title: Isotopic fractionation during the uptake and elimination of inorganic mercury by a marine fish.
abstract: This study investigated the mass dependent (MDF) and independent fractionation (MIF) of stable mercury isotopes in fish during the uptake and elimination of inorganic species. Mercury accumulation during the exposure led to re-equilibration of organ isotopic compositions with the external sources, and elimination terminated the equilibrating with isotope ratios moving back to the original values. Generally, the isotopic behaviors corresponded to the changes of Hg accumulation in the muscle and liver, causing by the internal transportation, organ redistribution, and mixing of different sources. A small degree of MDF caused by biotransformation of Hg in the liver was documented during the elimination, whereas MIF was not observed. The absence of MIF during geochemical and metabolic processes suggested that mercury isotopes can be used as source tracers. Additionally, fish liver is a more responsive organ than muscle to track Hg source when it is mainly composed of inorganic species.
authors.affiliation: Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong.
authors.forename: Xiaoyu
authors.initials: X
authors.lastname: Xu
authors.affiliation: Division of Life Science, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong. Electronic address: wwang@ust.hk.
authors.forename: Wen-Xiong
authors.initials: WX
authors.lastname: Wang
mesh_terms: D000818:Animals; D001711:Biotransformation; D005591:Chemical Fractionation; D004784:Environmental Monitoring / Q000379:methods*; D008099:Liver / Q000378:metabolism; D008628:Mercury / Q000032:analysis / Q000493:pharmacokinetics*; D008629:Mercury Isotopes / Q000032:analysis / Q000493:pharmacokinetics*; D008962:Models, Theoretical; D010473:Perciformes / Q000378:metabolism*; D014018:Tissue Distribution; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000493:pharmacokinetics*
chemical_list: D008629:Mercury Isotopes; D014874:Water Pollutants, Chemical; D008628:Mercury
keywords: Inorganic mercury; Internal distribution; Liver; Mass dependent fraction; Stable mercury isotopes