A fascinating sub-plot within the Deepwater Horizon disaster concerns the 4.3m litres of chemical dispersants that BP and its contractors have sprayed and pumped into and onto the spill, in an effort to break up the oil.
Most experts accept that the Corexit dispersants, made by Illinois-based Nalco, have reduced pollution along the Gulf coast. But many environmental scientists are concerned that marine life in the deep waters may pay a heavy price, if the chemicals have increased the amount of oil dispersed in “clouds” or “plumes” through the sea.
Although people have known roughly what Corexit contains – surfactants and emulsifiers, alcohols, light petroleum distillate – objective assessment of the effect and toxicity of Corexit has been hampered by the Nalco’s stubborn refusal to release publicly the full list of chemical ingredients, on grounds of commercial confidentiality.
The company made details available to the Environmental Protection Agency but said it would supply them to others only if they signed a non-disclosure agreement.
But last night Nalco finally gave in to pressure, after the EPA listed some of the ingredients on its website – apparently without the company’s permission. I received an email from Nalco at 11.20pm (London time) letting me know that it had posted the full ingredients list on its website.
The six ingredients have formidable chemical names but they will mean a lot to marine toxicologists. For example it is now clear that the controversial alcohol called 2-butoxy-ethanol is in Corexit 9527, the version used in limited quantities soon after the spill started on April 20, but not in Corexit 9500, the main dispersant used in the Gulf. The latter contains 1-(2-butoxyl-1-methyloxy)-propanol.
If only Nalco had been more open sooner. Some disasters are so serious that the normal rules of business confidentiality must be relaxed.
