My current research interests focus on the contamination and biogeochemistry of mercury (Hg) and carbon dioxide (CO2) in various environments, including the open ocean, marginal seas, estuaries, and freshwater systems. The primary objective of my research is to understand the exchange processes across the air-water interface. For mercury, my studies aim to quantify both wet and dry deposition, as well as gas evasion in marginal seas. Additionally, I use bioindicators like sediments and corals to reconstruct atmospheric Hg deposition and assess potential methyl-Hg contamination. Moreover, I investigate the fate and toxicity of Hg by determining the specific Hg species and its isotopic signatures in the food webs in the oceans, especially in relation to global change. My work places significant emphasis on the biogeochemical cycling of Hg in the oceans and its trophic transfer through the food chain.

Our research facilities include specialized labs for studying mercury (Hg) and carbon dioxide (CO2). We are equipped with an onboard Hg species analyzer, capable of measuring elemental Hg, methyl-Hg, and total Hg, as well as CO2 systems for assessing dissolved inorganic carbon, total alkalinity, pCO2, and pH. The Hg species analyzer was custom-built for use during field cruises. Current projects involve method development and comprehensive surveys of Hg speciation within food webs and the western North Pacific Ocean. We are also conducting stable isotope analyses for carbon, nitrogen, and mercury isotopes to investigate bioaccumulation and trophic transfer within tuna food webs in the North Pacific Ocean.