Source contribution modeling of probable source-types' emissions of particulate toxic trace elements near Knoxville, Tennessee : a screening method

Ambient atmospheric sampling is necessary to assess the level of pollution contributed by anthropogenic and natural sources. Emission source-types were determined from particulate matter ≥ 10 microns sample data collected in Knoxville, Tennessee for one year beginning in September, 1990. After surveying the sampled area for probable sources, emission source elemental composition profiles from an EPA emission source data base were selected for comparison with the elemental composition profiles from the particulate matter ≥ 10 micron samples data base. Source contribution modeling, a type of receptor modeling, was developed to screen emission sources where a weighting technique is applied to the emission sources and the resulting emission sources elemental composition composite profile is evaluated by normal distribution difference analysis. The annual average sample's range of maximum percent contribution from sources was 0.289 to 34.592 percent of the particulate matter ≥ 10 microns. This sample had four major contributors which were sulfate from sulfur dioxide emissions, wood burning sources, diesel fuel burning sources and soil particulate. Their annual maximum percent contributions were 37.191, 34.592, 22.753, and 8.118, respectively. The source-type with the highest maximum percent contribution for a single day was sulfate from sulfur dioxide emissions with 81.288 percent.