Heavy metal depositions around some petroleum product depots in Nigeria using mosses as biomonitors

Abstract

This study was aimed at assessing atmospheric depositions of heavy metals around Nigerian NNPC depots using the moss (Barbula lambarenensis). Concentrations of 7 elements (Cd, Pb, Ni, Cu, Cr, Fe and Zn) were determined in the moss samples by Flame Atomic Absorption Spectrophotometry analysis. Nickel concentrations in the moss samples across the depots, except Mosimi NNPC depot were highest (p<0.05). A comparison of the metal depositions among the depots revealed that elemental contents of the mosses were significantly the same (p<0.01) in all the depots except for Cd and Cu in Ibadan and Mosimi NNPC depots respectively. This could be attributed to fact that Ibadan depot is situated close to residential areas with major input of Cd from domestic wastes incineration while Mosimi depot serves several other depots around it, so vehicular activities was greater and also the release of Cu. Generally, the pollution level of these depots is high and this calls for their proper monitoring to reduce workers exposure to heavy metal hazards.