Oil Cleanup? Dispersing the Myths

There has been much recent attention to BP’s use of so-called dispersants in the Gulf oil disaster. Dispersants are chemicals intended to break up the spilled oil, presumably to speed degradation and thus lessen some of the havoc the oil would otherwise wreak.

But there are major drawbacks with the use of dispersants, namely:

  1. They have not been thoroughly evaluated for health and safety risk:
  2. There has been little evaluation of real-world experience with their use, so no one knows whether dispersants are truly effective, or what long-term consequences might follow their widespread, prolonged use;
  3. They are not a clean-up technology, and in fact they make it impossible to conduct other actual clean-up techniques.

So let’s be clear:  dispersants do not eliminate oil; they break vast pools of it into smaller oily bits, so the oil will sink instead of washing into sensitive (and photogenic) beaches.

Why is BP using these chemicals at all? For BP, dispersants are another critical public relations tool that allows them to pretend they’re doing something about the devastation they’ve caused.

But surely there must be experience that shows dispersants can help, right? According to BP, the primary dispersant they’re using, Corexit 9500, is a “pretty effective” tool.

But a 2008 paper by oil industry researchers states that “(D)ispersant effectiveness during an incident has not been consistently reported or well-judged….This lack of information from past spills limits analysis of dispersant use…” In fact, others have noted that EPA’s list of approved dispersants includes many that were proven to be safer and more effective than Corexit.

Again, according to BP, there’s nothing to worry about with the use of their dispersants. They say that the dispersant used in the Gulf has been “rigorously tested.” Nalco, the company that makes the chemical oil-breaker (a company with ties to a former BP Executive and to a legacy of some of the chemical industry’s worst fraudulent safety testing abuses), says the product is “more than 7 times safer than dishsoap.”

The safety review of the product tells a slightly different story. The government required safety document for Corexit 9500[c1] , states “No toxicity studies have been conducted on this product.”

But EPA has approved the dispersant, haven’t they? The agency says that dispersants “are generally less harmful than the highly toxic oil leaking from the source and biodegrade in a much shorter time span.”

But even if this reassuring statement is true, the agency seems to be missing a crucial point: since dispersants don’t eliminate the oil, whether they are less harmful than oil isn’t the issue. The question is:  how harmful are dispersants plus oil, as compared to just the oil? And is the dispersant BP is using effective enough to justify the additional risks?

The answer is not reassuring. In a paper published just this year, researchers looked at how effective Corexit 9500 was at various concentrations of oil in water, and compared it to, well, nothing. The researchers concluded that Corexit in marginally oily water removes slightly more oil than nature alone.  In very oily water, it does no better than nothing.

(One company producing a new nanotech-based dispersant wants EPA to fast-track its approval for use in the Gulf. CEH has joined other scientists and health, environment and fisheries groups in opposing this even riskier experiment).

But since dispersants are so safe (according to BP, the lack of testing notwithstanding), isn’t use of dispersants worthwhile, even if BP’s dispersant is just a little more effective than nothing?

A researcher from Texas A&M University with more than forty years of studying the Gulf of Mexico implies that this is nothing more than giant science experiment on this fragile aquatic ecosystem. “What is really a big concern, and what no one seems to know, is what effect these dispersants they are using to break up the oil will have in the years to come,” Professor Norman Guinasso said. “This deep dispersion of so much oil and dispersant is unprecedented. What are the long-term effects on marine life going to be? No one has a clue right now.”

And the immediate effects of the dispersants are already here. Many Gulf clean-up workers have reported illnesses that sound eerily like those that might be expected to occur in people exposed to chemicals in Corexit. BP says the workers are just dehydrated, or maybe they have food poisoning (probably from eating bad fish). Dr. John Howard of the Centers for Disease Control (CDC) cautioned against the use of dispersants and noted that the health risks associated with the dispersant chemicals are one the most uncertain areas for health officials. He also noted that BP has failed to respond to the CDC’s request for samples of the dispersants used in the Gulf.

Like the effects from the oil itself (more on that in an upcoming post), the dispersants are likely to pose long-term threats to Gulf communities, and especially to those already hit by environmental injustices and economic distress. Corexit is already being blamed for fishery closures, and dispersants may increase threats to many species that Gulf fishermen depend on for their livelihoods.

As Marylee Orr, Executive Director of the Gulf coast environmental justice group Louisiana Environmental Action Network told MSNBC, “The dispersant and the oil together spells, we think, a lot of health problems for a lot of folks…our folks want to save the Gulf, but we don’t want them to save the Gulf at the expense of their health.”

For more on the oil spill and voices from Gulf residents, Pacifica radio’s Democracy Now reports on the spill are at