Persisting Effects in Daphnia magna Following an Acute Exposure to Flowback and Produced Waters from the Montney Formation

Abstract

Hydraulic fracturing extracts oil and gas through the injection of water and proppants into subterranean formations. These injected fluids mix with the host rock formation and return to the surface as a complex wastewater containing salts, metals, and organic compounds, termed flowback and produced water (FPW). Previous research indicates that FPW is toxic to Daphnia magna (D. magna), impairing reproduction, molting, and maturation time; however, recovery from FPW has not been extensively studied. Species unable to recover have drastic impacts on populations on the ecological scale; thus, this study sought to understand if recovery from an acute 48 h FPW exposure was possible in the freshwater invertebrate, D. magna by using a combination of physiological and molecular analyses. FPW (0.75%) reduced reproduction by 30% and survivorship to 32% compared to controls. System-level quantitative proteomic analyses demonstrate extensive perturbation of metabolism and protein transport in both 0.25 and 0.75% FPW treatments after a 48 h FPW exposure. Collectively, our data indicate that D. magna are unable to recover from acute 48 h exposures to ≥0.25% FPW, as evidence of toxicity persists for at least 19 days post-exposure. This study highlights the importance of considering persisting effects following FPW remediation when modeling potential spill scenarios.

Performance Evaluation of a High Salinity Produced Water Treatment Train: Chemical Analysis and Aryl Hydrocarbon Activation

“…10,11 Further studies have used Daphnia magna, such as those by Boyd et al, who investigated the toxicity of flowback water from the Montney Formation in Canada. 12 Azetsu-Scott et al, using Microtox tests, found that toxicity increased over time following discharge of PW from offshore oil production installations due to the precipitation of heavy metals present in PW. 13 Overall, there is a lack of research on the toxicity of treated PW.…”

“…Hull et al observed significant cytotoxicity in PW from the Denver-Julesburg basin in Colorado via bioluminescence over a 220-day period . McLaughlin et al studied the acute toxicity on Daphnia magna from a minimally treated PW discharged into a stream used for agriculture and livestock and found several chemicals above their MCL thresholds at the discharge site, including known carcinogens. , Further studies have used Daphnia magna , such as those by Boyd et al, who investigated the toxicity of flowback water from the Montney Formation in Canada . Azetsu-Scott et al, using Microtox tests, found that toxicity increased over time following discharge of PW from offshore oil production installations due to the precipitation of heavy metals present in PW .…”

Efficacy of Nanofiltration and Reverse Osmosis for the Treatment of Oil-Field Produced Water Intended for Beneficial Reuse

“…Further, the toxicity level of the treated produced water, which indicates potential ecological and health impacts, presents a significant risk but has rarely been discussed in the literature pertaining to produced water treatment. Indeed, the toxic effects of untreated produced water have been demonstrated for various organisms, ,,− rendering toxicity a key indicator for ensuring sufficient treatment.…”