ASSESSMENT OF HEAVY METALS AND MICROBIAL LOADS WITHIN THE COAL MINES OF ANAMBRA BASIN, NORTH CENTRAL, NIGERIA

The study aims to investigate the effect of coal mining on the drinking water quality of different water sources in Ankpa, Kogi State, Nigeria. A total of twenty (20) water samples were collected for physico-chemical (pH, Temperature, Electrical Conductivity, Total Dissolved Solids, turbidity, hardness), microbial (TPC, TC and E. coli) and heavy metal (Fe, Pb, Cr, Cu, As, Cd, Hg, Mn and Zn) analysis was determined using standard methods. The observed values of EC, TDS, chloride and sulphate were within WHO/NESREA standards. Heavy metals concentrations were generally low across the water sources. Similarly, the concentrations of Fe (0.01 – 0.18±0.048 mg/L), Pb (0.0006 – 0.008±0.002 mg/L), Cu (0.004 – 0.04±0.014 mg/L), Mn (0.003 – 0.032±0.0008 mg/L) and Zn (0.005 – 0.192±0.057 mg/L) were all within the permissible standards. The total coliform count of the water samples ranged from 1.40×102 to 2.00×102. The presence of E.coli in S-2, S-6, S-9, S-10, S-15 and S-19 is an indicator organism of feacal pollution. The heavy metal pollution index (HPI) was far less than (<100) the critical value of 100. The Hazard Index (HI) of the metals in water samples showed a low risk (HI<1) across the different age groups. While the cumulative Cancer Risk also shows extremely low risk for the analyzed metals and indicates no adverse effects on human health within the study area.