Overview of Heavy Metal Concentrations in Public Pipe Borne Water and Its Safety Implications for the Communities in Abuja Metropolis North-Central Nigeria

Abstract

Heavy Metals (HM) are relatively dense metal or metalloid noted for its potential toxicity in the environment and these metals appear in the World Health Organization List of Chemicals of public health concern. Long-term exposure to HMs have been linked to slowly progressing physical, muscular and neurological degenerative processes in human that mimic Alzheimer’s disease, Parkinson’s disease, muscular dystrophy, multiple sclerosis, liver and kidney failures as well as alterations in gene expressions. This study assessed the concentration of some HM in public water supply in Abuja Metropolis from 2015 to 2016 with the view to determining its overall percentage compliance with the WHO(2008) recommended limits for drinking water quality . The HMs selected were aluminum (Al), iron (Fe), copper (Cu), and zinc (Zn) and manganese (Mn). A representative water samples from the six locations within the study area were collected and analyzed according to the Standard Methods and Procedures. Sampling regime took place three (3) times in each sampling month from which the monthly and annual mean values were obtained and analyzed statistically. The result indicated the following mean concentrations Al (0.61±0.13mg/l), Fe (0.21±0.06mg/l), Pb (ND), Cr (ND), and Mn (0.03±0.03mg/l). The overall average percentage compliance WHO limits were Al (70.60%, Fe (85%), Pb (100%), Cr (100%) & Mn (91%) respectively. The results revealed that all the selected HMs concentration in the public drinking water within the period were within the WHO recommended aluminum concentration that was slightly above the recommended limit of 0.20mg/l. The study recommended for limit except a substitute of aluminum sulphate in public water treatment and also concluded that the selected HMs concentrations in the public water supply in Abuja Metropolis within the period were in compliance with the WHO quality for safe drinking water and therefore safe for human consumption. However, concern was raised for its aluminum level and possible health implications on long-term exposure particularly the aged population.