Distribution of metals in aquatic edible plants: Trapa natans (Roxb.) makino and ipomoea aquatica Forsk

Most of the water bodies being used for the cultivation of edible aquatic plants (Trapa natans and Ipomoea aquatica) in Lucknow district, U.P., India, were found to be contaminated with a variety of toxic metals (Fe, Cu, Cr, Mn and Pb). The concentration of metals Cr, Pb and Fe in water was much higher than recommended permissible limits of WHO (1995). The edible parts of these plants bioconcentrated metals from their surrounding water significantly. Therefore, the present study was planned to assess the metal concentration in edible part of plants which was collected from various water bodies used for cultivation of these crops. Despite varying levels of metals found in various fruit parts of T. natans, the metal accumulation in kernel was alarming. However, metal content decreased significantly in various parts after boiling the fruit. Similarly, I. aquatica also accumulated significantly higher amounts of these metals in leaves, however the metal accumulating potential varied considerably depending upon level of metal contamination in the water body in which they were growing. The importance of these findings in the exploitation of these aquatic crops to meet the demand of food and health perspectives for human beings is highlighted.