Fate of 17α-ethynylestradiol in the presence of vegetable wastes.

Abstract

Estrone (E1), Estradiol (E2), 17α-Ethynylestradiol (EE2), and Estriol (E3) are estrogens that can result in endocrine disrupting effects in human and wildlife populations, impacting reproduction and development. Estrogens display characteristics typical of organic compounds and are typically excreted in conjugated forms, with rapid conversion to the unconjugated molecules in the environment. Entry to the environment can occur via multiple pathways which minimize the possibility of source control as a remediation strategy and, as such responsibility for their removal falls on wastewater treatment plants. As expected the majority of research on the control of estrogens is reported in the municipal wastewater treatment literature. A recent study assessed the abiotic transformation of Estrogens in the presence of model vegetable matter (rabbit food). That study stipulated the catalytic or enzymatic polymerization of E1, E2, E3 and EE2 in the presence of rabbit food and dissolved oxygen. Greater than 80percent reduction in the parent compounds was achieved for each target estrogen after 72 h of exposure. Interestingly testosterone, androstenedione and progesterone did not undergo any such transformation when exposed to the same conditions. It was speculated that the presence of a phenolic group in the estrogen skeleton was responsible for polymer formation. This study was undertaken to demonstrate a treatment process for the removal of estrogens from water matrices using vegetable matter. Comparison of four extraction procedures Accelerated Solvent Extraction (ASE), conventional solvent based extraction, Soxhlet extraction, and ultra-sonication was carried out using environmentally relevant concentrations. ASE and ultra-sonication techniques proved the most efficient in extracting EE2 from the three substrates investigated (rabbit food (RF), Soil and Ottawa Sand. ASE yielded recoveries of EE2 of 81.2percent, and 77.5percent from RF and soil substrates, respectively. Sonication yielded comparable recoveries of 73.4, and 72.3