AAAR 37th Annual Conference October 14 - October 18, 2019 Oregon Convention Center Portland, Oregon, USA
Abstract View
Aqueous Phase Chemistry on Indoor Surfaces
MADELINE COOKE, Andrew Ault, University of Michigan
Abstract Number: 218 Working Group: The Air We Breathe: Indoor Aerosol Sources and Chemistry
Abstract Aqueous phase chemistry in aerosols and on surfaces impacts both climate and human health. Understanding these reactions is important as aqueous environments can increase rates of a reaction in comparison to the gas phase, form new species, and serve as a sink for water soluble organic and inorganic gases. Not only is there an abundance of gaseous compounds indoors capable of partitioning into the liquid phase, but there also is a greater volume of aqueous surface onto which compounds can partition due to an increase in indoor surface-area-to-volume ratios compared to outdoors. It is likely that water films on surfaces play an important role in indoor chemistry; however, there is much uncertainty in the physical and chemical properties of aqueous layers on indoor surfaces. Herein, we present a characterization of several common indoor surfaces and the associated aqueous layers under different relative humidity conditions. Physical characteristics of the water film were investigated via vibrational spectroscopic methods with a focus on the pH of the surface. To further assess the interaction of surfaces with indoor environments, aerosols of known pH were deposited onto water films of such surfaces, and the resulting change in surface pH was measured. The results of this study provide insight into potential aqueous phase reactions that could be occurring on indoor surfaces, informing predictions about the identity of indoor air pollutants and thus types of exposure to indoor occupants.