At the time of the spill, BP drew tremendous criticism from both the federal government and Gulf scientists for using chemical dispersants Corexit 9500 and Corexit EC 9527, largely because of the Nalco chemicals’ high toxicity as compared to other dispersant products. In addition, the EPA became concerned that BP was using too much dispersant, and demanded BP take steps to limit dispersant use. In the end, BP’s application of dispersant was unprecedented – no other company had ever applied dispersant at such depths or at such a high volume. Today, new studies are beginning to surface that raise concern over the impact the dispersants may have on the Gulf’s ecosystem.

A study published in the online science journal PloS One by Alice Ortmann showed that dispersants and dispersed oil “significantly reduced” the growth of phytoplankton and ciliates – essentially, fish food. The study used water from Mobile Bay, and placed the water in 55-gallon drums. Thereafter, researchers added oil, dispersant or both to the drums in the same proportions found in the oil spill. The results were shocking. Drums that held dispersant or dispersed oil showed a significant drop in life forms, while plankton organisms increased in numbers in just oily water. “In those tanks, all of the energy seems to get trapped in the bacterial side,” said Ms. Ortmann. “There were lots of bacteria left but no bigger things. It’s like the middle part of the food web is taken away.”

Brian Crother, a biology professor at Southeastern Louisiana University, called the findings scary, but limited, because the experiments only spanned five days. He observed: “If these guys are on the money, they have pointed to something really disastrous happening in the Gulf.” Michael Crosby, a senior vice president for research at Mote Marine Laboratory in Sarasota, Fla., believes that the study was extremely well done. He said that if they would “go a couple of steps beyond their findings, I think we’re going to see these things happening and it’s going to take years for them to be seen.” Garret Graves, chairman of the Coastal Protection and Restoration Authority of Louisiana, says that they are still reviewing the study. He did say, however, that Louisiana “can say that the use of dispersants in the volume and conditions under which they were applied was unprecedented.”

Gulf States and the U.S. Government continue to perform their own studies to assess environmental damage caused by the spill as part of the Natural Resource Damage Assessment process. Of particular concern to scientists are the alarming occurrences of dolphin die-offs, which have been occurring with regularity since the oil spill occurred in 2010. Based on all we have learned during the litigation, we are greatly concerned over BP’s use of the chemicals mentioned above. We will continue to monitor this issue as more information becomes available. If you have any questions, contact Parker Miller at 800-898-2034 or by email Parker.Miller@beasleyallen.com.

Source: MSNBC.COM; nola.com; e! Science News