Determination of levels of trace metals in soils of kitchen gardens in the mining town of Lubumbashi and the risk of contamination of vegetable crops

Abstract

Objectives: in the city of Lubumbashi, the mining activity expansion has caused the contamination of the soils of the region with metallic trace elements (MTE) and the agricultural soils have not been spared. The vegetable crops sold in different markets have high levels of MTE. Methodology and results: This study was done in order to assess the level of contamination in the MTE cultivated garden soil and its impact on growth and bioaccumulation in vegetable crops. Thirty nine (39) composite soil sample were collected from 39 sites in the vegetable mining town of Lubumbashi and a trial was set up following a completely randomized experimental design with 4 replicates of 39 treatments (soil) using amaranth and spinach as test culture. Soil samples (before test) and plants (at harvest) were analyzed for Cu, Co, Pb, Cd and Zn. The results showed, first, that the garden soil had high levels of MTE and these high levels of MTE and lead to slower growth of vegetable crops and a high degree of bioaccumulation. Conclusion and potential application of the research: There is a risk of contamination of the food chain through the consumption of vegetable harvested in different sites of the mining town of Lubumbashi vegetables. The use of efficient and effective techniques of bioremediation of contaminated soils is important to reduce the risk of acute and / or chronic toxicity among consumers.

Keywords: contaminated soil, MTE, vegetable gardening, bioaccumulation, mining town of Lubumbashi

J. Appl. Biosci. 2013