|Casey, Frank - North Dakota State University|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 5/16/2018
Publication Date: N/A
Technical Abstract: Estrogens are steroid hormones eliminated from nearly all animals at reasonably high levels, and when released into the environment they can act as endocrine disrupting compounds, particularly to aquatic organisms. Tracing the movement of estrogens from animal waste to impacted waters is complicated by historical estrogen deposits in soils, as well as their uncontrolled introduction by wildlife. Tracer studies can be conveniently performed with radiochemicals; however, these are not suitable for field research. Stable brominated analogs of estrogens may prove a fruitful method to study the movement of these environmental contaminants in the field. Thus, the aim of this study was to synthesize, characterize, and introduce brominated 17ß-estradiol (Br-E2) analogs into a field setting and monitor the analog movement in soils. Two monobromo and one dibromo 17ß-estradiol analogs were successfully synthesized, and introduced into the surface soil layer of agricultural plots (3 control, no Br-E2; 3 treated with Br-E2; 3 x 3 m) in North Dakota. Corn was planted on the plots, and the plots were constructed with lysimeters 0.6 m below the surface to capture leachate water during the 2017 growing season. Due to drought conditions in the area, which lead to only a limited number of lysimeter samples, soil cores were also taken at the conclusion of the growing season. The cores were divided into 0.5 m sections, and were extracted with water and acetone. Lysimeter water samples and soil extracts were analyzed by TTOF/LC-MS with standards. Down-gradient movement of brominated estradiol analogs was quantified, and conversion to metabolites and degradates was determined. Results will be compared to those obtained previously with radiolabeled analogs in laboratory-scale batch studies in the same soil.