title: Balancing the Budget: Accounting for Glucocorticoid Bioactivity and Fate during Water Treatment.
abstract: Numerous studies have identified the presence and bioactivity of glucocorticoid receptor (GR) active substances in water; however, the identification and activity-balance of GR compounds remained elusive. This study determined the occurrence and attenuation of GR bioactivity and closed the balance by determining those substances responsible. The observed in vitro GR activity ranged from 39 to 155 ng dexamethasone-equivalent/L (ng Dex-EQ/L) in the secondary effluents of four wastewater treatment plants. Monochromatic ultraviolet light of 80 mJ/cm(2) disinfection dose was efficient for GR activity photolysis, whereas chlorination could not appreciably attenuate the observed GR activity. Ozonation was effective only at relatively high dose (ozone/TOC 1:1). Microfiltration membranes were not efficient for GR activity attenuation; however, reverse osmosis removed GR activity to levels below the limits of detection. A high-sensitivity liquid chromatography with tandem mass spectrometry (LC-MS/MS) method was then developed to screen 27 GR agonists. Twelve were identified and quantified in effluents at summed concentrations of 9.6-21.2 ng/L. The summed Dex-EQ of individual compounds based on their measured concentrations was in excellent agreement with the Dex-EQ obtained from bioassay, which demonstrated that the detected glucocorticoids can entirely explain the observed GR bioactivity. Four synthetic glucocorticoids (triamcinolone acetonide, fluocinolone acetonide, clobetasol propionate, and fluticasone propionate) predominantly accounted for GR activity. These data represent the first known publication where a complete activity balance has been determined for GR agonists in an aquatic environment.
authors: University of Arizona , 1133 E. James E. Rogers Way, Harshbarger 108, Tucson, Arizona 85721-0011, United States.
authors: Ai
authors: A
authors: Jia
authors: University of Arizona , 1133 E. James E. Rogers Way, Harshbarger 108, Tucson, Arizona 85721-0011, United States.
authors: Shimin
authors: S
authors: Wu
authors: University of Arizona , 1133 E. James E. Rogers Way, Harshbarger 108, Tucson, Arizona 85721-0011, United States.
authors: Kevin D
authors: KD
authors: Daniels
authors: University of Arizona , 1133 E. James E. Rogers Way, Harshbarger 108, Tucson, Arizona 85721-0011, United States.
authors: Shane A
authors: SA
authors: Snyder
mesh_terms: D001681:Biological Assay / Q000379:methods*; D002853:Chromatography, Liquid; D005938:Glucocorticoids / Q000737:chemistry*; D010126:Ozone / Q000032:analysis; D011965:Receptors, Glucocorticoid / Q000737:chemistry* / Q000378:metabolism; D053719:Tandem Mass Spectrometry; D062065:Wastewater / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000737:chemistry*; D018508:Water Purification
chemical_list: D005938:Glucocorticoids; D010126:Ozone; D011965:Receptors, Glucocorticoid; D062065:Wastewater; D014874:Water Pollutants, Chemical