ACCUMULATION OF ARSENIC BY AQUATIC PLANTS

Ten varieties of aquatic plants were collected from 22 pools resulting from tin-mining activities in and around Kuala Lumpur. The concentrations of arsenic in these plants partially reflected the concentrations of arsenic in pool water, which ranged from 0.002 to 0.25-mu-g ml-1. Uptake of arsenic by one of the aquatic plants, hydrilla, Hydrilla verticillata Casp., was studied in the laboratory. Results indicated that uptake was a function of initial arsenic concentration. In the presence of high phosphate concentrations, uptake of arsenic by Hydrilla verticillata was inhibited. Hydrilla verticillata can be used as a bioindicator of arsenic pollution in the aqueous ecosystem as it fulfilled the criteria for an indicator organism.