Determination of isotopic composition of atmospheric mercury in urban-industrial and coastal regions of Chiba, Japan, using cold vapor multicollector inductively coupled plasma mass spectrometry

This study presents a method for the isotope analysis of gaseous elemental mercury (GEM, He-(g)(0)) using cold vapor multicollector inductively coupled plasma mass spectrometry. Isotopic compositions of Hg in the atmospheric samples collected from urban-industrial (Ichikawa) and coastal (South Boso Peninsula) regions in Chiba, Japan were investigated. Values of mass-dependent fractionation (MDF) of delta Hg-202 range from -2.36%0 to -0.11%o and mass-independent fractionation (MIF) of Delta Hg-199 range between -0.31%o and 0.01%a. There was a rough linear correlation between delta Hg-202 values and Hg concentrations of our GEM samples (r(2) = 0.31, p < 0.05). Also, Delta Hg-199 values were positively correlated with SO2 concentrations; however, air mass source(s) was not identified using NOAA Hybrid Single-Particle lagrangian Integrated Trajectory model. We suggest that our sampling site, Ichikawa, was largely impacted by nearby anthropogenic sources (high GEM concentration with low delta Hg-202 value), and a mixing with back ground air (low GEM concentration with high delta Hg-202 value). (C) 2016 Elsevier B.V. All rights reserved.