OVER A BARREL continued from Home Page
A patch of brown oil and dispersant in the Gulf of Mexico. This is sometimes described as a pudding like substance. Dr. Susan Shaw photo
In a New York Times op ed piece she wrote after the dive, she said, “In some places, the oil has mixed with an orange-brown pudding-like material, some of the 700,000 gallons of a chemical dispersant called Corexit 9500 that BP has sprayed on the spreading oil. Near Rig No. 313, technically a restricted zone, the boat stopped and I (wearing a wetsuit, with Vaseline covering exposed skin) jumped in.
“Only a few meters down, the nutrient-rich water became murky, but it was possible to make out tiny wisps of phytoplankton, zooplankton and shrimp enveloped in dark oily droplets. These are essential food sources for fish like the herring I could see feeding with gaping mouths on the oil and dispersant. Dispersants break up the oil into smaller pieces that then sink in the water, forming poisonous droplets — which fish can easily mistake for food.”
In a subsequent telephone interview, Shaw said the use of Corexit, along with the oil itself, is creating a situation that will devastate marine life throughout the water column.
“We’re looking at compound toxicity,” she said.
Studies, she said, show that the effect of petroleum-based Corexit dispersants combined with oil is far more toxic than oil alone. Marine species throughout the food web, she said, are experiencing very high exposure to “toxic packets” that could have a devastating effect on many species, from tiny phytoplankton and fish larvae to dolphins and sea turtles.
“As dispersed oil sinks to the bottom,” she said, “it has a lethal effect on the base of the food web – plankton, fish eggs and larvae – and the ‘middle men,’ the small fish like herring that are eating plankton, their food enveloped in toxic packages of oil and dispersant. Now, large toxic sub-sea plumes of dispersed oil are moving into shallow waters around the gulf, and will devastate fragile organisms, especially coral. It is well known that Corexit and dispersed oil is highly toxic to coral and the small fish associated with reef life.”
“Fish biologists predict that we will lose a generation of spawning fish. I predict we will lose more than one generation and some fish will not recover. Impacts on fragile coral reefs may be worse," she said.
A couple of scenarios will likely result from the disaster, she said, especially as toxic plumes of dispersed oil expand to the northeast and to the fragile Florida keys and other islands.
“We’ll see continuing impacts, and I think, in some areas, these will be quite large,” she said.
Most lay observers, she said, have seen images of oiled pelicans and dead sea turtles. Less visible, she said, are the impacts on the deep ocean, from tiny phytoplankton to the small fish that feed on them, and on up the chain. The impacts of the dispersed oil in the water will be long-lasting, “as oil in colder waters takes longer to weather,” she said.
Studies show, she said, that the effect of dispersant combined with oil is far more toxic than oil alone. Using less-toxic, water-based dispersant would have been a better option, she said.
Much energy now, she said, is going into controlling the oil on the surface. Not enough effort, she said, is going into siphoning the oil from elsewhere along the water column.
“Every day, it’s getting worse,” she said. “It’s just not rational. The response to the oil spill – adding petroleum solvents to a petroleum spill – is worse than the spill itself. It’s not a rational plan. It’s not a rational program.”
The use of Corexit dispersants, she said, should be stopped. “It’s not keeping the oil from shore,” she said. “Oil sheens and tar balls are now 30 miles into the marshes.”
A large but unknown amount of damage has already been done, she said, with the amount of dispersant, sprayed and injected– yet it continues to be used.
“We should stop using dispersant now and put much more effort into picking up the oil before it reaches the shore,” she said.
Shaw said she plans to return to the gulf within the next month. She said she is part of a network of scientists who will be conducting independent short-term and long-term research. One overriding goal, she said, is to see that the impacts of crude and dispersed oil are thoroughly monitored from the bottom to top of this ecosystem.
“This is the biggest environmental disaster of our lifetime,” she said. “We want to make sure this never happens again.”