This project extends upon previous work by this group on the atmospheric chemistry or organic aerosols by examining the stability and atmospheric lifetimes of a series of organic compounds found in aerosols and as such commonly used as tracers. The investigators will design, construct and employ a laboratory system for testing aqueous phase reactivity of organic tracer compounds and test a variety of candidate compounds in terms of reaction mechanisms and products in order to evaluate their relative utility as conserved tracers of regional and synoptic scale atmospheric transport through a series of laboratory experiments on natural atmospheric aerosols (such as cloud, fog, and haze) and synthetic yet representative mixtures of ambient aerosol and reagent organic compounds. Results will have important broader impacts for the interpretation of ambient receptor site data, as well as understanding the contribution of long-range transport of these compounds on radiative transfer and climate change. The project includes elements integrating study research and education through existing laboratory classes at the host institution, contributing to professional training of young scientists through graduate student support, and web-based community outreach.