Air Pollution over Rural West Bengal

Ambient air quality monitoring over 12 hour and 24 hour periods was monitored at 4-5 m above ground level for over two years (1978-1980) at five stations with varying degrees of urbanisation, viz. Debagram (Nadia district), Digha and Jhargram {Midnapur district), Jhalda (Purulia district) and Durgapur (Burdwan district) indicates annual mean level of SPM exceeding the standard annual mean (75 μg/m³) stipulated by the USEPA. The maximum permissible 24 hour value of 260 μg/m³ (after USEPA) is exceeded on about one-third of the days at Durgapur, Jhalda and Debagram and for 30-40 days in the year at Jhargram and Digha. Benzene-soluble organic matter constitutes a major part of the SPM at all the stations while poly-nuclcar aromatic hydrocarbons constitute upto 30% of the SPM. However, the levels of the gaseous pollutants viz. SO₂, NOx and total oxidants were well below the permissible limits.

Results of this study indicate that the "fallout" of the industrial plants of the Greater Calcutta and Asansol-Durgapur Belt is already causing a high incidence of air pollution all over the southern West Bengal in respect of SPM. Stringent measures to control industrial emissions as well as a massive planned programme of tree planting and appropriate soil conservation measures are recommended.