Identification of new ozonation disinfection byproducts of 17β-estradiol and estrone in water

Abstract

Estrogens are a class of micro-pollutants found in water at low concentrations (in the ng L(-1) range), but often sufficient to exert estrogenic effects due to their high estrogenic potency. Disinfection of waters containing estrogens through oxidative processes has been shown to lead to the formation of disinfection byproducts, which may also be estrogenic. The present work investigates the formation of disinfection byproducts of 17β-estradiol (E2) and estrone (E1) in the treatment of water with ozone. Experiments have been carried out at two different concentrations of the estrogens in ground water (100 ng L(-1) and 100 μg L(-1)) and at varying ozone dosages (0-30 mg L(-1)). Detection of the estrogens and their disinfection byproducts in the water samples has been performed by means of ultra performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS) with a triple quadrupole (QqQ) and a quadrupole-time of flight (QqTOF) instrument. Both E2 and E1 have been found to form two main byproducts, with molecular mass (MM) 288 and 278 in the case of E2, and 286 and 276 in the case of E1, following presumably the same reaction pathways. The E2 byproduct with MM 288 has been identified as 10 epsilon-17beta-dihydroxy-1,4-estradieno-3-one (DEO), in agreement with previously published results. The molecular structures and the formation pathways of the other three newly identified byproducts have been suggested. These byproducts have been found to be formed at both high and low concentrations of the estrogens and to be persistent even after application of high ozone dosages.

Removal of 17β-Estradiol by Electro-Fenton Process

“…In order to decrease risks of E2 toxicity in water and wastewater, the degradation of this molecule until its removal were investigated by several authors [1][2][3][4][5][6][7][8][9][10][11][12][13][14][15]. Except that according to literature, no study has shown the degradation of the 17β-estradiol using Electro-Fenton process.…”

“…Several studies, based on (AOPs) such as: photocatalytic degradation [1][2][3][4][5], ozonation [6,7], H 2 O 2 photolysis (UV/H 2 O 2 ) [8], photo-Fenton (H 2 O 2 /Fe 2+ /UV) [9][10][11][12], have investigated and showed the degradation of endocrine disrupting chemicals (EDCs).…”

New developments in the trace analysis of organic water pollutants

“…Applying UPLC-MS/MS with QqQ-and QTOF-detectors, two ozonation products of each of the two estrogens 17β-estradiol and estrone were detected. One could be characterized as 10-ε-17β-dihydroxy-1,4-estradieno-3-one, and three others were tentatively identified (Pereira et al 2011). These oxidation by-products were found to be persistent even after application of high ozone dosages.…”

Identification and structural elucidation of ozonation transformation products of estrone

“…The authors also used spectral libraries to identify potential matches. Radjenović, et al [13], de Oliveira Pereira, et al [14] and Larcher, et al [15] employed LC coupled to a hybrid high-resolution mass spectrometer to separate, identify and assign structures to OTPs. Benner and Ternes [16] based the structural elucidation of the OTPs of propranolol on product ion fragmentation trees generated by LC coupled to multi-stage tandem mass spectrometry (MS n ).…”

“…E1 has been observed to be almost completely removed during wastewater disinfection using ozone [24]. However, bench-scale studies investigating the fate and transformation of E1 during ozonation have revealed the formation of OTPs [11,14]. …”