A study on the concentrations of Escherichia coli in soil and water samples, and some physicochemical properties of water collected from the Karnafuly River estuary, Bangladesh

Abstract

This study examined the concentrations of Escherichia coli in soil and water samples, and some
physicochemical properties of water collected from the Karnafuly River estuary, Bangladesh during
March-June 2012. Among the water parameters, temperature was in the range 26.5 to 32°C, salinity
varied between 0 and 5 ppt, pH values ranged from 7.5 to 7.9 and dissolved oxygen (DO) was recorded
at concentrations of 2.28 to 2.91 mg/l. The average total E. coli were 26 cells/ml in water, but the
sediment contained 96.42 cells/g of E. coli. The population of E. coli was always higher in sediment than
those that occurred in water among all sampling stations. The growth of E. coli were positively
correlated (P < 0.01) with water temperature and negatively correlated with salinity, pH and DO. The data
on water quality parameters and occurrence of E. coli indicated that water of the Karnafuly estuary is
polluted and unhygienic for drinking, even impossible to use for washing purposes without any
treatment.