Heavy Metal Pollution in Kingtom and Granville Dump Sites in Freetown, Sierra Leone

Abstract

The studies reported here were undertaken as part of a wider environmental study on the level of heavy metal pollution in the Kingdom and Granville dumpsites in Freetown. The use of the Kingtom and Grandville dumpsites to grow edible crops without checking the level of metal toxicity created concern to undertake such research with a view to ascertain a healthy environment for the growing of crops. Two sets of samples, one from each dumpsite, were taken for analysis. Soil, water, and plants (cassava and krain krain) were tested for Pb, Zn, Ni, and Co. The geological surveys tested physical parameters like pH, temperature, and electrical conductivity. The soil samples were collected at a depth of 10 cm by an auger, and water samples from up, middle, and down river/lagoon and plants of two widely grown varieties were analyzed using the principles of atomic absorption spectrophotometry. The levels of Pb, Zn, Ni, and Co obtained exceeded the recommended WHO permissible standards. The present study has been of short duration, but the data could serve as a baseline for more investigations that give a more complete picture of the seasonal patterns in the level of pollution of heavy metal in the Kingtom and Granville dumpsites. It will be helpful to the Ministry of Health and Sanitation to create policies or legislation on the use of these nearby streams, dump sites, and their immediate environments. It will also help the Ministry of Education to create mass pollution awareness in the school curriculum and society, and therefore, the researcher recommends that community people should prevent overloading, that is, sort for heavy and light debris, and ensure safe waste distribution management.