HEAVY METAL POLLUTANTS AND MICROBIAL CONTAMINANT IN DRINKING WATER FROM WASH BOREHOLES IN PANTISAWA, YORRO L.G.A. OF TARABA STATE

Abstract

Borehole water remains a source of potable water in Nigeria. Therefore, regular monitoring of the safety of drinking water cannot be over-emphasized. Hence the need to study the safety of water in wash borehole from Pantisawa Yorro Local Government of Taraba State, Nigeria. A total of 15 samples from wash boreholes were randomly collected aseptically using sterilized bottles and igniting with a flame lighter on the surface of the water outlet from the five different zones (Pantisawa Main Market YM, Kapazang YG, Dola YD, Kallau YK and Zabi YZ) of Pantisawa. The pour plate technique was used to ascertain microbial load while trace metals in water samples were determined using Atomic Absorption Spectroscopy (AAS) PG-990. The total bacteria coliform count in the borehole water samples ranged between 1.00×10⁶ cfu/ml and 9.00×10⁵ cfu/ml which generally exceeded the World health organization (WHO) standard limit of 1.0 x 10² cfu/ml for water. The most prevalent or predominant bacteria is Staphylococcus aureus with 40% distribution occurrences from four sample sites (YG, YM, YD and YK). E.coli had a 20 % distribution while Bacillus spp, Enterococcus spp, Salmonella spp, Streptococcus spp, Staphylococcus and Shigella spp  showed low percent distribution. The trace metal analysis for the water revealed the absence of Pb in all the water samples analyzed, Zn, Fe, Mn and Cu were below the admissible limits for all the sites except for Fe in sites YG which fall above the standard. All other elements (Ni, Cd, As and Co) were above the threshold limit set by National Standard for Drinking Water Quality (NSDWQ) and the World Health Organization (WHO) respectively. Thus, the presence of pollutants and microbial contaminants may have serious health risks to the people using such water for drinking and other domestic activities.