Application of nanoscale zero valent iron combined with Impatiens balsamina to remediation of e-waste contaminated soils

摘要

E-waste contamination is of major environmental concern on a world scale, with the rapid development of electric industry. The recycling and disposal methods of e-wastes remain rudimentary, and pose a serious environmental threat and have adverse influences on human health, because toxic pollutants such as polychlorinated biphenyls (PCBs), and heavy metals are released into the environment during crude recycling. Nano-phytoremediation is a combined technology between nanotechnology and phytotechnology for remediation of contaminated environments. This work was aimed to investigate the tolerance and accumulation characteristics of e-waste pollution, as well as the effect of nanoscale zero valent iron (nZVI) on their phytoremediation capacity. Results showed that nZVI could facilitate the growth of plants both under clean soil and the high pollution, with increased by 30.3% and 53.5% respectively. This may be attributed to the improvement of soil quality and adjustment of soil pH by nZVI. Especially, all the nZVI adding treatments had significantly higher PCBs accumulation efficiency compared with that without addition of nZVI, thus indicating nZVI-phytroremediation would be a very promising method in the future.