Occurrence and Fate of Estrone, 17β-estradiol and 17α-ethynylestradiol in STPs for Domestic Wastewater

Abstract

Estrone (E1), 17b-estradiol (E2) and 17a-ethynylestradiol (EE2) discharged from sewage treatment plants (STPs) into surface waters, are seen as a threat effecting aquatic life by its estrogenic character. Therefore, much research is conducted on the fate and removal of these compounds. Since these compounds are present in influents and effluents in the ng/l range, methods for detection deserve special attention. Most important processes that play a role in the removal of estrogens are: adsorption, aerobic degradation, anaerobic degradation, anoxic biodegradation and photolytic degradation. Halflifes tend to vary and are remarkably shorter when low initial concentrations are applied. In general anaerobic conditions result in longer halflifes then aerobic conditions. EE2 shows far most persistence of the compounds, thereby also the estrogenic effect in vitro is about 2-3-fold higher compared to E2. The three compounds show a higher affinity to sorb to sludge compared to other tested adsorption materials like sediment. Aerobic degradation is far the most efficient in removing these compounds, but adsorption seems to play a significant role in retaining the estrogens inside full-scale STPs. Removal rates in full scale plants depend on the HRT, SRT and loading rates, but lack of information on the exact dependency so far prevents an optimal design able to fully eliminate estrogens from wastewater.

How are pharmaceutical and personal care products (PPCPs) removed from urban wastewaters?

“…Concerning hormones, the reported removal efficiencies of E1, E2 and EE2 vary strongly between studies. Different behaviors have been observed: (i) an increase along the passage of the STP (Baronti et al 2000;Carballa et al 2004); (ii) no significant removal (Ternes et al 1999a); and (iii) efficiencies higher than 80% (Ternes et al 1999b;de Mes et al 2005;Nakada et al 2006). Although it is not fully elucidated which factors could explain these deviations, since in many cases there are not enough operational data reported, some observations can be made: (i) different temperature of operation, as occurs between Brazilian and German STPs (Ternes et al 1999b); (ii) different kinetic behavior (k biol in Table 2), since E2 is almost completely oxidized to E1 in less than 3 h, the further oxidation of E1 is slower (50% after 24 h) and EE2 is not appreciable removed even after 48 h (Ternes et al 1999a).…”

17α‐Ethinylestradiol: An endocrine disrupter of great concern. Analytical methods and removal processes applied to water purification. A review

“…Auriol et al [82] reviewed EDCs removal at each step of water purification. First, EE2 undergoes physical removal by adsorption on particles [83]. For instance, in activated sludge process, between 60% and 80% of EE2 were shown to be adsorbed on sludge and thus eliminated from the aqueous phase [48,84,85].…”

Nonylphenol mass transfer from field-aged sediments and subsequent biodegradation in reactors mimicking different river conditions

“…Therefore, storage and natural attenuation (naturally occurring biodegradation) of these halogenated compounds in anaerobic sediments can reduce their bioavailability and concentration, respectively. Many non-halogenated hydrophobic organic pollutants, like poly aromatic hydrocarbons, petroleum hydrocarbons and natural hormones are less or nonbiodegradable under anoxic conditions (de Mes et al 2005;Vermeulen et al 2003). Storage of these non-halogenated organic compounds in anaerobic sediments slows down or even stops their biodegradation, thus creating a long-lasting potential source of pollution for the aquatic ecosystem in the future.…”