title: Occurrence and In Vitro Bioactivity of Estrogen, Androgen, and Glucocorticoid Compounds in a Nationwide Screen of United States Stream Waters.
abstract: In vitro bioassays are sensitive, effect-based tools used to quantitatively screen for chemicals with nuclear receptor activity in environmental samples. We measured in vitro estrogen (ER), androgen (AR), and glucocorticoid receptor (GR) activity, along with a broad suite of chemical analytes, in streamwater from 35 well-characterized sites (3 reference and 32 impacted) across 24 states and Puerto Rico. ER agonism was the most frequently detected with nearly all sites (34/35) displaying activity (range, 0.054-116 ng E2Eq L-1). There was a strong linear relationship (r2= 0.917) between in vitro ER activity and concentrations of steroidal estrogens after correcting for the in vitro potency of each compound. AR agonism was detected in 5/35 samples (range, 1.6-4.8 ng DHTEq L-1) but concentrations of androgenic compounds were largely unable to account for the in vitro activity. Similarly, GR agonism was detected in 9/35 samples (range, 6.0-43 ng DexEq L-1); however, none of the recognized GR-active compounds on the target-chemical analyte list were detected. The utility of in vitro assays in water quality monitoring was evident from both the quantitative agreement between ER activity and estrogen concentrations, as well as the detection of AR and GR activity for which there were limited or no corresponding target-chemical detections to explain the bioactivity. Incorporation of in vitro bioassays as complements to chemical analyses in standard water quality monitoring efforts would allow for more complete assessment of the chemical mixtures present in many surface waters.
authors.affiliation: U.S. Environmental Protection Agency/National Health and Environmental Effects Research Laboratory/Toxicity Assessment Division , Research Triangle Park, North Carolina 27711 United States.
authors.forename: Justin M
authors.identifier: http://orcid.org/0000-0002-6622-5769
authors.initials: JM
authors.lastname: Conley
authors.affiliation: U.S. Environmental Protection Agency/National Health and Environmental Effects Research Laboratory/Toxicity Assessment Division , Research Triangle Park, North Carolina 27711 United States.
authors.forename: Nicola
authors.initials: N
authors.lastname: Evans
authors.affiliation: U.S. Environmental Protection Agency/National Health and Environmental Effects Research Laboratory/Toxicity Assessment Division , Research Triangle Park, North Carolina 27711 United States.
authors.forename: Mary C
authors.initials: MC
authors.lastname: Cardon
authors.affiliation: CB&I Federal Services , Cincinnati, Ohio 45212 United States.
authors.forename: Laura
authors.initials: L
authors.lastname: Rosenblum
authors.affiliation: U.S. Geological Survey/Leetown Science Center , Kearneysville, West Virginia 25430 United States.
authors.forename: Luke R
authors.initials: LR
authors.lastname: Iwanowicz
authors.affiliation: U.S. Environmental Protection Agency/National Health and Environmental Effects Research Laboratory/Toxicity Assessment Division , Research Triangle Park, North Carolina 27711 United States.
authors.forename: Phillip C
authors.initials: PC
authors.lastname: Hartig
authors.affiliation: U.S. Environmental Protection Agency/National Risk Management Research Laboratory/Water Supply and Water Resources Division , Cincinnati, Ohio 45220 United States.
authors.forename: Kathleen M
authors.initials: KM
authors.lastname: Schenck
authors.affiliation: U.S. Geological Survey/South Atlantic Water Science Center , Columbia, South Carolina 29210 United States.
authors.forename: Paul M
authors.identifier: http://orcid.org/0000-0001-7522-8606
authors.initials: PM
authors.lastname: Bradley
authors.affiliation: U.S. Environmental Protection Agency/National Health and Environmental Effects Research Laboratory/Toxicity Assessment Division , Research Triangle Park, North Carolina 27711 United States.
authors.forename: Vickie S
authors.identifier: http://orcid.org/0000-0003-1661-8481
authors.initials: VS
authors.lastname: Wilson
mesh_terms: D001681:Biological Assay; D004967:Estrogens; D005938:Glucocorticoids; D011960:Receptors, Estrogen / Q000378:metabolism; D045483:Rivers; D014481:United States; D014874:Water Pollutants, Chemical
chemical_list: D004967:Estrogens; D005938:Glucocorticoids; D011960:Receptors, Estrogen; D014874:Water Pollutants, Chemical