A study on trace elemental composition of atmospheric aerosols at a semi-arid urban site using ICP-MS technique

A study has been carried out on trace elemental composition of atmospheric aerosols (PM10) over a 1-year period i.e. from October 2001 to September 2002 at a semi-arid urban site, Tirupati, southern peninsular India. The samples were collected on paliflex filters with a frequency once a week using Mini-Partisol air sampler equipped with PM10 inlet. Aerosol loaded filters were extracted by the hot extraction method and the elemental concentrations were determined using inductively coupled plasma mass spectrometry (ICP-MS). Detection limits were found to be in a sub-ppt range and the precision about <5% RSD with comparable levels of accuracy. ICP-MS results are in good agreement with the certified data (<20% RSD). Elemental composition of PM10 showed a higher contribution of Fe followed by Mn and the lowest contribution of Be. Multivariate receptor model results (PC matrix) demonstrated that the trace elemental components of atmospheric aerosol were largely contributed from crustal material and road dust (69.41%), followed by metallurgical and other industrial processes (11.76%) and fuel oil combustion (6.52%). Regression models suggested the significant impact of meteorological factors on elemental concentration, which ranged between 14% and 53.6%. ANOVA results showed a clear trend of atmospheric levels of elements with variation in climatological conditions.