Home Archived April 13, 2016

U.S. Geological Survey

Maps, Imagery, and Publications Hazards Newsroom Education Jobs Partnerships Library About USGS Social Media

USGS Newsroom

USGS Newsroom  

Endocrine Disruptors and Intersex Fish Identified in Minnesota Lakes
Released: 11/1/2010 10:00:00 AM

Contact Information:
U.S. Department of the Interior, U.S. Geological Survey
Office of Communication
119 National Center
Reston, VA 20192
Jennifer LaVista 1-click interview
Phone: 303-202-4764

Endocrine disrupting chemicals were identified in all of the 11 Minnesota lakes studied by the U.S. Geological Survey, St. Cloud State University and the Minnesota Pollution Control Agency.

Related Podcasts

Endocrine Disruptors and Intersex Fish in Minnesota Lakes

download Download directly | Details

podcast icon  itunes icon
or subscribe by e-mail.

Female characteristics were observed in male fish in most of the lakes studied. Less than 10 percent of caged minnows placed in the lakes for 21 days showed signs of intersex, which can be caused by exposure to endocrine disrupting chemicals.

Although endocrine disrupting chemicals and endocrine disruption in both resident fish and caged minnows were generally more pronounced in lakes surrounded by urban and agricultural lands, they were also identified in more remote lakes. Further studies are needed to determine if there is a link between the prevalence of these chemicals and surrounding land use. The full study can be found in the journal Science of the Total Environment.

The lakes studied include Budd, Cedar, Elk, Kabetogama, Northern Light, Owasso, Red Sand, Shingobee, Stewart, Sullivan, and White Sand. The 11 lakes are spread across the state and surrounded by multiple types of land-cover, including urban, forested and agricultural lands. Wastewater treatment plant discharges were absent from all of the lakes.

“We were surprised to see the same types of compounds found in wastewater treatment plant discharges in these Minnesota lakes,” said USGS scientist Jeffrey Writer. “This study illustrates a need for future research to learn more about where these chemicals are coming from and the potential effects on the fish.”

Although small amounts of steroidal hormones were detected in all of the lakes, they were found at levels that could cause potential ecological effects. Other potential endocrine disrupting compounds, including bisphenol A, were found at concentrations similar to those found at WWTP outputs. 

Contaminants can enter lakes from variety of non-point sources, such as: farming, stormwater runoff, animal feeding operations, septic systems, recreational activities, transportation and atmospheric deposition.

Vitellogenin, an egg yolk protein commonly produced by female fish but generally absent in male fish was used to evaluate endocrine disruption. Elevated levels of this protein were identified in male fish in most of the lakes surveyed.

This USGS study is part of an ongoing program with St. Cloud State University and the Minnesota Pollution Control Agency to look at the water quality of lakes in Minnesota. More information can be found at the USGS Emerging Contaminant and Endocrine Studies in Minnesota website.

For a podcast interview with USGS scientist Jeffrey Writer, listen to episode 135 of CoreCast

USGS provides science for a changing world. Visit USGS.gov, and follow us on Twitter @USGS and our other social media channels.
Subscribe to our news releases via e-mail, RSS or Twitter.

Links and contacts within this release are valid at the time of publication.



Accessibility FOIA Privacy Policies and Notices

USA.gov logo U.S. Department of the Interior | U.S. Geological Survey
URL: http://www.usgs.gov/newsroom/article.asp?ID=2630
Page Contact Information: Ask USGS
Page Last Modified: 11/1/2010 7:15:43 AM