Assessment of Water Soluble Ionic Composition of Respirable Particulates from the Coastal Region, Gandhidham-Kachchh, Gujarat, India

Gaseous pollutants serve as precursors of ionic particles in the atmospheric environment, thus their control is necessitated along with the particulate with special reference to soluble ions. The present study was undertaken to assess the effect of Particulate Matter (PM10) associated Water-Soluble Ions (WSI) on the ambient air concentration. In total 134 airborne particulate matter (PM10) samples were collected from 11 stations from January to December in and around Gandhidham, Gujarat, India. Monthly sampling was carried out by the Respirable Dust Sampler (RDS) on 24 hr basis. The samples were subjected to chemical analyses for estimating water-soluble ions. The PM10 concentration in the analyzed samples ranged from 29 to 401 & mu;g/m(3). The amount of Na+, Ca2+ and K+ varied from 0.04 to 8.43 & mu;g/m(3), Below Detection Level (BDL) to 12.25 & mu;g/m(3), and 0.09 to 3.49 & mu;g/m(3), respectively following flame photometer method. The anions SO (2-), NO (-) and Cl- ranged from 0.31 to 3.68 & mu;g/m(3), 0.39 to 32.47 & mu;g/m(3), and 4.03 to 54.08 & mu;g/m(3), respectively. Higher concentrations were reported for all the ions during winter. From the results, it is evident that secondary anthropogenic aerosols, natural mineral aerosols and mixed sea salt contributed to higher ionic concentrations in the air.