Environment: New study shows dispersant makes oil up to 52 times more toxic to Gulf of Mexico microorganisms

Small grazers at the base of the food chain most directly affected


Followup studies after the 2010 Deepwater Horizon oil spill call into question the extensive use of chemical dispersants. Photo courtesy NOAA.

By Summit Voice

FRISCO — The massive amounts of oil that spilled into the Gulf of Mexico after BP’s Deepwater Horizon drill rig exploded was devastating to marine life, but the dispersant used in the aftermath to try and break down the oil slicks may have been even worse for some species, according to new research done by scientists with the Georgia Institute of Technology and Universidad Autonoma de Aguascalientes, Mexico.

Based on laboratory toxicity tests, the study found that the oil-dispersant mix was up to 52 times more toxic to tiny rotifers, microscopic grazers at the base of the Gulf’s food chain.

The researchers tested a mix oil from the spill and Corexit, the dispersant required by the Environmental Protection Agency for clean up, on five strains of rotifers. Rotifers have long been used by ecotoxicologists to assess toxicity in marine waters because of their fast response time, ease of use in tests and sensitivity to toxicants. Continue reading

Dead coral is ‘smoking gun’ for oil spill damage in Gulf

Direct impacts from oil and dispersants and oxygen depletion suspected in die-off

On this coral, some apparently living tissue can be seen at the top right and areas covered by brown material on the left. A bard skeleton is on the bottom right. The most normal looking starfish in the picture is on the left branch, but all are more tightly coiled and immobile than normal. Credit: Lophelia II 2010; NOAA OER and BOEMRE

By Summit Voice

SUMMIT COUNTY — Federally funded researchers in the Gulf of Mexico last week discovered patches of dead and dying coral they say is most likely linked with the oil that spewed from BP’s failed deep water well last summer.

“We discovered a community of coral that has been impacted fairly recently by something very toxic … The proximity of the site to the disaster, the depth of the site, the clear evidence of recent impact, and the uniqueness of the observations all suggest that the impact we have found is linked to the exposure of this community to either oil, dispersant, extremely depleted oxygen, or some combination of these or other water-borne effects resulting from the spill,” biology professor Charles Fisher said in a Nov. 5 press release issued by Penn State. Continue reading


Get every new post delivered to your Inbox.

Join 6,972 other followers