Seasonal variations of heavy metal concentrations in Qua Iboe River Estuary, Nigeria

Abstract

Concentrations of six heavy metals namely Pb, Ni, V, Fe, C and Cd were determined in water samples from Qua Iboe river estuary and its associated creeks for six months (January to June, 1999). Results obtained indicate the following mean concentrations for the metals: Pb, 0.167mg/1 + 0.148; Ni, 0.112mg/1 + 0.089; V, 0.019mg/1 + 0.042; Fe, 0.118mg/1 + 0.077; Cu, 0.020mg/1 + 0.026 and Cd, 0.036mg/1 + 0.036. These concentrations were higher in the wet season than the dry season. On comparing these results with the WHO standard, it was observed that the mean concentrations of Pb and Ni were higher than the acceptable limit while the coefficient of variations of the metals were correspondingly high with the high degree of fluctuations in their concentrations from station to station and from season to season. The location of the river estuary correlated positively with its observed high metal concentrations. The environmental implications of these metals are discussed with reference to existing water quality of the river.


KEY WORDS: Heavy metals, water sample, pollution, Qua Iboe River.


Global Jnl of Pure and Applied Sciences Vol.10(4) 2004: 611-617