BIOACCUMULATION OF HEAVY METALS THROUGH EARTHWORMS FROM WATER HYACINTH (Eichhornia crassifes Solm) CONTAMINATED VERMICOMPOST

The present study was undertaken for evaluation of possible bioaccumulation of heavy metals such as cadmium, copper, iron, manganese, nickel. Lead and zinc in the samples like control soil, experimental soil and body powder of different species of earthworms through vermicomposting. All these metals were detected after 90 days of vermicomposting using flame atomic absorption spectrophotometer. The results revealed that with little differences, all metal are present in the samples. It was further reported that metals like Cu, Mn, Ni and Zn are absorbed where as Cd and Pb are excreted by earthworms. Among the earthworm species tested, Eudrilus euginae was found to be good for bioaccumulation of heavy metals as compared to other two species viz., Pheretima posthuma and Eisenia foetida.