ABSORPTION AND TOXICITY OF CHROMIUM AND CADMIUM IN LIMNANTHEMUM-CRISTATUM GRISEB

Limnanthemum cristatum Griseb. grows commonly in closed water bodies in India. Absorption of chromium and cadmium by this plant was determined in 3% Hoagland solution containing 0.05, 0.1, 1.0 and 2.0 ppm of these two metals. Treated leaves showed highest accumulation of chromium at 2 ppm after 168 h, however, concentration was greater in the root (960 mug/g dry wt.) than the leaf (620 mug/g dry wt.). In cadmium highest accumulation for the same duration was recorded at 0.1 ppm both in root (520 mug/g dry wt.) and leaf (515 mug/g dry wt.). Cadmium was found to be more toxic than chromium. Leaf and root decayed in a 1.0 ppm Cd solution within 48 h. On the other hand, chromium caused slight reduction in chlorophyll and almost no change in carotenoid. The possibility of using this plant for reducing chromium and cadmium levels in polluted waters is discussed.