Assessment of physiochemical, heavy metal and indicator bacterial groups in water and soil samples of different oil contaminated regions, Tiruchirappalli city

Abstract

The levels of physiochemical, heavy metal and microbiological pollution in different oil contaminated regions of Tiruchirappalli city were reported in the study. The water and sediment samples from four different oil contaminated regions in Tiruchirappalli city were collected during monsoon 2015. The sampling regions were divided into two category such as heavy oil contaminated regions (oil shed / oil washed regions) and bus stand regions. In oil contaminated water sample, the ranges of pH, TDS, EC, DO, BOD, COD, TA, TH, Ca, Mg, Na, K, HCO3, CO3, Cl, SO4, N-NO2, O-PO4 and oil-grease were 7.4-8.4, 395.4-651.4 mg/L, 670.2-1104.1 μS/cm, 0-1, 3.4-6.4, 5.5-76.9, 14.2-17.4, 74.5-165.4, 24.4-159.9, 16.0-81.5, 8.4-78.4, 24.5-66.3, 21.5-48.9, 86.7-161.4, 0 - 0, 79.5-145.2, 48.5-115.6, 2.3-15.2, 6.2-14.4 and 7.9-15.4 mg/L, respectively. But in soil sample, the ranges of Cd, Cr, Cu, Fe, Ne Pb and Zn were 0.14-0.65, 0.11-0.22, 0.19-0.52, 0.91-3.46, 0.1-0.2, 0.12-0.22, 0.65-1.82 mg/kg, respectively. In oil contaminated water sample, counts of TVC, TC, TS, FC, FS, VC, SAC, SHC and PC were in the range of 21300-126000, 1620-13200, 240-1050, 250-1130, 100-250, 120-180, 80-160, 130-200 and 260-560 CFU/mL, respectively. In soil sample, the TVC, TC, TS, FC, FS, VLO, SC and PC ranges were 56000-218000, 3100-14800, 350-1260, 330-1420, 150-300, 110-240, 120-200, 160-260 and 410-1060 CFU/g, respectively. The results of this study indicated that oil shed regions gor higher pollutions tha bus stand regions. This study gave a special emphasis on the determination of the levels of pollution and also identified the vulnerable regions. Hence, throughout impoundment and continuous monitoring is needed.