Comparative studies of chemical composition of particulate matter between sea and remote location of eastern part of India

Suspended particulate matter (SPM) was collected by using high volume samplers (HVS) from two different locations: Bay of Bengal (BoB) and State Botanical Garden (SBG) situated in the eastern part of India. The SPM samples were collected on Whatman No.41 filter papers. The samples were simultaneously collected daily from both the locations during March 17–April 1, 2006. The average SPM concentration over BoB and SBG was found to be 39.05 and 78.14 μg/m3 respectively. Na+ and SO42− were the most dominant water-soluble constituents over BoB and SBG respectively. The ratio of SO42−/NO3− concentrations in both the cases was observed to be > 1 indicating that the contribution of atmospheric acidity was more due to SO42− than NO3−. From intra-correlation analysis it is found that at both the locations, Na+ and Cl− were well correlated while SO42−-Ca2+ and SO42−-NH4+ were poorly correlated indicating the later ion pairs to be derived from different sources. The Windrose diagrams for wind speed and direction show that for SBG, the wind blew from the SE and SW directions and brought in pollutants from soil and anthropogenic sources. In case of BoB, the wind parcels mostly were blown from the land mass (EES direction) showing the influence of anthropogenic pollutants on the marine aerosols. All the variables can be classified into three factors using principal component analyses technique. It explained 85% of total variance.

Research Highlights
► The higher concentration of SPM at SBG indicates predominance of anthropogenic activities.
► Na+ and SO42– were the most dominant water-soluble constituents over BoB and SBG respectively.
► The SO42–/NO3– ratio indicating that the contribution of atmospheric acidity was more due to SO42– than NO3–.
► Windrose diagrams show that pollutants at SBG is from SE & SW directions and is anthropogenic origin.
► Windrose diagrams show the influence of anthropogenic pollutants on the marine aerosols at BoB.