Lead and Cadmium Contents in Ipomoea aquatica Forsk. Grown in Laguna de Bay
Ipomoea aquatica Forsk. (water spinach) which grows luxuriantly in Laguna de Bay may contain metals that are within the toxic levels for humans. This study was conducted to determine the concentrations of lead (Pb) and cadmium (Cd) in the top, middle, and bottom of the edible portions, and in the different organs of I. aquatica grown in Laguna de Bay. Also, to assess if the Pb and Cd concentrations in the plants are within the safe levels for humans. Pb concentrations in the plants were 0.259 to 8.72 mg/kg DW, with decreasing trend from roots to leaves, and from bottom to top subsections of the upper 36cm from the shoot apex. Water spinach had Cd concentrations which were 0.0058 to 0.0466 mg/kg DW. Pb and Cd concentrations in the edible portions ( leaves and stems) of the upper 36cm of the shoot were far below the maximum tolerable daily intake for man set by World Health Organization (WHO). The bottom of the edible portion of the plant should be removed to minimize Pb intake.
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www.ilec.or.jp/eg/lbmi/reports/15_Laguna_de_Bay_ 27February2006
