Trace elemental composition of atmospheric particulate at Bhilai in central-east India

The atmospheric concentration of the particulate trace elements and compounds: chloride, nitrate, sulphate, fluoride, arsenic, beryllium, cadmium, copper, iron, manganese, nickel, lead, titanium, vanadium, and zinc were determined at two sampling stations located at Bhilai, an urban industrial location. It is the first such study in this part of India. Sampling sites were free from near source effect; 24-h samples were collected once every week by a high volume sampler on a glass fibre filter. Particulates collected from May 1995 until April 1996 were extracted employing an automatic digestion system. An inductively coupled plasma spectrometer equipped with an ultrasonic nebuliser (ICP-OES-UN) was used for elemental analysis. Anions were determined by ion-chromatography. High concentrations have been obtained for many elements. Enrichment calculations show high enrichment of Zn, Pb, Cu, Cd, As, Be and Cl. Seasonal variation has been noticed and during the rainy season there was a significant lowering in the pollutant levels. Statistical analysis has been carried out to deduce the effect of meteorological and source effects. Close correlation between benzo[a]pyrene (BaP), benzo[ghi]perylene (BghiP), lead and vanadium levels shows the contribution of vehicular and industrial emissions and on the basis of a lower BaP/BghiP ratio the vehicular emission appears to be the major contributor of certain elements in the particulate. The levels of many elements are higher than the results obtained in various other parts of the world.