Tranfers factor of radiocesium from fresh water environment into kyambang (Salvinia molesta) Available to Purchase

Tranfers factor of radiocesium from fresh water environment into kyambang (Salvinia molesta). Phytoremediation of radiocesium contaminated freshwater environment has been conducted. The study was conducted by examining ¹³⁴Cs uptake by kyambang (Salvinia molesta), another water plant i.e eceng gondok (Eichornia crassipes) had been studied before. Simulated freshwater ecosystem, i.e. a stainless steel tank filled with 400 L freshwater, was contaminated with 0,2 mL ¹³⁴CsCl of 4,84 x 10⁹ Bq/mL activity. Kyambang were put onto the tank and grown for about 40 days. As control, other kyambang were grown in another tank with uncontaminated water. Every five days, the water plants grown on contaminated and uncontaminated water, were sampled for measurement of ¹³⁴Cs uptake. At the same time 25 mL of water medium were also sampled to measure the concentration of ¹³⁴Cs. The water plant samples were separated into roots and non-roots (leaves with the stem), and then dried using infra-red lamp. The dried samples were put into plastic vials and destructed by adding HCl 5 M until the volume become 100 mL. The water plant and water samples each were measured using multi channel analyzer (MCA) with HPGe detector for 180 seconds. From this study, it was obtained that the kyambang can absorb and accumulate radiocesium from the medium. The ability of this plant to accumulate radiocesium was expressed as transfer factor, i.e. a ratio of ¹³⁴Cs concentration on the plant to that of on the water (the medium). From this study, relatively high transfer factor value of 5.9 mL/g was obtained with transfer rate coeficients of 3,077x10⁻⁷/day and 1,965x10⁻⁷/day for 0<t<25 and 29<t<40 respectively. The kyambang can be considered as a phytoremediator or depolluting agent of radiocesium in freshwater environment, although it is not economic.