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17a-ethynyl estradiol

Treatment Processes
Fate and Transport
CAS Number: 57-63-6
Synonyms: EE2
Contaminant Type: Chemical

17a-ethynyl estradiol is a synthetic chemical that is an ovulation inhibitor. It is a principal component in the oral contraceptive pill, is used in hormone replacement therapy, and is a prescription pharmaceutical product. In the technical literature it is oftentimes referred to as EE2.

It is an endocrine disrupting compound (EDC) with potential adverse effects in humans, animals and fish. [578] It is termed an estrogenic compound as it can block or mimic natural estrogen. It is one of the most potent estrogenic compounds. [578, 579] Links exist between EDCs like EE2 and reproductive failures and abnormalities in fish. [578] Concentrations as low as 2 ng/L could induce measurable changes in fish reproduction, and such concentrations are typical of those effluent from municipal waste water treatment plants. [578]

Residuals of EE2 passing the body are not completely removed during municipal waste water treatment and carry over into receiving streams that may serve as sources for drinking water treatment. [579]

EE2 is not regulated by USEPA in drinking water.  It is on Contaminat Candidate List 3.

The analytical methods for EE2 are varied, as are their detection levels. A study of European waste water effluents reported a mean of 1.4 ng/L and a maximum of 8.9 ng/L. [579] A study of four municipal waste water treatment effluents in the US reported an EE2 range 0.14 to 2.0 ng/L. [580] A study of European surface waters reported a mean of 0.8 ng/L and a maximum of 5.1 ng/L. [579] In surface waters in the Netherlands, EE2 was detected at three of 11 locations with detects in the 0.3 to 4.3 ng/L range. [581] It was not detected at 0.05 ng/L in two US surface waters. [580] In a survey of pharmaceuticals in US streams by the USGS, EE2 had a 5.7 percent frequency of detection with a median of 0.094 ug/L and a maximum of 0.237 ug/L. The USGS study was biased toward streams susceptible to contamination. [582, 583]

Date of Literature Search: March 2007

578 Snyder, S., Westerhoff, P., Yoon, Y. and Sedlak, D.; 2003; Pharmaceuticals, personal care products, and endocrine disruptors: implications for the water industry; Envir. Engrg. Sci.; 20:5:449
579 Kuck, H. and Ballschmitter, K.; 2001; Determination of endocrine disrupting phenolic compounds and estrogens in surface and drinking water by HRGC-(NCI)-MS in the picogram per liter range; Env. Sci. & Tech.; 35:15:3201
580 Huang, C. and Sedlak, D.; 2001; Analysis of estrogenic hormones in municipal wastewater effluent and surface water using enzyme-linked immunosorbent assay and gas chromatography/tandem mass spectrometry; Environ. Toxicol. & Chem.; 20:1:133
581 Belfoid, A., Van der Horst, A., Vethaak, A., Schafer, A., Rijs, G., Wegener, J. and Cofino, W.; 1999; Analysis and occurrence of estrogenic hormones and their glucuronides in surface water and waste water in the Netherlands; Sci. of the Total Envir.; 225:1-2:101
582 Kolpin, D., Furlong, E., Meyer, M., Thurman, E., Zaaugg, S., Barber, L. and Buxton, H.; 2002; Pharmaceuticals, hormones, and other organic wastewater contminants in US streams, 1999-2000: a national reconnaissance; Env. Sci. & Tech.; 36:6:1202
583 USGS; 2007; USGS Errata for pharmaceuticals, hormones, and other organic wastewater contaminants in US streams, 1999-2000: a national reconnaissance, Environmental Science & Technology, 36:6:1202, 2002.; http://toxics.usgs.gov/regional/est_errata.html; As posted on August 26, 2007. U.S. Geological Survey.