title: Bioconcentration, metabolism and neurotoxicity of the organophorous flame retardant 1,3-dichloro 2-propyl phosphate (TDCPP) to zebrafish.
abstract: Organophosphate flame retardants are ubiquitous environmental contaminants; however, knowledge is limited regarding their environmental health risks and toxicity. Here, we investigated the effects of acute and long-term exposure to tris(1,3-dichloro-2-propyl) phosphate (TDCPP) to the nervous system of zebrafish. Zebrafish embryos (2 h post-fertilization) were exposed to TDCPP (0-100 μg/L) for 6 months up until sexual maturation. Concentrations of TDCPP and its metabolic product (bis(1,3-dichloro-2-propyl) phosphate, BDCPP) were measured in the tissues of 5 day post-fertilization (dpf) larvae. There was no effect on locomotion, acetylcholinesterase activity, levels of the neurotransmitters dopamine and serotonin, and expression of mRNAs and proteins related to central nervous system development (e.g., myelin basic protein, α1-tubulin) in any exposure group. However, in adult fish, reductions of dopamine and serotonin levels were detected in the brains of females but not males. Downregulation of nervous system development genes was observed in both the male and female brain tissues. TDCPP concentrations were measured in adult fish tissues including the brain, and greater levels were detected in females. Our results showed that females are more sensitive to TDCPP stress than males in terms of TDCPP-induced neurotoxicity. We demonstrate that long-term exposure to lower concentrations of TDCPP in fish can lead to neurotoxicity.
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China; University of Chinese Academy of Sciences, Beijing 100049, China.
authors.forename: Qiangwei
authors.initials: Q
authors.lastname: Wang
authors.affiliation: State Key Laboratory in Marine Pollution; Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong SAR, China; Research Centre for the Oceans and Human Health, City University of Hong Kong, Shenzhen Research Institute Building, Shenzhen 518057, China; Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong SAR, China.
authors.forename: James Chung-Wah
authors.initials: JC
authors.lastname: Lam
authors.affiliation: State Key Laboratory in Marine Pollution; Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong SAR, China; Research Centre for the Oceans and Human Health, City University of Hong Kong, Shenzhen Research Institute Building, Shenzhen 518057, China; Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong SAR, China.
authors.forename: Yin-Chung
authors.initials: YC
authors.lastname: Man
authors.affiliation: State Key Laboratory in Marine Pollution; Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong SAR, China; Research Centre for the Oceans and Human Health, City University of Hong Kong, Shenzhen Research Institute Building, Shenzhen 518057, China; Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong SAR, China.
authors.forename: Nelson Lok-Shun
authors.initials: NL
authors.lastname: Lai
authors.affiliation: State Key Laboratory in Marine Pollution; Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong SAR, China; Research Centre for the Oceans and Human Health, City University of Hong Kong, Shenzhen Research Institute Building, Shenzhen 518057, China; Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong SAR, China.
authors.forename: Karen Ying
authors.initials: KY
authors.lastname: Kwok
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China.
authors.forename: Yong yong
authors.initials: Yy
authors.lastname: Guo
authors.affiliation: State Key Laboratory in Marine Pollution; Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong SAR, China; Research Centre for the Oceans and Human Health, City University of Hong Kong, Shenzhen Research Institute Building, Shenzhen 518057, China; Department of Biology and Chemistry, City University of Hong Kong, Kowloon, Hong Kong SAR, China.
authors.forename: Paul Kwan-Sing
authors.initials: PK
authors.lastname: Lam
authors.affiliation: State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, China. Electronic address: bszhou@ihb.ac.cn.
authors.forename: Bingsheng
authors.initials: B
authors.lastname: Zhou
mesh_terms: D000818:Animals; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D004625:Embryo, Nonmammalian / Q000737:chemistry / Q000187:drug effects / Q000378:metabolism; D004781:Environmental Exposure; D005260:Female; D005411:Flame Retardants / Q000032:analysis / Q000378:metabolism* / Q000633:toxicity*; D005786:Gene Expression Regulation / Q000187:drug effects; D008297:Male; D009420:Nervous System / Q000187:drug effects* / Q000378:metabolism; D009943:Organophosphorus Compounds / Q000032:analysis / Q000378:metabolism* / Q000633:toxicity*; D012333:RNA, Messenger / Q000235:genetics; D012737:Sex Factors; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000378:metabolism / Q000633:toxicity; D015027:Zebrafish / Q000196:embryology / Q000378:metabolism / Q000502:physiology*
chemical_list: D005411:Flame Retardants; D009943:Organophosphorus Compounds; D012333:RNA, Messenger; D014874:Water Pollutants, Chemical; C016805:tris(1,3-dichloro-2-propyl)phosphate
keywords: Bioconcentration and metabolism; Gender-specific toxicity; Neurotoxicity; TDCPP; Zebrafish