Vol. 2, Issue 3 (2018)
Potential contamination of basic and acidic anions in rainwater of urban environment: A case study of Varanasi District, Utter Pradesh, India
Author(s): Shishu Pal Singh, Shivraj Singh, Kedar Nath, Rajesh Kumar
Abstract: This study aimed to determine the amount and composition of anions fall with rainwater in urban areas in Varanasi during the south-west monsoon seasons has been studied. The collected rainwater samples have been analyzed for major anions [Cl-, SO4–, CO3-, HCO3 and SO4–], pH along with conductivity. The volume weighted pH of rainwater varied from 6.5 to 8.2 with a mean value of 7.1 which is neutral in nature. The range of anions composition in rainwater as follows: 0.20 to 0.70 meqL-1 of Cl-, 0.010 to 1.9 meqL-1 of SO4 -, 0.2 to 1.3 meqL-1 of CO3-, and 0.0 to 18 meqL-1 of CO3 2-, The overall order of anion content in rain water was observed as follows: HCO3- > CO3> Cl >SO42- thus, Basic anions content (CO32- and HCO3-) in rainwater of Varanasi was much higher than acidic anions content (Cl- and SO42- ). About 35% of rainwater samples were observed to be acidic due to high SO2. Ion. Major part of sulphate ion in rainwater was of anthropogenic origin, i.e. by the oxidation of sulphur dioxide emitted from burning of fossil fuels from Motor vehicles and industries.