Nigeria.

A general investigation of the groundwater quality of the Benin City Urban Aquifer of Benin Formation for the effects of athropogenic activities shows the following results: lead (Pb) has mean value of 0.044 mg/l from 25 sampled boreholes. Seven of these borehole waters show anomalous Pb values of over 0.050mg/l. For the 25 boreholes, Pb mean value of 0.044mg/l, 0.055mg/l standard deviation and variance of 0.003mg/l are indicative of high Pb concentration compared with 0.05mg/l W.H.O. limit.