SPATIAL DISTRIBUTION AND VARIABILITY OF HEAVY METALS AND BACTERIAL CONTAMINATION IN SOIL AND WATER SAMPLES

ABSTRACT

Heavy metal and bacterial contamination are critical factors impacting environmental quality, especially in areas with vulnerable populations like primary and nursery schools. The present study investigated the spatial distribution and variability of heavy metals (Zn, Fe, Ni, Cu, Mn, Cd, Pb, Co, Cr) and microbial contamination in soil and water samples fromprimary andnurseryschools in the Southern Senatorial District of Edo State, comprising of Egor, Ikpobah-Okah, Oredo, Orhiomwon, Ovia North East, Ovia South West and Uhunmwonde. 15 schools weresampled from each of the local governments, a total of 105 samples were collected. Samples forheavy metals and bacterial were analyzed using standard methods. Coefficient of variation(CV)was used to assess the degree of variability in the concentrations of heavy metal. The result showed high levels of heavy metals (Cr and Cd) above the World Health Organization(WHO)limit in both water and soil samples in all the locations sampled. The mean values of heavymetals (15.72mg/l) recorded in Ovia North East for water samples and (37.065mg/kg) Ikpobah-Okha for soil samples had values that were significantly higher (P<0.05) compared withvaluesrecorded at Orhiomwon and Egor. Elevated microbial levels above the WHO recommendedlimit were noted across the different stations in both soil and water samples. The result for theCVindicates considerable levels of variability at the different local government sampled. Thehighest CV value for the heavy metal concentration at Ovia North East decreased in the order Co(1950%) > Mn (375%) > Ni (283.33%) > Cu (258.33%) > Cr (187.5%) > Zn (173.08%) > Fe (21.43%). The findings on this study provide information on the spatial distribution and variability of heavymetals and microbial contamination in soil and water samples from primary and nurseryschoolsin the Southern Senatorial District of Edo State.