ISTC Senior Chemist Wei Zheng received funding from the U.S. Department of Agriculture to study the fate and transport of hormones and antibiotics from cattle farms. He recently submitted the following update to the USDA and agreed to share it with The GLRPPR Blog as well. The questions below were posed by the funder. For more information about this project, please contact Wei Zheng.
What is the water problem being addressed by your project? What are the main goals of your project?
Large volumes of manure-contaminated wastewater, wash water, and storm water runoff can be generated at concentrated animal feeding operations (CAFOs). The reuse of CAFO wastewater on agricultural lands can decrease the amount of wastewater discharge into sensitive water bodies and beneficially utilize the nutrients in the discharge as fertilizers for irrigation applications. However, the wastewater from large confined-animal farms usually retains many contaminants, such as salts, pathogens, heavy metals, hormones, antibiotics, and excess amounts of nutrients, which could pose environmental and public health risks if widely applied for agricultural irrigation. This project focuses on how wastewater reuse from dairy and beef farms contributes to the problem of animal hormones and veterinary antibioticsin the environment. The primary goal of this project is to investigate the environmental fate and transport of several commonly-occurring steroid hormones, veterinary antibiotics, and their metabolites derived from the agricultural use of CAFO manure and wastewater; minimize their contamination in soil and water; and thereby develop effective management strategies to protect valuable water supplies.
Who are your stakeholders and what has been the impact of your work on your stakeholders? Describe any new technologies that were developed from your work. Are your stakeholders implementing this new technology and if so, how many have implemented the technology? What new knowledge was gained?
This project adds to the body of knowledge concerning the environmental fate and transport of steroid hormones and veterinary antibiotics derived from CAFOs. Successful completion of this project will help the federal and state agencies to formulate effective regulatory programs, help animal farm operators to improve their land application design and operation processes, and help extension staff to develop effective management strategies to minimize the negative environmental effects of hormone and antibiotic contaminants on the surrounding water supplies. Our initial research investigated the transformation kinetics and mechanisms of three steroid hormones (17α-estradiol, 17β-estridiol and estrone) and two antibiotics (ceftiofur and florfenicol) in dairy lagoon and beef recycled wastewater. Our initial results suggest that increasing the residence time of wastewater in lagoon or aerobic settling tanks may be an economical, feasible, and efficient practice to degrade hormone and antibiotic contaminants and thus reduce their loads to the environment. These results will be useful for development of integrated management strategies to mitigate potential adverse impacts associated with the reuse of CAFO wastewater.