Characteristics of particulate matter collected at an urban background site and a roadside site in Birmingham, United Kingdom

This study was conducted to investigate the compositional characteristics of particulate matter (PM) collected both at an urban background site (Elms Road observational site, EROS) and a roadside site (Bristol Road observational site, BROS). PM samples were collected at the receptor sites between March 28 and April 11, 2012. Observed parameters included water-soluble ions (Cl-, NO-3, SO42-, Na+, NH4+, K+, Mg-2(+), Ca-2(+)) and trace metals (V, Al, Cr, Mn, Fe, Zn, Cu, Sb, Ba, Pb). Results showed higher concentrations of NO3-, NH4+, Al and Fe at BROS than EROS regarding PM2.5; and Cl-, NO3-, Na+, K+ and Fe regarding PM2.5-10, indicating roadside increments. The ionic and metal components of PM2.5 at EROS constituted 44 and 7% of the total measured PM mass, respectively. The proportions of these species were 46 and 8% at BROS. For PM2.5-10, water-soluble ions and trace metal components represented 42 and 12% at EROS, and 56 and 11% at BROS.