Removal of Lambda-Cyhalothrin by Water Hyacinth (Eichornia Crassipes)

The efficiency and primary mechanism of phytoremediation of contaminated water with lambda-cyhalothrin, a synthetic pyrethroid pesticide, by water hyacinth (Eichhornia crassipes) was investigated. Around 11 g water hyacinth (Eichhornia crassipes Solms) grown in 250 ml culture solution was used to study the mechanism and effect of the removal of lambda-cyhalothrin in the growth chamber with a 14-h day and 10-h night at 25 plusmn 1degC. 10 mg I^-1 ampicillin was used to minimize bacterial growth as sterile solution culture. The dissipation rate of 1 mg^-1 lambda-cyhalothrin in culture solution was 0.00869, 0.00756, 0.00190, and 0.00188 h^-1, for the planted, sterile planted, implanted, and sterile unplanted treatment, respectively, which implied that plant uptake and phytodegradation took up 63.06% and that of microbial degradation did 11.62% to the removal of lambda-cylothrin. The rate of the amount accumulated in plant to the dissipation amount of lambda-cyhalothrin produced by plant was 28.7-46.5% after 72 h of treatment, and the accumulated lambda-cyhalothrin in water hyacinth plant dissipated by 32~38% in shoot and 53~75% in root after 1 week of incubation in culture solutions without added lambda-cyhalothrin, suggesting that plant uptake and phytodegradation might be the main process.