BUFFALO, N.Y. -- Tiny aerosol particles in the upper atmosphere may act like highly efficient chemical reactors, playing host to incredibly complex reactions that can create carcinogenic by-products even from the combination of fairly benign reagents, according to a paper published today by University at Buffalo chemists.
The researchers discovered that since these particles or clusters can contain up to thousands or even millions of molecules, they actually may have an amplifying effect on the reactions, causing them to play a much larger role in polluting air than previously was understood.
The work, reported in the current (March 22) issue of the Journal of Chemical Physics, may give government and industry a better handle on just how air pollution forms.
"If you're going to regulate compounds in the upper atmosphere, you have to be able to show industry what it is that happens chemically in the upper atmosphere that makes certain ones generated at ground level harmful," said James F. Garvey, Ph.D., professor of chemistry in the UB College of Arts and Sciences and lead author.
While much research has focused on which compounds are being generated in the upper atmosphere, relatively little work has examined how they are generated. Researchers generally have assumed that many pollutants form from simple reactions between two molecules that happen to bump together in the atmosphere.
Garvey and his co-authors, Dong Nam Shin, Ph.D., former post-doctoral researcher in the UB Department of Chemistry, and Robert L. DeLeon, Ph.D., UB adjunct associate professor of chemistry, decided to look at what happened when they created in their lab a gas-phase cluster of nitric oxide -- one of the most common industrial emissions -- and methanol, a combination known to be generated in the upper atmosphere.
"This was the first combination we looked at and indeed, when this nanodroplet
was exposed to ultraviolet light, it exhibited chemical reactivity,
Contact: Ellen Goldbaum
University at Buffalo