Heavy-metal content of roadside gutter sediments in Ibadan, Nigeria

Roadside gutter sediments collected from 40 different sites in the City of Ibadan, Nigeria, were analysed for the metals Pb, Zn, Cu, Ni, Co, and Cd. The sites varied in traffic density, population density, and industrial activity. About a ten-fold elevation of the background level of Pb was observed around high traffic density and high population density sites in comparison with background control sites. The highest level of contamination of the sediments with Pb occurred around a battery factory. The levels of the other metals in the sediments at all the sites did not reveal any significant contamination, the levels being generally low and about the background values.