title: Evidence for Different Reactive Hg Sources and Chemical Compounds at Adjacent Valley and High Elevation Locations.
abstract: The spatial distribution of chemical compounds and concentration of reactive mercury (RM), defined as the sum of gaseous oxidized mercury (GOM) and <3 μm particulate bound mercury (PBM), are poorly characterized. The objective of this study was to understand the chemistry, concentration, and spatial and temporal distribution of GOM at adjacent locations (12 km apart) with a difference in elevation of ∼1000 m. Atmospheric GOM measurements were made with passive and active samplers using membranes, and at one location, a Tekran mercury measurement system was used. The chemistry of GOM varied across time and location. On the basis of data collected, chemistry at the low elevation site adjacent to a highway was primarily influenced by pollutants generated by mobile sources (GOM = nitrogen and sulfur-based compounds), and the high elevation site (GOM = halogen-based compounds) was affected by long-range transport in the free troposphere over the marine boundary layer into Nevada. Data collected at these two locations demonstrate that different GOM compounds exist depending on the oxidants present in the air. Measurements of GOM made by the KCl denuder in the Tekran instrument located at the low elevation site were lower than that measured using membranes by 1.7-13 times. Accurate measurements of atmospheric concentrations and chemistry of RM are necessary for proper assessment of environmental impacts, and field measurements are essential for atmospheric models, which in turn influence policy decisions.
authors: Department of Natural Resources and Environmental Science and ‡Atmospheric Sciences Program, Department of Physics University of Nevada-Reno , Reno, Nevada 89557, United States.
authors: Mae
authors: M
authors: Sexauer Gustin
authors: Department of Natural Resources and Environmental Science and ‡Atmospheric Sciences Program, Department of Physics University of Nevada-Reno , Reno, Nevada 89557, United States.
authors: Ashley M
authors: AM
authors: Pierce
authors: Department of Natural Resources and Environmental Science and ‡Atmospheric Sciences Program, Department of Physics University of Nevada-Reno , Reno, Nevada 89557, United States.
authors: Jiaoyan
authors: J
authors: Huang
authors: Department of Natural Resources and Environmental Science and ‡Atmospheric Sciences Program, Department of Physics University of Nevada-Reno , Reno, Nevada 89557, United States.
authors: Matthieu B
authors: MB
authors: Miller
authors: Department of Natural Resources and Environmental Science and ‡Atmospheric Sciences Program, Department of Physics University of Nevada-Reno , Reno, Nevada 89557, United States.
authors: Heather A
authors: HA
authors: Holmes
authors: Department of Natural Resources and Environmental Science and ‡Atmospheric Sciences Program, Department of Physics University of Nevada-Reno , Reno, Nevada 89557, United States.
authors: S Marcela
authors: SM
authors: Loria-Salazar
mesh_terms: D000393:Air Pollutants; D001272:Atmosphere / Q000737:chemistry; D004784:Environmental Monitoring / Q000295:instrumentation*; D008628:Mercury; D017669:Mercury Compounds
chemical_list: D000393:Air Pollutants; D017669:Mercury Compounds; D008628:Mercury