title: Effect of cations on the solubilization/deposition of triclosan in sediment-water-rhamnolipid system.
abstract: Cations had great influence on the self-assembly of rhamnolipid, which in turn affected the fate of triclosan. The migration of triclosan from sediment to water benefited its biodegradation but it could be transformed into more toxic compounds. To regulate the fate of triclosan and reduce environmental risks extremely, the effect of four common cations in surface water (Na(+)/K(+)/Ca(2+)/Mg(2+)) on the solubilization/deposition of triclosan in sediment-water-rhamnolipid system was investigated. The interaction among cations, triclosan and rhamnolipid was explored based on self-assembly of rhamnolipid and water solubility of triclosan in rhamnolipid solutions. Results showed that cations had little influence on the fate of triclosan in the absence of rhamnolipid. Cations, especially Ca(2+)/Mg(2+), reduced the critical micelle concentration, micellar size and zeta potential of rhamnolipid solutions. The changes in self-assembly of rhamnolipid with different cations led to the difference of residual rhamnolipid concentration in water, which was nearly invariant with 0.01 M Na(+)/K(+) while decreased significantly with 0.01 M Ca(2+)/Mg(2+). Consequently, water solubility of triclosan in rhamnolipid solutions increased with the addition of Na(+)/K(+) whereas decreased with Ca(2+)/Mg(2+). In sediment-water- rhamnolipid system, triclosan was slightly solubilized from sediment to water with Na(+)/K(+) while deposited in sediment with Ca(2+)/Mg(2+). These findings provided an alternative application of rhamnolipid for the remediation of triclosan-polluted sediment.
authors.affiliation: Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, School of Environment and Energy, South China University of Technology, Guangzhou, 510006, PR China.
authors.forename: Yuanbo
authors.initials: Y
authors.lastname: Chen
authors.affiliation: Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, School of Environment and Energy, South China University of Technology, Guangzhou, 510006, PR China. Electronic address: ppyyhu@scut.edu.cn.
authors.forename: Yongyou
authors.initials: Y
authors.lastname: Hu
authors.affiliation: Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, School of Environment and Energy, South China University of Technology, Guangzhou, 510006, PR China.
authors.forename: Qian
authors.initials: Q
authors.lastname: Guo
authors.affiliation: Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, School of Environment and Energy, South China University of Technology, Guangzhou, 510006, PR China.
authors.forename: Jia
authors.initials: J
authors.lastname: Yan
authors.affiliation: Ministry of Education Key Laboratory of Pollution Control and Ecological Remediation for Industrial Agglomeration Area, School of Environment and Energy, South China University of Technology, Guangzhou, 510006, PR China.
authors.forename: Wenjin
authors.initials: W
authors.lastname: Wu
mesh_terms: D001673:Biodegradation, Environmental; D002412:Cations; D019015:Geologic Sediments / Q000737:chemistry*; D006017:Glycolipids / Q000737:chemistry*; D008823:Micelles; D012995:Solubility; D012996:Solutions; D014260:Triclosan / Q000737:chemistry*; D014867:Water / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000737:chemistry*
chemical_list: D002412:Cations; D006017:Glycolipids; D008823:Micelles; D012996:Solutions; D014874:Water Pollutants, Chemical; C418382:rhamnolipid; D014867:Water; D014260:Triclosan
keywords: Cation; Deposition; Rhamnolipid; Solubilization; Triclosan