title: Sublethal and Reproductive Effects of Acute and Chronic Exposure to Flowback and Produced Water from Hydraulic Fracturing on the Water Flea Daphnia magna.
abstract: Hydraulic fracturing is an industrial process allowing for the extraction of gas or oil. To fracture the rocks, a proprietary mix of chemicals is injected under high pressure, which later returns to the surface as flowback and produced water (FPW). FPW is a complex chemical mixture consisting of trace metals, organic compounds, and often, high levels of salts. FPW toxicity to the model freshwater crustacean Daphnia magna was characterized utilizing acute (48 h median lethal concentrations; LC50) and chronic (21 day) exposures. A decrease in reproduction was observed, with a mean value of 18.5 neonates produced per replicate over a 21 day chronic exposure to 0.04% FPW, which was a significant decrease from the average of 64 neonates produced in the controls. The time to first brood was delayed in the highest FPW (0.04%) treatment. Neonates exhibited an LC50of 0.19% of full-strength FPW, making them more sensitive than adults, which displayed an LC50value of 0.75%. Quantitative PCR highlighted significant changes in expression of genes encoding xenobiotic metabolism (cyp4) and moulting (cut). This study is the first to characterize chronic FPW toxicity and will help with the development of environmental monitoring and risk assessment of FPW spills.
authors.affiliation: Department of Biological Sciences, University of Alberta , Edmonton, Alberta T6G 2R3, Canada.
authors.forename: Tamzin A
authors.identifier: 0000-0001-6834-1571
authors.initials: TA
authors.lastname: Blewett
authors.affiliation: Department of Biological Sciences, University of Alberta , Edmonton, Alberta T6G 2R3, Canada.
authors.forename: Perrine L M
authors.initials: PL
authors.lastname: Delompré
authors.affiliation: Department of Biological Sciences, University of Alberta , Edmonton, Alberta T6G 2R3, Canada.
authors.forename: Yuhe
authors.initials: Y
authors.lastname: He
authors.affiliation: Department of Biological Sciences, University of Alberta , Edmonton, Alberta T6G 2R3, Canada.
authors.forename: Erik J
authors.initials: EJ
authors.lastname: Folkerts
authors.affiliation: Department of Earth and Atmospheric Sciences, University of Alberta , Edmonton, Alberta T6G 2R3, Canada.
authors.forename: Shannon L
authors.initials: SL
authors.lastname: Flynn
authors.affiliation: Department of Earth and Atmospheric Sciences, University of Alberta , Edmonton, Alberta T6G 2R3, Canada.
authors.forename: Daniel S
authors.initials: DS
authors.lastname: Alessi
authors.affiliation: Department of Biological Sciences, University of Alberta , Edmonton, Alberta T6G 2R3, Canada.|National Institute for Nanotechnology , 11421 Saskatchewan Drive, Edmonton, Alberta T6G 2M9, Canada.
authors.forename: Greg G
authors.identifier: 0000-0003-0786-8868
authors.initials: GG
authors.lastname: Goss
mesh_terms: D000818:Animals; D033361:Cladocera; D003621:Daphnia / Q000187:drug effects*; D000067071:Hydraulic Fracking; D012098:Reproduction / Q000187:drug effects; D014867:Water; D014874:Water Pollutants, Chemical / Q000633:toxicity
chemical_list: D014874:Water Pollutants, Chemical; D014867:Water