Threat of the Health Quality of Garden Produces Linked to Pollution by Toxic Metals on Some Gardening Sites of Benin

Abstract

Problem statement: Water and soil are vital resources used in agriculture. Current data establish a link between the pollution of soil, water and public health. For this reason, this study attempted to establish a link between the level of pollution of garden sites in lead (Pb), Cadmium (Cd) and Arsenic (As) and the health quality of vegetables grown there, through the quality of soil and of the irrigation water. Approach: Composite samples of vegetables, irrigation water and soil taken in the same periods at two garden sites in the city of Cotonou and another one in the village of Aplahoue, were analyzed for Pb, Cd and As by atomic absorption spectrophotometer. The amounts (average ± SD) have been compared by the statistical Student p test (T>t) = 0.05. Results: The results show that all the vegetables grown on the three sites are differently contaminated with Pb, Cd and As, as well as their irrigation water and the soil. However, the link attempted to be established between pollution of soil, irrigation water and quality of vegetables, could not be obvious, it has been discussed. Soil pollution with toxic metals seems to be of minor importance and does not directly influence the contamination of vegetables Conversely to soil pollution, the levels of contamination of irrigation water by trace metals (Cd and As) are much closer to that of vegetables, apart Pb. However, the high urban and atmospheric pressures in Cotonou have significantly influenced the contamination. For, it is in Aplahoue, farming environment, that the lowest amounts of metals in water and in the vegetables have been recorded. Conclusion/Recommendations: There is a risk of contamination in the food chain by heavy metals whose consumption through these gardening products could cause public health problems. Thus, the adoption of reasonable behavior and the development of new technologies are needed to associate food security, economic development, the preservation of the environment and public health.