title: Phytoremediation of Cr(III) by Ipomonea aquatica (water spinach) from water in the presence of EDTA and chloride: effects of Cr speciation.
abstract: Wastewater is often co-contaminated with chromium, chelating agents, and chloride. Influences of Cr(3+) speciation on Cr phytoremediation by Ipomonea aquatica were investigated. MINEQL+ was employed to estimate Cr speciation. Statistic regression was used to investigate the relationships between Cr speciation and accumulation. I. aquatica accumulated high Cr concentration (13,217 mg kg(-1)) in the root at Cr(3+) of 10 mg l(-1) and EDTA of 10(-4) M after 14 d growth. Pearson correlation analysis indicates that root Cr concentration significantly correlated with Cr-EDTA speciation (r = 0.67, p < 0.05) and Cr-Cl speciation (r = 0.91, p < 0.01). Shoot Cr concentration also significantly correlated with Cr-Cl speciation (r = 0.97, p < 0.01). An increase in Cl(-) concentration to 1.72 x 10(-4) M enhanced root Cr concentration; however, the accumulation of root Cr was inhibited at high Cl(-) concentration (5.76 x 10(-5) M). Microscopic image showed that a high portion of Cr(3+) accumulated on the root surface.
authors.affiliation: Department of Soil and Water Conservation, National Chung-Hsing University, Taichung 402, Taiwan, ROC.
authors.forename: Jung-Chun
authors.initials: JC
authors.lastname: Chen
authors.forename: Kai-Sung
authors.initials: KS
authors.lastname: Wang
authors.forename: Hsien
authors.initials: H
authors.lastname: Chen
authors.forename: Chi-Yuan
authors.initials: CY
authors.lastname: Lu
authors.forename: Lung-Chiu
authors.initials: LC
authors.lastname: Huang
authors.forename: Heng-Ching
authors.initials: HC
authors.lastname: Li
authors.forename: Tzu-Huan
authors.initials: TH
authors.lastname: Peng
authors.forename: Shih-Hsien
authors.initials: SH
authors.lastname: Chang
mesh_terms: D001673:Biodegradation, Environmental / Q000187:drug effects; D002712:Chlorides / Q000737:chemistry* / Q000494:pharmacology; D002857:Chromium / Q000737:chemistry* / Q000302:isolation & purification* / Q000633:toxicity; D004492:Edetic Acid / Q000737:chemistry* / Q000494:pharmacology; D027741:Ipomoea / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism*; D018517:Plant Roots / Q000187:drug effects / Q000254:growth & development / Q000378:metabolism; D012044:Regression Analysis; D012995:Solubility / Q000187:drug effects; D012996:Solutions; D014867:Water / Q000378:metabolism*
chemical_list: D002712:Chlorides; D012996:Solutions; D014867:Water; D002857:Chromium; D004492:Edetic Acid