CONTAMINATION OF FOOD PLANTS WITH HEAVY METALS AND THEIR IMPACTS ON NUTRITIONAL VALUES
Loading...
Date
2010
Authors
Journal Title
Journal ISSN
Volume Title
Publisher
DEPARTMENT OF ENVIRONMENTAL SCIENCES
Abstract
Heavy metals are considered as global environmental pollutants that are present everywhere in the environment. Urbanization, high population growth, construction and development and high demand for food are the major factors resulting in discharge of heavy metals to environment which ultimately lead to food chain contamination. Vegetables are the main source of diet and contamination of these vital sources may severely affect human health. Toxic metals have both direct and indirect effects on human health, while the effect on nutritional parameters is one of the indirect effects of heavy metals contamination.
This research work is divided into different parts and several experiments were conducted to achieve the objectives. The first study was conducted to evaluate the effects of heavy metals (cadmium (Cd), lead (Pb) and Cd-Pb mix) on bioaccumulation of different nutrients. Three plant species including potato (Solanum tuberosum L.), tomato (lycopersicon esculentum) and lettuce (Lactuca sativa L.) were grown in pots containing soil contaminated with Cd, Pb and Cd-Pb mix at four different levels. The edible portions of each plant were analyzed for Cd, Pb and different macro- and micro- nutrients including protein, vitamin C, nitrogen (N), phosphorous (P), potassium (K), iron (Fe), manganese (Mn), calcium (Ca) and magnesium (Mg). Results indicated significant variations in selected elemental concentrations in all the three plants grown in different treatments. The projected daily dietary intake values of selected metals were significant (P<0.001) for Fe, Mn, Ca and Mg but not significant for protein, vitamin C, N and P. The elemental contribution to Recommended Dietary Allowance (RDA) was significant for Mn. Similarly, Fe and Mg also showed substantial contribution to RDA, while Ca, N, P, K, protein and vitamin C showed the minimal contribution for different age groups. This study suggests that vegetables cultivated on Cd and Pb contaminated soil may significantly affect their quality