LEAPS-MPS: Exploration of heterogenous reactions of mercury in the Arctic environment

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This award is supported by the Environmental Chemical Sciences Program and the Broadening Participation Program in the Division of Chemistry. Professor Asaduzzaman at the Pennsylvania State University Harrisburg and his students study the reactions of oxidized mercury species with snow and ice by performing quantum chemical calculations. Mercury is a toxic element that poses severe health issues to the mammalian and human body. It can be transported long distances via the atmosphere and magnify in aquatic food ecosystems. After oxidation in presence of halogens, ozone, and nitro compounds in the Arctic atmosphere, it is deposited on snow and ice surfaces. The oxidized mercury compounds then diffuse through the ice and reach the aquatic environment, where they convert into methylmercury, which is then readily taken up by plankton and is biomagnified in the food web. This project focuses on characterizing the elementary steps for the interactions of oxidized mercury compounds with snow and ice, which control the process for mercury reaching the aquatic environment. This research has potential to understand the mechanism for mercury deposition, reduction, and diffusion on the Arctic surface. The project provides research opportunities for multiple undergraduate students and a high school teacher through a research experience for teachers program. The research will focus on calculating the atomic scale interaction of oxidized mercury with ice and snow using the quantum chemical methodologies. The project will explore the deposition of oxidized mercury on the ice/snow surface, and the reduction and re-emission of deposited mercury into the atmosphere. This project can help understand many reactions of mercury with ice and snow, diffusion of deposited mercury into the ice, and conversion of inorganic to organic mercury compounds. The results will aid in determining the rate-limiting steps in the mercury oxidation-reduction processes, and ultimately in developing more accurate global atmospheric mercury models.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.