title: Endocrine-disruption potential of perfluoroethylcyclohexane sulfonate (PFECHS) in chronically exposed Daphnia magna.
abstract: Perfluoroethylcyclohexane sulfonate (PFECHS), mainly used in hydraulic fluids in aircrafts, is a member of the perfluoroalkyl sulfonate family which includes the regulated perfluorooctane sulfonate (PFOS). PFECHS has been reported in environmental samples but its toxicity to aquatic organisms is unknown. The objectives of this study were to identify biological pathways altered by sublethal exposure (12 d) of D. magna to PFECHS (0.06, 0.6, and 6 mg/L) using microarray and quantitative real-time PCR and to identify potential biomarkers to link transcriptomic to phenotypic responses. PFECHS was also quantified in surface water samples (1.04-1.38 ng/L) collected from the St. Lawrence River, Canada. Transcriptomic analyses indicated the under-regulation of vitellogenin-related genes (VTG1) in PFECHS-exposed groups. PFECHS exposure also led to the up-regulation of genes related to cuticle. VTG was selected as a potential cellular marker and identified in D. magna using an immuno-specific assay and quantified using Western blot and LC/MS/MS. Results indicated a decrease of VTG content in exposed D. magna which was in concordance with the transcription of VTG-related genes. No effects were observed on survival, molting, or reproduction at the individual/population levels. Overall, results suggest endocrine disruption potential for PFECHS in D. magna at concentrations higher than levels reported in the aquatic environment.
authors.affiliation: Environment and Climate Change Canada, 105 McGill Street, Montreal, QC, H2Y 2E7, Canada. Electronic address: magali.houde@canada.ca.
authors.forename: Magali
authors.initials: M
authors.lastname: Houde
authors.affiliation: Environment and Climate Change Canada, 105 McGill Street, Montreal, QC, H2Y 2E7, Canada.
authors.forename: Mélanie
authors.initials: M
authors.lastname: Douville
authors.affiliation: Environment and Climate Change Canada, 105 McGill Street, Montreal, QC, H2Y 2E7, Canada.
authors.forename: Maeva
authors.initials: M
authors.lastname: Giraudo
authors.affiliation: Environment and Climate Change Canada, 105 McGill Street, Montreal, QC, H2Y 2E7, Canada.
authors.forename: Keven
authors.initials: K
authors.lastname: Jean
authors.affiliation: Environment and Climate Change Canada, 105 McGill Street, Montreal, QC, H2Y 2E7, Canada.
authors.forename: Mélanie
authors.initials: M
authors.lastname: Lépine
authors.affiliation: Environment and Climate Change Canada, 867 Lakeshore Road, Burlington, ON, L7S 1A1, Canada.
authors.forename: Christine
authors.initials: C
authors.lastname: Spencer
authors.affiliation: Environment and Climate Change Canada, 867 Lakeshore Road, Burlington, ON, L7S 1A1, Canada.
authors.forename: Amila O
authors.initials: AO
authors.lastname: De Silva
mesh_terms: D017738:Alkanesulfonic Acids / Q000032:analysis* / Q000633:toxicity; D000595:Amino Acid Sequence; D000818:Animals; D059001:Aquatic Organisms / Q000378:metabolism; D015415:Biomarkers / Q000032:analysis; D002170:Canada; D003621:Daphnia / Q000378:metabolism; D052244:Endocrine Disruptors / Q000032:analysis* / Q000633:toxicity; D005466:Fluorocarbons / Q000032:analysis* / Q000633:toxicity; D012098:Reproduction; D045483:Rivers / Q000737:chemistry; D013451:Sulfonic Acids / Q000032:analysis* / Q000633:toxicity; D053719:Tandem Mass Spectrometry; D015854:Up-Regulation; D014819:Vitellogenins / Q000235:genetics / Q000378:metabolism*; D014874:Water Pollutants, Chemical / Q000032:analysis* / Q000633:toxicity
chemical_list: D017738:Alkanesulfonic Acids; D015415:Biomarkers; D052244:Endocrine Disruptors; D005466:Fluorocarbons; D013451:Sulfonic Acids; D014819:Vitellogenins; D014874:Water Pollutants, Chemical; C569427:perfluoroethylcyclohexanesulfonic acid; C076994:perfluorooctane sulfonic acid
keywords: Endocrine-disruption; Freshwater invertebrates; Gene transcription; Perfluoroalkyl substances; Vitellogenin quantification