Oxidation of bisphenol A, 17β‐estradiol, and 17α‐ethynyl estradiol and byproduct estrogenicity

Abstract

A human breast cancer cell line (MCF-7) was used to investigate the cumulative estrogenicity profiles elicited during the oxidation of three estrogenic compounds [bisphenol A (BPA), 17beta-estradiol (E2), and 17alpha-ethynyl estradiol (EE2)]. High-performance liquid chromatography (HPLC) with a method detection limit (MDL) of approximately 1 nM was used to measure the initial and final concentrations of test compounds during oxidation. Both chlorination and ozonation removed from 75% to >99% of the test compounds in distilled water. Increasing contact time and chlorination dose improved compound removal. Chlorination byproducts of BPA, E2, and EE2 elicited low levels of estrogenicity over an extended period of time. For equivalent molar oxidant dosages, ozone and chlorine had comparable residual proliferative effect values and >99% loss of the parent compounds. For oxidation studies of estrogenic chemicals, ammonium chloride was found to adequately quench residual chlorine without interfering with cell culture assay. Oxidation of test compounds with chlorine and ozone resulted in a similar estrogenicity trend, with a relative higher level of estrogenicity elicited during the early phases of oxidation, which gradually dissipated over the extended exposure time to a stable point. Oxidation with ozone resulted in the rapid transformation of test compounds, reaching a stabilized estrogenic level in 10 min, whereas for chlorination it took more than 120 min for elicited estrogenicity to stabilize.

Treatment options for wastewater effluents from pharmaceutical companies

“…Chlorine dioxide is also effective for the removal of sulfamethoxazole, roxithromycin, 17α-ethinylestradiol and diclofenac (Khetan and Collins, 2007). Chlorination and ozonation when compared for the removal of bisphenol A, 17β-estradiol, and 17α-ethinylestradiol and byproduct estrogenicity from distilled water showed comparable results with ozonation resulting in 75-99 % removal (Alum et al, 2004). Residual chlorine and ozone was found to be low with > 99 % loss of the parent compound (Gharbani et al, 2010).…”

“…Chlorination has been shown to be effective for the removal of pharmaceuticals including 17α-ethinylestradiol and 17 β-estradiol (Alum et al, 2004) and sulfonamides (Qiang et al, 2006). Chlorine dioxide is also effective for the removal of sulfamethoxazole, roxithromycin, 17α-ethinylestradiol and diclofenac (Khetan and Collins, 2007).…”

Removal of Endocrine Disruptors from Urban Wastewater by Advanced Oxidation Processes (AOPs): A Review

“…Alum et al [61] monitored both concentration and estrogenic activity of BPA during 120 min ozonation, carried out under operating conditions resembling the ones applied in full-scale drinking water treatment facilities. They observed that the level of estrogenic activity first increased and then slightly reduced before reaching stability after 60 minutes.…”

Destruction of Estrogens Using Fe-TAML/Peroxide Catalysis

“…Although much cheaper, chlorination is less effective than ozonation (20) and complicated by toxic as well as estrogenic byproducts. Chlorine treatment required at least two hours to remove estrogenic activity from 17 -E2 solutions, while activity in EE2 solutions was still elevated after 24 h (assessed by E-Screen) (20). Moreover, estrogenic activity was actually found to increase during the chlorination process for both 17 -E 2 and E2 (20).…”