Physical and Chemical Composition of Particulate Pollutants in an Urban Area of Cardiff, Wales

 The  issue  of  particulate  matter  (PM)  and  associated  health  and  environmental  problems  has  been subjected to extensive research in a number of countries. However, there are no recent studies concerning the physical and chemical properties of PM from urban Cardiff. Measurements  were  made  to  study  particulate  matter,  their  sources,  chemical  compositions, gaseous precursorsand their seasonal variations in urban Cardiff (latitude: 51° 28 ́ 59.47 ̈N and longitude: 03° 09 ́ 58.08 ̈W)  from  December  2009  to  November 2010. A  low  volume  air  sampler  for  PM10and  PM2.5particles,  and  real-time  air  samplers  for  TSP,  PM10,  PM2.5,  PM1, NO,  NO2, NOx,  SO2and  VOCs  were used during sampling. The collected ambient air suspended particles were analysed for seven major ions (Cl−, NO3−, SO42−, Ca²⁺, Mg²⁺, K⁺and Na⁺) and 12 elements (Na, Mg, Al, K, Ca, Cr, Fe, Ni, Cu, Zn, Cd and Pb) by using an ion chromatography and atomic absorption spectrometer respectively.Cl⁻, SO42−and NO3−were generally the major ions in fractions of PM10and PM2.5, while the elements Na, Mg, Ca, Al, K, and Fe were the most abundant elements. A good correlation was observed between PM10and PM2.5 indicating that PM10and PM2.5 contribute significantly to PM levels in urban Cardiff.Most of the ions and elements in both PM fractions were abundant in the winter season. Natural sources were the highest contributors followed by anthropogenic sources for the analysed elements in PM10and PM2.5.Enrichment  factor  (EF)  analysis  showed  the  enrichment  factor  was higher  in  PM10and  PM2.5elements such as Zn, Pb, Cu, Cr and Cd. The high enrichment factor of these elements in urban Cardiff suggested that the dominant sources for these elements were non-crustal. Real-time measurements of PM precursorgases  did  not  exceed  the  standard  concentrations  given  by  the  Air  Quality  Strategy  (AQS)  for  these pollutants.