Composition and sources of fine particulate matter across urban and rural sites in the Midwestern United States

Abstract

The composition and sources of fine particulate matter (PM2.5) were investigated in rural and urban locations in Iowa, located in the agricultural and industrial Midwestern United States from April 2009 to December 2012. Major chemical contributors to PM2.5 mass were sulfate, nitrate, ammonium, and organic carbon. Non-parametric statistical analyses demonstrated that the two rural sites had significantly enhanced levels of crustal materials (Si, Al) driven by agricultural activities and unpaved roads. Meanwhile, the three urban areas had enhanced levels of secondary aerosol (nitrate, sulfate, and ammonium) and combustion (organic and elemental carbon). The heavily industrialized Davenport site had significantly higher levels of PM2.5 and trace metals (Fe, Pb, Zn), demonstrating the important local impact of industrial point sources on air quality. Sources of PM2.5 were evaluated by the multi-variant positive matrix factorization (PMF) source apportionment model. For each individual site, seven to nine factors were identified: secondary sulfate (accounting for 29–30% of PM2.5), secondary nitrate (17–24%), biomass burning (9–21%), gasoline combustion (6–16), diesel combustion (3–9%), dust (6–11%), industry (0.4–5%) and winter salt (2–6%). Source contributions demonstrated a clear urban enhancement in PM2.5 from gasoline engines (by a factor of 1.14) and diesel engines (by a factor of 2.3), which is significant due to the well-documented negative health impacts of vehicular emissions. This study presents the first source apportionment results from the state of Iowa and is broadly applicable to understanding the differences in anthropogenic and natural sources in the urban-rural continuum of particle air pollution.

Source Contribution of PM2.5 at Different Locations on the Malaysian Peninsula

“…Particulate matter with aerodynamic diameters less than 2.5 lm (PM 2.5 ) has been studied extensively as it is associated with air quality issues, particularly in urban areas (Huang et al 2013;Kundu and Stone 2014). PM 2.5 can easily penetrate into the respiratory organs of the human body which may lead to health problems and even mortality (Dockery et al 1993;Pope et al 2002).…”

Ubiquitous influence of wildfire emissions and secondary organic aerosol on summertime atmospheric aerosol in the forested Great Lakes region

“…Relatively few studies have chemically characterized atmospheric aerosols in the rural Great Lakes region of the United States (Sheesley et al, 2004;Kim et al, 2005Kim et al, , 2007Zhang et al, 2009;Jeong et al, 2011;Sjostedt et al, 2011;Kundu and Stone, 2014;Bullard et al, 2017). Except for the major metropolitan areas of Detroit (MI), Chicago (IL), Minneapolis (MN), and Milwaukee (WI), much of the land is characterized by rural agricultural areas and remote forests without significant anthropogenic emissions.…”

“…Studies across rural Illinois and Ohio found major atmospheric contributions from secondary sulfate, nitrate, and OC, consistent with aerosol aging during transport (Kim et al, 2005(Kim et al, , 2007Zhang et al, 2009), though these locations were much less forested than the more northern Great Lakes regions. Kundu and Stone (2014) measured composition and sources at rural locations in Iowa, identifying major PM mass contributions from biomass burning, combustion, and dust. Jeong et al (2011 identified contributions from SOA, elemental carbon, and dust in rural Harrow, Ontario, downwind of Detroit and Windsor.…”

Ubiquitous Influence of Wildfire Emissions and Secondary Organic Aerosol on Summertime Atmospheric Aerosol in the Forested Great Lakes Region

“…Relatively few studies have chemically characterized atmospheric aerosols in the rural Great Lakes region of the United States (Sheesley et al, 2004;Kim et al, 2005;Kim et al, 2007;Zhang et al, 20 2009;Jeong et al, 2011;Sjostedt et al, 2011;Kundu and Stone, 2014;Bullard et al, 2017). Except for the major metropolitan areas of Detroit (MI), Chicago (IL), Minneapolis (MN), and Milwaukee (WI), much of the land is characterized by rural agricultural areas and remote forests without significant anthropogenic emissions.…”

“…Studies across rural Illinois and Ohio found major atmospheric contributions from secondary sulfate, nitrate, and organic carbon, consistent with aerosol aging during transport (Kim et al, 2005;Kim et al, 2007; locations were much less forested than the more northern Great Lakes regions. Kundu and Stone (2014) measured composition and sources at rural locations in Iowa, identifying major PM mass contributions from biomass burning, combustion, and dust. Jeong et al (2011) and (Sjostedt et al, 2011) identified contributions from secondary organic aerosol, elemental carbon, and dust in rural Harrow, Ontario, downwind of Detroit and Windsor.…”