, visit NWF.org/oilspill.
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