Manure generated by dairy farms contains excreted natural estrogens and their conjugates, as well as other hormones that have been used to increase milk production. Therefore, when manure is applied to fertilize croplands, these hormones may be spread in the environment and can potentially reach surface water by run-off, especially when a heavy rain event occurs immediately after land application. Livestock farms implement manure storage and treatment systems to decrease nutrient loading to the environment. Therefore, it is important to evaluate the extent at which estrogens are removed during storage or treatment of manure prior to land application. In this study, the concentrations of estrogens [estrone (E1), 17ߖestradiol (E2), estriol (E3)] and their conjugated forms (glucuronides and sulfates) were evaluated in an advanced digestion facility (CH4 BiogasTM). This facility includes a pasteurization step, followed by a 22-day anaerobic digestion process. All samples were analyzed by enzyme-linked immunosorbent assay (ELISA), yeast estrogen screen (YES) assay, and liquid chromatography- tandem mass spectrometry (LC/MS-MS). The results from YES assay showed a much higher E2-equivalent than the E2 concentrations observed in ELISA. This could mean that there are many other hormones present in the manure that have significant estrogenic activity. Increase in E1 concentration after digestion indicates deconjugation of glucuronides and sulfated conjugates. The sample matrix affected the analysis using both ELISA and LC/MS-MS, indicating that improved sample preparation is necessary.

Assessing the removal of hormones and their potency as endocrine-disrupting chemicals in dairy wastes through an anaerobic digestion system

246th National Meeting (2013)

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.