PHYTOREMEDIATION OF SELECTED HEAVY METALS FROM AQUEOUS MEDIA BY WATER HYACINTH (EICHHORNIA CRASSIPES (Mart) Solms)

Abstract

Phytoremediation of heavy metals namely: Cadniium, Copper and Lead from aqueous medium by water hyacinth (Eichhornia crassipes(Mart) solms) was examined by growing the plants in aqueous media polluted with trace metals. The plants were harvested after 2 days of growth from three replicate treatments and an untreated control. The water hyacinth samples were separated into stems and leaves, air-dried, pulverised, digested and analysed for trace metals using Atomic Absorption Spectrophotometer. There was a appreciable accumulation of the three ions in the plant under study. The Cu2 + that accumulated in the leaves amounted to 1.89mg/kg relative to 1.06mg/kg in the stem, with accumulation factors of 0.189 and 0.106. Similarly, the quantity of Pb2 + accumulated in leaves of E.crassipes was 2.25mg/kg with accumulation factor 0.225 while 2.6mglkg with was found in the stem tissues with accumulation factor of 0.260. In the same vein, 0.61mg/kg of Cd II ions was accumulated in the leaves relative to 0.99mg/kg in the stem respectively with accumulation factor of 0.061 and 0.099. The study reveals that the effective remediating heavy metals Cu, Pb and Cd from aqueous medium using E.crassipes as a phytoremediator were in the order Pb > Cu > Cd. These results indicate that E.crassipes plant can be considered as possible phytoremediator of heavy metals to treats polluted water contaminated with cadmium, copper and lead. IV