1C-O2-1800 PDF
頭髪の水銀同位体分析による水銀暴露限推定
The biogeochemical cycle of mercury, Hg, in the environment, and its impact to humans and wild animals, especially in the form of methylmercury, MeHg, has been studied for many decades. The international treaty, Minamata Convention on Mercury, was agreed in 2013 in order to protect human health and the environment from the adverse effect of mercury.
The utility of Hg isotopic ratios in human hair has been discussed to understand exposure route(s) of MeHg. Relatively large mass independent fractionation (MIF), the deviation of measured isotopic ratios from those theoretically predicted from mass dependent fractionation (MDF), were occasionally observed in odd-mass-number isotopes of Hg (199 and 201) and were attributed to photochemical reactions in the environment. Previous studies show that MIF of the odd-mass isotopes in human hair samples vary with the type and quantity of food (particularly seafood) consumed. In this conference, analytical methods of Hg isotopic measurement using the cold vapor MC-ICP-MS, and Hg isotopic compositions of various human hair samples (gold miners, Japanese, European, and American) will be introduced.