摘要:AbstractTotal concentration, speciation, sources and potential health problems of Pb, Cd, Cu, Fe and Ni in a dumpsite soil within Calabar Municipality were evaluated in this work. The influence of organic matter and pH of the studied dumpsite soil on metal availability was also assessed. Results obtained indicated that; mean concentration of all the metals were higher in studied dumpsite soil than in the Control and higher than their recommended limits for Nigerian soil as well. Metal speciation revealed that, Pb and Fe existed mainly in the reducible form; Cd occurred in acid extractable fraction, Cu in oxidisable form while Ni existed primarily in inert (residual) fraction. Pb and Cu originated primarily from anthropogenic source whereas, natural source contributed mostly to the existence other metals in studied soil. All the environmental models utilized confirmed that, the studied dumpsite soil has been highly contaminated by these metals. Principal component analysis identified impact of wastes and industrial/agricultural wastes as the two major factors affecting the studied soil. Cluster analysis recognized the parameters with similar chemical properties and common source. Metals assessed exhibited variable correlations among themselves, while soil organic matter and pH displayed both significant positive and negative influence on metal availability. Results obtained identified Pb as the element with high risk potential in the studied soil and children as the highly vulnerable class.
关键词:Soil pollution;Speciation;Metal pollution index;Calabar Municipality;Potential ecological risk index and non-carcinogenic risks