Heavy Metal Levels in Waste Dumpsites and Risk Assessment of Cucumber (Cucumis sativus L.) Fruits Cultivated in Coastal Savannah.

Abstract

Cucumber cultivation on waste dumpsites in Ghana poses a potential health threat to the consuming public. This study assessed the levels of Fe, Cu, Hg, and Pb metals in both soil and cucumber fruits at harvest in pots under field conditions. Samples were collected from three active dumpsites and background soils at a depth of 0 - 30 cm. Metal levels in both cucumber and soils were determined before planting and at the harvest of matured cucumber fruits using a Niton XL3t GOLD field portable XRF (X-ray fluorescence spectrometer). The physicochemical properties of dumpsite soil were found to be at improved levels compared to the background soil. All studied metals were present in higher levels in dumpsite soil than in background soil. Specifically, Pomadze dumpsite soil exhibited elevated levels of Fe, Pb, and Hg that exceeded allowable limits, as did the cucumber fruits. Pollution indices including Igeo, EF, TR, and TF indicated contamination levels for Fe, Hg, and Pb in the following increasing order: New Winneba background soil < Oguakurom dumpsite soil < UEW South dumpsite soil < Pomadze dumpsite soil. To mitigate potential health risks from heavy metal accumulation, it is recommended that the Pomadze dumpsite be excavated and relocated to a designated landfill site at Nsuakyire.

Key words: Backyard farming, Cucumber fruit, Dumpsite soil, Soil Physichochemical, XRF, Pollution indices