Environmental Health - Toxic Substances
Tackling Fish Endocrine Disruption
USGS scientist dissecting a fish to determine possible effects from exposure to endocrine disrupting contaminants
Exposure to low-levels of some contaminants can cause disruption of endocrine functions in animals, such as reproduction. This is done by modulating, mimicking, or interfering with normal hormonal activity. Examples of endocrine-active contaminants are chemicals such as synthetic hormones, certain pesticides, some pharmaceuticals, detergents degradation products (nonylphenol), and many others.
Selected USGS Information on Endocrine Disruption
Intersex, the presence of both male and female characteristics within the same fish, is being observed in fish in more streams across the Nation. Intersex is one manifestation of endocrine disruption in fish. Endocrine disruption can result in adverse effects on the development of the brain and nervous system, the growth and function of the reproductive system, and the response to stressors in the environment. U.S. Geological Survey (USGS) scientists have documented the presence of endocrine disrupting contaminants in rivers and streams across the Nation. Additionally, USGS scientists and others have demonstrated that exposure to endocrine-active contaminants can cause endocrine disruption, which can have ruinous impacts on fish populations. The following are some recent examples of USGS studies on endocrine disruption in fish.
Blazer, V.S., Iwanowicz, L.R., Iwanowicz, D.D., Smith, D.R., Young, J.A., Hedrick, J.D., Foster, S.W., and Reeser, S.J., 2007, Intersex (testicular oocytes) in smallmouth bass from the Potomac River and selected nearby drainages: Journal of Aquatic Animal Health, v. 19, no. 4, p. 242-253, doi:10:1577/H07-031.1.
Ripley, J., Iwanowicz, L., Blazer, V., and Foran, C., 2008, Utilization of protein expression profiles as indicators of environmental impairment of smallmouth bass (Micropterus dolomieu) from the Shenandoah River, Virginia, USA: Environmental Toxicology and Chemistry, v. 27, no. 8, p. 1756-1767, doi:10.1897/07-588.1.
Schoenfuss, H.L., Bartell, S.E., Bistodeau, T.B., Cediel, R.A., Grove, K.J., Zintek, L., Lee, K.E., and Barber, L.B., 2008, Impairment of the reproductive potential of male fathead minnows by environmentally relevant exposures to 4-nonylphenol: Aquatic Toxicology, v. 86, no. 1, p. 91-98, doi:10.1016/j.aquatox.2007.10.004.
Vajda, A.M., Barber, L.B., Gray, J.L., Lopez, E.M., Woodling, J.D., and Norris, D.O., 2008, Reproductive disruption in fish downstream from an estrogenic wastewater effluent: Environmental Science and Technology, v. 42, no. 9, p. 3,407-3,414, doi:10.1021/es0720661.
Barber, L.B., Lee, K.E., Swackhamer, D.L., and Schoenfuss, H.L., 2007, Reproductive responses of male fathead minnows exposed to wastewater treatment plant effluent, effluent treated with XAD8 resin, and an environmentally relevant mixture of alkylphenol compounds: Aquatic Toxicology, v. 82, no. 1, p. 36-46, doi:10.1016/j.aquatox.2007.01.003.
Chambers, D.B., and Leiker, T.J., 2006, A reconnaissance for emerging contaminants in the South Branch Potomac River, Cacapon River, and Williams River Basins, West Virginia, April-October 2004: U.S. Geological Survey Open-File Report 2006-1393, 28 p.
Hinck, J., Blazer, V., Denslow, N., Echols, K., Gale, R., Wieser, C., May, T., Ellersieck, M., Coyle, J., and Tillitt, D., 2008, Chemical contaminants, health indicators, and reproductive biomarker responses in fish from rivers in the Southeastern United States: Science of the Total Environment, v. 390, no. 2-3, p. 538-557, doi:10.1016/j.scitotenv.2007.10.026.
Lee, K.E., Schoenfuss, H.L., Jahns, N.D., Brown, G.K., and Barber, L.B., 2008, Alkylphenols, other endocrine-active chemicals, and fish responses in three streams in Minnesota--Study design and data, February-September 2007: U.S. Geological Survey Data Series 405, 44 p (plus appendixes).