Heavy Metals Resistant Rotifers from a Chromium Contaminated Wastewater can Help in Environmental Clean-up

Rotifers, isolated from an industrial wastewater of tanneries showed tolerance against Cd 2+ (0.37 mg ml -1 ), Cr 6+ (2.6 mg ml -1 ), Pb 2+ (5.5 mg ml -1 ) and Cu 2+ (2.2 mg ml -1 ). Chromium, copper and cadmium processing capability of rotifers was assessed to examine the suitability of rotifers as bioremediator of industrial wastewater. Philodina roseola decreased 40% Cr 6+ , 67% Cu 2+ and 76% Cd 2+ from the medium each containing 10 µg ml -1 of the metal within two days of inoculation. At the end of 8 days of culturing, the decrease for Cr 6+ , Cu 2+ , and Cd 2+ in the metal containing medium was 88%, 77%, and 89%, respectively. The decline in concentration of Cr 6+ , Cu 2+ and Cd 2+ in metal containing media by Notommata copeus was 82%, 61% and 97%, respectively after two days of inoculation and 96%, 81% and 99% after 8 days. The resistance of rotifers against heavy metals and their uptake ability can be exploited for metal detoxification and environmental clean-up operations.