Mutagenic Atmospheric Aerosol Sources Apportioned by Receptor Modeling

摘要

During winter 1985 EPA collected air quality samples and data in residential locations in Albuquerque, NM and Raleigh, NC as part of its Integrated Air Cancer Project. Major objectives of the study were to evaluate new sampling, analysis and receptor modeling procedures and to apportion fine particle mass and mutagenic activity of the organic fraction of fine particles to appropriate sources. Samples were collected in the two cities for 12-hour periods beginning at 7:00 am and 7:00 pm. The schedule was followed to aid in resolving the organic and inorganic chemical species emitted from residential wood burning (normally a night time activity) and from mobile source emissions. Samples were analyzed for mutagenicity, organic carbon, 14C content and inorganic species. Data from these analyses served as input to a multi-linear regression (MLR) model that calculates the relative contribution of extractable particulate organic matter and mutagenic activity observed in these two cities. The 14C results were used to validate the MLR model. Even though the monitoring sites in these cities, were both selected and found to be heavily impacted by residential wood burning (83% & 94% of the organic aerosol mass due to wood burning), a proportionately larger % of the mutagenicity of the fine particles was attributed to mobile sources (25 and 37%).