title: Degradation of ethinyl estradiol by nitrifying activated sludge.
abstract: Degradation of ethinyl estradiol (EE2) by nitrifying activated sludge was studied with micro-organisms grown in a reactor with feedback of sludge fed with only a mineral salts medium containing ammonium as the sole energy source. Ammonium was oxidised by this sludge at a rate of 50 mg NH4+ g(-1) DW h(-1). This activated sludge was also capable of degrading EE2 at a maximum rate of 1 microg g(-1) DW h(-1). Using sludge with an insignificant nitrifying capacity of 1 mg NH4+ g(-1) DW h(-1), no degradation of EE2 was detected. Oxidation of EE2 by nitrifying sludge resulted in the formation of hydrophilic compounds, which were not further identified. Most probably degradation by nitrifying sludge results in a loss of estrogenic activity, as hydroxylated derivatives of EE2 are known to have a substantially lower pharmacological activity than EE2.
authors.affiliation: NV Organon, Oss, The Netherlands.
authors.forename: J S
authors.initials: JS
authors.lastname: Vader
authors.forename: C G
authors.initials: CG
authors.lastname: van Ginkel
authors.forename: F M
authors.initials: FM
authors.lastname: Sperling
authors.forename: J
authors.initials: J
authors.lastname: de Jong
authors.forename: W
authors.initials: W
authors.lastname: de Boer
authors.forename: J S
authors.initials: JS
authors.lastname: de Graaf
authors.forename: M
authors.initials: M
authors.lastname: van der Most
authors.forename: P G
authors.initials: PG
authors.lastname: Stokman
mesh_terms: D045166:Estradiol Congeners / Q000378:metabolism*; D004997:Ethinyl Estradiol / Q000378:metabolism*; D009584:Nitrogen / Q000378:metabolism; D010084:Oxidation-Reduction; D012722:Sewage; D014865:Waste Disposal, Fluid / Q000379:methods
chemical_list: D045166:Estradiol Congeners; D012722:Sewage; D004997:Ethinyl Estradiol; D009584:Nitrogen