Kathleen May Munson, 2013 Joint Program Student
I study chemical transformations of mercury in marine waters. Mercury is a toxin that accumulates in aquatic food chains. When mercury reacts with carbon to form the compound monomethylmercury, its concentration rapidly increases with each successive step up the marine food chain, from tiny plankton to large fish and marine mammals. As a result, organisms that rely on marine food sources, including birds, mammals, and humans, can be exposed to harmful levels of mercury. I focus on the reaction of mercury with carbon on the smallest scales, when mercury is dissolved in seawater, in order to understand how monomethylmercury forms. I measure how rapidly monomethylmercury is created and breaks down under different conditions in order to understand what environmental signals trigger increases or decreases in the monomethylmercury available to aquatic food webs.