Atmospheric mercury in the vapor phase, and in fine and coarse particulate matter at Perch River, New York

Daily samples of size segregated atmospheric particulate matter (d(a) < 2.5 mu m, and 2.5 mu m < d(a) < 10 mu m), and vapor-phase mercury have been collected at five locations in upstate New York over a period of two years. Atmospheric concentrations were determined for mercury and, in the particulate matter, for up to 38 other elements by Instrumental Neutron Activation Analysis (INAA). At the Perch River sampling site, the average vapor-phase mercury concentration was 2.4 ng m(-3) with a seasonal pattern of higher winter and lower summer concentrations observed over both years of sampling. The average fine and coarse particulate concentrations were 0.058 and 0.025 ng m(-3), respectively. Concentrations for the particulate concentrations followed a log-normal frequency distribution with the most frequently occurring value for fine particulates being 0.012 ng m(-3) and for coarse particulates 0.009 ng m(-3). Episodic high concentrations of both fine and coarse particulate mercury indicate the impact of specific sources. No correlation was found among the three different types of samples on either an overall or daily basis. By applying factor analysis (FA) to the data and using known marker species for specific types of emissions, the sources of the particulate mercury were identified and their contributions estimated. Fine particulate mercury concentrations were primarily associated with regional sources in the midwestern U.S.A., with copper smelting, and with the combined influence of aluminum and precious metals processing. Coarse particulate mercury concentrations were principally related to local aluminum processing facilities. The source identification results of the FA were confirmed by examining back-projected, mixed-layer wind trajectories. From February 1993 through the end of the particulate sampling in September 1993 fine particulate mercury concentrations declined significantly possibly due to the installation of particulate controls at one or more of the copper smelters. (C) 1998 Elsevier Science Ltd. All rights reserved.