title: The in vitro estrogenic activities of polyfluorinated iodine alkanes.
abstract: BACKGROUND
  Polyfluorinated iodine alkanes (PFIs) are important intermediates in the synthesis of organic fluoride products. Recently, PFIs have been detected in fluoropolymers as residual raw materials, as well as in the ambient environment.
  
  
  OBJECTIVE
  High production volumes and potential environmental releases of PFIs might become a concern, but the exposure risk and toxicity of these chemicals are still unclear. In this study, we investigated the potential estrogenic effects of PFIs.
  
  
  METHODS
  We studied the estrogenic effects of fluorinated iodine alkanes (FIAs), fluorinated telomer iodides (FTIs), and fluorinated diiodine alkanes (FDIAs) using the E-screen and MVLN assays and the evaluation of estrogen-responsive genes in MCF-7 cells.
  
  
  RESULTS
  FIAs have an iodine atom at one end of the perfluorinated carbon chain. 1-Iodoperfluorohexane (PFHxI) and 1-iodoperfluorooctane (PFOI) promoted the proliferation of MCF-7 cells, induced luciferase activity in MVLN cells, and up-regulated the expression of TFF1 and EGR3. In these assays, other FIAs gave negative responses. FDIAs have an iodine atom at each end of the perfluorinated carbon chain, and all the FDIAs showed estrogenic effects. The estrogenic potencies of FIAs and FDIAs correlate well with the carbon chain length of the chemicals. The optimum chain length for estrogenic effects is six carbons, and then eight and four carbons. All FTIs have a single iodine atom at the end of a partially fluorinated carbon chain. None of the FTIs showed estrogenic effects in the tests.
  
  
  CONCLUSIONS
  The estrogenic effects of PFIs are dependent on the structural features of iodine substitution and chain length. This research will be helpful in further understanding the estrogenic effects of perfluorinated compounds.
authors: State Key Laboratory of Environmental Chemistry and Ecotoxicology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, People's Republic of China.
authors: Chang
authors: C
authors: Wang
authors: Thanh
authors: T
authors: Wang
authors: Wei
authors: W
authors: Liu
authors: Ting
authors: T
authors: Ruan
authors: Qunfang
authors: Q
authors: Zhou
authors: Jiyan
authors: J
authors: Liu
authors: Aiqian
authors: A
authors: Zhang
authors: Bin
authors: B
authors: Zhao
authors: Guibin
authors: G
authors: Jiang
mesh_terms: D000473:Alkanes / Q000737:chemistry / Q000494:pharmacology*; D045744:Cell Line, Tumor; D049109:Cell Proliferation / Q000187:drug effects; D004785:Environmental Pollutants / Q000737:chemistry / Q000494:pharmacology*; D004967:Estrogens / Q000494:pharmacology*; D015870:Gene Expression / Q000187:drug effects*; D054879:Halogenation; D006801:Humans
chemical_list: D000473:Alkanes; D004785:Environmental Pollutants; D004967:Estrogens