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Risks of Endocrine Disrupting Chemicals in Discharges from Concentrated Animal Feeding Operations

Project Summary

Masculinization of female fathead minnows exposed to 17-trenbolone - a growth promoter commonly used by cattle farmers in North America. (a) Control male, (b) control female, and (c) female exposed to 5,000 ng 17-trenbolone/L.

There are an estimated 1.3 million farms holding livestock in USA. About 238,000 of these farms are considered concentrated animal feeding operations (CAFOs). CAFOs annually produce more than 500 million tons of animal waste that could pose substantial risks to the environment and public health. At present, there is evidence that CAFO waste has a potential to introduce hormonally-active materials into surface and ground waters, as well as (through manure applications) to terrestrial systems.

Our overall goal is to characterize the magnitude and extent of the impact of estrogenic and androgenic hormones in waste from CAFOs and determine the impact of current CAFO waste management strategies on the fate and effects of hormones. We are currently collaborating with multiple EPA researchers (NERL, NRMRL, NHEERL) and extramural researchers funded through the NCER STAR grants program to achieve the following:

Key products

Durhan, E.J., C.S. Lambright, E.A. Makynen, J. Lazorchak, P.C. Hartig, V.S. Wilson, L.E. Gray,  and G.T. Ankley. 2006. Identification of metabolites of trenbolone acetate in androgenic runoff from a beef feedlot. Environmental Health Perspectives 114(Suppl.1):65-8.

Jensen, K.M., E.A. Makynen, M.D. Kahl, and G.T. Ankley. 2006. Effects of the feedlot contaminant 17alpha-trenbolone on reproductive endocrinology of the fathead minnow. Environmental Science & Technology  40:3112-7. 

Miller, D.H. and G.T. Ankley. 2004. Modeling impacts on populations: Fathead minnow (Pimephales promelas) exposure to the endocrine disruptor 17beta-trenbolone as a case study. Ecotoxicology and Environmental Safety 59:1-9.

Ankley, G.T., K.M. Jensen, E.A. Makynen, M.D. Kahl, J.J. Korte, M.W. Hornung, T.R. Henry,  J.S. Denny, R.L. Leino, V.S. Wilson, M.C. Cardon, P.C. Hartig, and L.E. Gray. 2003. Effects of the androgenic growth promoter 17-beta-trenbolone on fecundity and reproductive endocrinology of the fathead minnow. Environmental Toxicology and Chemistry 22:1350-60.

Ankley, G.T., K.M. Jensen, M.D. Kahl, J.J. Korte, and E.A. Makynen. 2001. Description and evaluation of a short-term reproduction test with the fathead minnow (Pimephales promelas). Environmental Toxicology and Chemistry 20:1276-90.

Project personnel


Name E-mail Phone
Gerald Ankley ankley.gerald@epa.gov 218-529-5147
Lindsey Blake blake.lindsey@epa.gov 218-529-5237
Elizabeth Durhan durhan.elizabeth@epa.gov 218-529-5167
Kathleen Jensen jensen.kathleen@epa.gov 218-529-5177

Research project update date

February 28, 2008

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