Diurnal and Seasonal Variation of Atmospheric Particulate Matter and Trace Gases in Industrial Area of Delhi: A Study

The diurnal and seasonal variation of PM 10 , SO 2 , NO 2 , NH 3 and water-soluble compounds were studied in Naraina industrial area; Delhi from January to December, 2017. It was observed that annual average concentrations of PM 10, SO 2 , NO 2 , NH 3, SO 4 2− , NO 3 − , NH 4 + ,Na + , K + , Ca 2+ , Mg 2+ , Cl − and F − in the day time were 227 ± 91, 9 ± 5, 59 ± 22, 65 ± 15, 17.45 ± 5.14, 17.60 ± 4.94, 8.66 ± 2.94, 4.05 ± 1.08, 3.46 ± 0.91, 10.38 ± 4.48, 3.15 ± 0.99, 43.06 ± 5.20 and 0.50 ± 0.12 µg m −3 , respectively and night time were 320 ± 127, 14 ± 7, 82 ± 25, 83 ± 20, 22.64 ± 5.22, 21.66 ± 5.0, 11.81 ± 3.47, 3.29 ± 0.87, 3.02 ± 1.19, 7.55 ± 3.16, 2.49 ± 0.95, 31.86 ± 4.70 and 0.37 ± 0.12 µg m −3 , respectively. PM 10 and sometimes NO 2 concentrations exceeded the Indian National Ambient Air Quality Standards. SO 2 , and NH 3 concentrations were within the standard. The selected parameters varied from season to season. In the night time, selected parameters concentrations were high in comparison to day time might be due to formation of inorganic secondary particulate matters and low wind speed in the ambient air.