ASSESSMENT OF HEAVY METAL CONTAMINATION IN BOREHOLES AROUND MECHANIC WORKSHOPS IN UYO METROPOLIS, AKWA IBOM STATE, NIGERIA

Abstract

This study was aimed at determining heavy metal contamination in boreholes around mechanic workshops in Uyo Metropolis, Akwa Ibom State, Nigeria. Water samples were collected in sterilized sample bottles from three locations where mechanic workshops were located. The water samples were analyzed for the presence of some heavy metals like lead, cobalt, nicked and cadmium. Atomic Absorption spectroscopy and standard microbiology procedures were used to determine the physico-chemical and microbiological quality of sampled water. The result showed that physico-chemical parameters; PH ranged from (7.1-7.5). Others are TDs which was in the range of 250-440mg/l. The results also showed that the concentration of lead was found to be within WHO limit (Pb≤0.01ppm). The concentrations of Nickel and cadmium were also found to be within WHO limits (0.02ppm and 0.003ppm) for Ni and Cd respectively. However, the concentration of cobalt in the samples was high above WHO limit (≤0.1 ppm)in Coliform and E. coli test, all the samples revealed that total coliform and E. Coli values are in agreement with the NSDWQ, NAFDAC and WHO requirement value. It is therefore recommended that water from boreholes need to be treated further before consumption in order to get rid of contaminants; and also a survey of borehole sites should be conducted prior to drilling to prevent areas of potential hazard to ground water.