Proc. Natl Acad. Sci. USA http://dx.doi.org/10.1073/pnas.1110052108 (2011)
The oil spill associated with the Deepwater Horizon blowout was the largest in US history. Atmospheric measurements suggest that the spill, and associated clean-up operations, led to the emission of significant quantities of air pollutants.
Ann Middlebrook of the NOAA Earth System Research Laboratory, Colorado, USA, and colleagues examined the composition and quantity of air pollutants generated by the blowout, using aircraft- and ship-based measurements taken two months after the spill. They detected a 4-km-wide plume of volatile organic compounds in the atmosphere, which they attribute to evaporation of the oil. The plume comprised a number of hazardous pollutants, including benzene and toluene. Secondary reactions in the atmosphere generated pollutants such as ozone and peroxyacetyl nitrate, a common constituent of photochemical smog.
The researchers also observed a 30-km-wide plume of organic particulate matter, generated by the evaporating hydrocarbons from the oil slick. Using a regional air-quality model, they show that winds carried these particulates to the Gulf Coast.