Conversion and Estrogenicity of 17β-estradiol During Photolytic/Photocatalytic Oxidation and Catalytic Wet-air Oxidation.

Estrogen 17β-estradiol (E2), produced by human body and excreted into municipal wastewaters, belongs to the group of endocrine disrupting compounds that are resistant to biological degradation. The aim of this study was to assess the efficiency of E2 removal from aqueous solutions by means of catalytic wet-air oxidation (CWAO) and photolytic/photocatalytic oxidation. CWAO experiments were conducted in a trickle-bed reactor at temperatures up to 230 °C and oxygen partial pressure of 10 bar over TiO2 and Ru/TiO2 solids.

Membrane Changes Associated with Exposure of Pseudomonas putida to Selected Environmental Pollutants and their Possible Roles in Toxicity.

A bacterial model system (Pseudomonas putida DSM 50026) was used in this research to assess potential effect of five selected chemically diverse environmental pollutants on cell membranes. Long chain fatty acid profiles of cultures exposed to environmentally relevant concentrations of atrazine (ATR), metolachlor (MET), pentachlorobiphenyl (PCB), hexachlorobenzene (HCB) and fluoranthene (FL), were analyzed and compared to non-exposed cultures. To assess sensitivity of membrane-based responses, the impact of each toxicant on culture growth was also followed spectrophotometrically.

Comparison of Fenton's oxidation and ozonation for removal of estrogens.

This study compares efficiency of Fenton's oxidation and ozonation of 17beta-estradiol (E2) and 17alpha-ethinylestradiol (EE2) as two possible processes for removal of estrogens from aqueous solutions. The effectiveness of Fenton's oxidative removal was studied at different ratios of reagents Fe2+:H2O2 (1:0.5; 1:10; 1:20; 1:33), where with some molar ratios up to 100% removal of E2 and EE2 was achieved in the first few minutes of reaction.

Feasibility of Fenton's Oxidation for Removal of Estrogens from Aqueous Solutions.

Presented research has been focused on the effectiveness of degradation of natural (17-estradiol - E2) and synthetic (17α-ethinylestradiol - EE2) hormones with Fenton's oxidation. Numerous studies have demonstrated, that the impact of hormones on organisms was shown already at environmental concentrations close to 1 pg L-1, so their effective removal from wastewaters is important. Fenton's oxidation is very efficient in terms of oxidation of organics, while its main withdrawal is the formation of waste sludge, leading to adsorption of organics, which sometimes makes it impossible to reliably value the extent of actual degradation.