title: In vitro characterization of the effectiveness of enhanced sewage treatment processes to eliminate endocrine activity of hospital effluents.
abstract: Occurrence of pharmaceuticals in aquatic ecosystems is related to sewage effluents. Due to the possible adverse effects on wildlife and humans, degradation and removal of pharmaceuticals and their metabolites during wastewater treatment is an increasingly important task. The present study was part of a proof of concept study at a medium sized country hospital in western Germany that investigated efficiency of advanced treatment processes to remove toxic potencies from sewage. Specifically, the efficiency of treatment processes such as a membrane bioreactor (MBR) and ozonation to remove endocrine disruptive potentials was assessed. Estrogenic effects were characterized by use of two receptor-mediated in vitro transactivation assays, the Lyticase Yeast Estrogen Screen (LYES) and the Estrogen Receptor mediated Chemical Activated LUciferase gene eXpression (ER CALUX(®)). In addition, the H295R Steroidogenesis Assay (H295R) was utilized to detect potential disruption of steroidogenesis. Raw sewage contained measurable estrogen receptor (ER)-mediated potency as determined by use of the LYES (28.9 ± 8.6 ng/L, 0.33× concentration), which was reduced after treatment by MBR (2.3 ± 0.3 ng/L) and ozone (1.2 ± 0.4 ng/L). Results were confirmed by use of ER CALUX(®) which measured concentrations of estrogen equivalents (EEQs) of 0.2 ± 0.11 ng/L (MBR) and 0.01 ± 0.02 ng/L (ozonation). In contrast, treatment with ozone resulted in greater production of estradiol and aromatase activity at 3× and greater concentrations in H295R cells. It is hypothesized that this is partly due to formation of active oxidized products during ozonation. Substance-specific analyses demonstrated efficient removal of most of the measured compounds by ozonation. A comparison of the ER-mediated responses measured by use of the LYES and ER CALUX(®) with those from the chemical analysis using a mass-balance approach revealed estrone (E1) to be the main compound that caused the estrogenic effects. Overall, treatment of sewage by use of MBR successfully reduced estrogenicity of hospital effluents as well as substances that are able to alter sex steroid production. However, after ozonation, effluents should undergo further investigations regarding the formation of endocrine active metabolites. The results obtained as part of this study demonstrated applicability of in vitro assays for monitoring of endocrine-modulating potency of treated sewage.
authors.affiliation: RWTH Aachen University, Institute for Environmental Research, Department of Ecosystem Analysis, Worringer Weg 1, 52074 Aachen, Germany.
authors.forename: Sibylle
authors.initials: S
authors.lastname: Maletz
authors.forename: Tilman
authors.initials: T
authors.lastname: Floehr
authors.forename: Silvio
authors.initials: S
authors.lastname: Beier
authors.forename: Claudia
authors.initials: C
authors.lastname: Klümper
authors.forename: Abraham
authors.initials: A
authors.lastname: Brouwer
authors.forename: Peter
authors.initials: P
authors.lastname: Behnisch
authors.forename: Eric
authors.initials: E
authors.lastname: Higley
authors.forename: John P
authors.initials: JP
authors.lastname: Giesy
authors.forename: Markus
authors.initials: M
authors.lastname: Hecker
authors.forename: Wilhelm
authors.initials: W
authors.lastname: Gebhardt
authors.forename: Volker
authors.initials: V
authors.lastname: Linnemann
authors.forename: Johannes
authors.initials: J
authors.lastname: Pinnekamp
authors.forename: Henner
authors.initials: H
authors.lastname: Hollert
mesh_terms: D019149:Bioreactors; D052244:Endocrine Disruptors / Q000737:chemistry* / Q000633:toxicity; D006761:Hospitals; D017744:Medical Waste Disposal / Q000379:methods*; D010126:Ozone / Q000737:chemistry*; D011960:Receptors, Estrogen / Q000378:metabolism; D012722:Sewage / Q000032:analysis; D018675:Toxicity Tests / Q000379:methods*; D014865:Waste Disposal, Fluid / Q000295:instrumentation / Q000379:methods*; D015003:Yeasts / Q000235:genetics
chemical_list: D052244:Endocrine Disruptors; D017744:Medical Waste Disposal; D011960:Receptors, Estrogen; D012722:Sewage; D010126:Ozone