TITLE:
Nano-Phytotechnological Remediation of Endosulfan Using Zero Valent Iron Nanoparticles
AUTHORS:
Harikumar P. S. Pillai, Jesitha Kottekottil
KEYWORDS:
Endosulfan, Phytoremediation, Nano-Phytoremediation, Zerovalent Iron Nanoparticles
JOURNAL NAME:
Journal of Environmental Protection,
Vol.7 No.5,
April
22,
2016
ABSTRACT:
Endosulfan,
an organochlorine pesticide, is known for its toxicity and ability to
accumulate in the environment. In India endosulfan was banned only in 2011 and
hence toxic residues are still persistent in the environment. The abilities of
three plant species Chittaratha (Alpinia calcarata), Tulsi (Ocimum sanctum),
and Lemongrass (Cymbopogon citratus) to remove endosulfan from soil in the
absence and presence of zerovalent iron nanoparticles (nZVIs) (1000 mg/Kg of
soil), i.e., by phytoremediation and nano-phytoremediation, were determined.
Extracted soil samples from the experimental plot were analyzed using Gas
Chromatograph with Electron Capture Detector (GC-ECD) and final dehalogenated
product was confirmed by Mass Spectrometer (MS). A. calcarata had the best
efficiency compared to the other two plant species and the efficiency decreased
in the order A. calcarata > O. sanctum> C. citrates. The initial
endosulfan removal rate was high (82% was removed within 7 days) when nano
phytoremediation experiments were conducted with A. calcarata but then
gradually decreased, probably because the activity of nZVI decreased over time.
The nZVI endosulfan degradation mechanism appears to involve hydrogenolysis and
sequential dehalogenation which was confirmed by GC-MS analysis. Only small
amounts of endosulfan were accumulated in the plants because the added nZVIs
might have promoted the reductive dechlorination of endosulfan.