Results of monitoring for PCDDs and PCDFs in ambient air at McMurdo Station, Antarctica

摘要

This report presents the results of ambient air monitoring for polychlorinated dibenzo-p-dioxins (PCDDs) and polychlorinated dibenzofurans (PCDFs) performed during the 1992-1993 austral summer in the vicinity of McMurdo Station, Antarctica. Fifteen air samples were collected from four different locations for determination of the presence and concentration of PCDD/PCDF compounds. General Metal Works Inc. PS-1 air samplers equipped with polyurethane foam (PUF) with a sample flow rate of approximately 0.27 m(sup 3)/min. were used to collect air samples. Sampling site selection, sampling procedures, and quality assurance procedures used were consistent with U.S. Environmental Protection Agency guidance for local ambient air quality networks. PCDD/PCDF compounds were not detected at the predominantly upwind location and at a more remote site on Black Island. Trace levels of only a few PCDD/PCDF congeners were detected sporadically at a location approximately 500 meters downwind of the station. The most frequent, most varied, and highest levels of PCDDs/PCDFs were measured at a (open quotes)downtown(close quotes) location, where concentrations of total PCDDs ranged from 0.27 to 1.80 pg/m(sup 3) and total PCDFs from less than 0.1 to 2.77 pg/m(sup 3). Results from the remote Black Island site indicate that the background Antarctic air is still (open quotes)free(close quotes) of PCDD/PCDF compounds (not detectable at current method detection limits). The initial baseline effort demonstrated that site selection and sampling equipment performance were satisfactory, provided useful data for assessing the impact of McMurdo operations on the local ambient air quality, and provided baseline data for assessing the Antarctica continental air quality.