The Environmental Protection Agency (EPA) has finally disclosed the chemical identities of the ingredients of the dispersants being used on the oil spill in the Gulf of Mexico. Until now, the public was only provided the limited information available in the dispersants' material safety data sheets (MSDS). The MSDSs for the dispersant, known as Corexit, were produced by the dispersant's manufacturer, Nalco Company. The MSDSs provide very little information, hiding chemical identities by labeling them "proprietary" or omitting them entirely.

The EPA's oil spill response website now lists eight specific chemical identities comprising the two versions of Corexit now known to be in use in the Gulf. By contrast, the Corexit EC9600A MSDS provides only two specific chemical ingredients and one reference to a generic "Organic sulfonic acid salt," whose identity is "proprietary." Without knowing exactly what is in the dispersants, tracking them and studying their impacts is near impossible.

Nalco has claimed that Corexit "is a simple blend of six well-established, safe ingredients that biodegrade, do not bioaccumulate and are commonly found in popular household products…The COREXIT products do not contain carcinogens or reproductive toxins."

The EPA website lists eight ingredients – not the six referred to by Nalco. Among the ingredients is 2-butoxy ethanol, which possesses the following characteristics:

• 2-Butoxy Ethanol can affect you by ingestion and may be absorbed through the skin.
• 2-Butoxy Ethanol should be handled as a CARCINOGEN--WITH EXTREME CAUTION.
• Contact can irritate the skin and eyes with possible eye damage.
• Inhaling 2-Butoxy Ethanol can irritate the nose and throat.
• 2-Butoxy Ethanol can cause nausea, vomiting, diarrhea and abdominal pain.
• Exposure can cause headache, dizziness, lightheadedness, and passing out.
• 2-Butoxy Ethanol may damage the liver and kidneys.

More than 1,121,000 gallons of dispersant have been dumped into the Gulf of Mexico. Such quantities are unprecedented and never before have dispersants been used at such extreme ocean depths. Scientists do not know what the environmental and public health impacts will be. There have been reports of workers who might have been exposed to the dispersant getting sick.

The rules governing disclosure of alleged trade secrets clearly provide for the disclosure of chemical identities in the case of an emergency. As OMB Watch mentioned previously, the rules "contain emergency provisions that allow the EPA to disclose CBI under conditions where public health and the environment face 'imminent and substantial danger' or 'an unreasonable risk of injury.'"

After weeks of gallon after gallon pouring into the Gulf, finally the public is given the most basic information crucial to monitoring the fate and impacts of these chemicals. EPA had the authority to act all along; its decision to now disclose the ingredients demonstrates this. Yet it took a public outcry and weeks of complaints for the agency to act and place the public's interest ahead of corporate interests.