J. Am. Chem. Soc. doi: 10.1021/ja8041965 (2008)

Organic compounds in the lower atmosphere can be attacked by the particles they are sitting on, according to researchers at the University of California, Irvine.

Lab-based experiments by Barbara Finlayson-Pitts and her colleagues show that airborne sea-salt particles containing nitrate or nitrite ions can produce reactive hydroxyl radicals that attack the organic compounds adsorbed onto the particles' surfaces. It was previously thought that oxidation of these organics occurred through attack from outside by ozone or hydroxyl radicals.

Nitrate and nitrite ions are known to be present in many atmospheric particles and in the polar snowpacks. On the basis of the group's experiments, Finlayson-Pitts says it is highly likely that this bottom-up oxidation is happening in air, and could be contributing to atmospheric chemistry.