天美传媒

Abstract

Estrogenic compounds, particularly the synthetic estrogenic steroids-ethinyl estradiol (EE2) and mestranol (MeEE2) and natural hormone steroids-estrone (E1), estradiol (E2) and estriol (E3), have attracted a great deal of scientific and public attention during recent years due to their occurrence in surface waters and sewage treatment plant effluents and their potential adverse effects on the development and reproduction of fish, wildlife and even human beings. In this presentation, we will focus on our research on the occurrence, sources, and microbial and photochemical degradation of both synthetic and natural estrogenic steroids in fresh and marine aquatic environments and their effects on public health during the past decade. To face analytical challenges for determining trace amounts of estrogenic steroids in natural waters, GC-MS and HPLC analytical methods have been developed. The developed methods were applied to the water samples periodically collected from wastewater treatment plants, lakes, Acushnet River and Buzzards Bay. The interested compounds were detected in several of water samples in nano to micro-gram per liter concentration range, can certainly cause fish feminization and may also contribute to the observed declines in American lobster population in Buzzards Bay. Microbial and photochemical degradation of E1, E2, E3, EE2 and MeEE2 have been also investigated in seawater as well as in waste, lake and river waters as a comparison. The microbial degradation of synthetic steroid estrogens is extremely slow with a half-life of longer than 70 days in seawater. However, the photo degradation of these compounds is much faster with a half-life of 17 hours for EE2 and 19 hours for MeEE2. Humic and other dissolved organic substances significantly accelerate the sunlight-induced photo degradation of estrogenic steroids. Transition metal Fe(III), nitrate and nitrite can further catalyze the photochemical decomposition of these steroids.

Biography

Email: yzuo@umassd.edu