title: Fe(III) and Fe(II) induced photodegradation of nonylphenol polyethoxylate (NPEO) oligomer in aqueous solution and toxicity evaluation of the irradiated solution.
abstract: Photodegradation of nonylphenol tri-ethoxylate (NPEO3) in aqueous solution, and the effects of Fe(III) or Fe(II) were studied. The increasing degradation kinetics of NPEO3were observed when 500µM Fe(III) or Fe(II) was present in the solutions. Altered formation of NPEO oligomers with shorter EO chains, including nonyphenol (NP), NPEO1and NPEO2, was observed in water and in solutions containing Fe(III) or Fe(II). The molar percentage yields of NP and NPEO1,2production from NPEO3photodegradation were approximately 20% in NPEO3solution, while NPEO3solution with Fe(III), this percentage increased to approximately 50%. In solution with Fe(II), the molar balance between the photodegradation of NPEO3and the production of NP and NPEO1,2was observed. A luminescent bacterium, Vibrio fischeri, was used to identify changes in the toxicity of NPEO3solutions during the photodegradation process under different conditions, while dose addition (DA) model was used to estimate the toxicity of products. Toxicity of NPEO3/water solution increased significantly following the irradiation of UVA/UVB mixture. In contrast, obviously decreasing toxicity was observed when NPEO3underwent photodegradation in the presence of Fe(III).
authors.affiliation: Ministry of Education Key Laboratory of Pollution Processes and Environmental Criteria/Tianjin Key Laboratory of Environmental Remediation and Pollution Control, Nankai University, Tianjin 300071, China. Electronic address: wang2007@nankai.edu.cn.
authors.forename: Lei
authors.initials: L
authors.lastname: Wang
authors.affiliation: Ministry of Education Key Laboratory of Pollution Processes and Environmental Criteria/Tianjin Key Laboratory of Environmental Remediation and Pollution Control, Nankai University, Tianjin 300071, China.
authors.forename: Junjie
authors.initials: J
authors.lastname: Zhang
authors.affiliation: School of Environmental Science and Safety Engineering, Tianjin University of Technology, Tianjin 300384, China.
authors.forename: Zhenghua
authors.initials: Z
authors.lastname: Duan
authors.affiliation: Ministry of Education Key Laboratory of Pollution Processes and Environmental Criteria/Tianjin Key Laboratory of Environmental Remediation and Pollution Control, Nankai University, Tianjin 300071, China.
authors.forename: Hongwen
authors.initials: H
authors.lastname: Sun
mesh_terms: D048908:Aliivibrio fischeri / Q000187:drug effects; D005026:Ethylene Glycols / Q000032:analysis* / Q000528:radiation effects / Q000633:toxicity; D005290:Ferric Compounds / Q000737:chemistry*; D005296:Ferrous Compounds / Q000737:chemistry*; D007700:Kinetics; D008962:Models, Theoretical; D010782:Photolysis; D012996:Solutions; D018675:Toxicity Tests; D014466:Ultraviolet Rays; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000528:radiation effects / Q000633:toxicity; D018508:Water Purification / Q000379:methods
chemical_list: D005026:Ethylene Glycols; D005290:Ferric Compounds; D005296:Ferrous Compounds; D012996:Solutions; D014874:Water Pollutants, Chemical; C021754:terics
keywords: Degradation pathways; Ferric/ferrous iron (Fe(III)/Fe(II)); Nonylphenol polyethoxylate (NPEO) oligomer; Photodegradation; Toxicity to luminescent bacteria