Seasonal variation in bacterial flora of the wastewater and soil in the vicinity of industrial area.

Environmental pollution is one of the major problems being faced today due to the advent of extensive industrialization. Heavy metals are the most important contaminants in wastewater that are present in abundance and are toxic. Heavy metal contents of sewage in the industrial estate of Aligarh (U.P.) have been determined by atomic absorption spectrophotometry. The analysis of samples collected from six different locations revealed significantly high levels of Fe, Zn, Cu, Cr and Ni. Certain bacteriological (Total bacterial count, Total coliform. Fecal coliform, and Fecal Streptococci) parameters of domestic and industrial sewage as well as soils were monitored from March 1990 to January 1993. Total bacterial count, total coliform, fecal coliform and fecal streptococci were found to be lowest in all the samples of industrial wastewater compared to those in domestic sewage and soil systems. The soil however, contained highest total culturable bacterial population. In view of the common practice of the application of sewage to agricultural land in the neighbouring area, the discharge of industrial wastewater without proper treatment into public sewers should be strictly prohibited.