Energy producing companies require drilling fluids and additive oils for drilling, gas and lubricants that are essential for modern civilization and industrialization. Biological wastewater is conventionally treated for the elimination of organic and inorganic pollutants. In the fossil fuel industry, drill cuttings and fluids are the piled up wastes and an environmental hazard.

An attempt has been made to quantify the relative abundance and size distribution of oily-droplets in the ambient air of Shillong using an optical microscope. The sampling was carried out at controlled, moderate traffic, high traffic, traffic intersections, industrial estates and elevated specific locations in different seasons during 1998-2000.