Researchers were studying fish from a North Carolina river when they discovered that some of the males quite literally had lady parts. Male black bass and some sunfish had been developing eggs in their testes, which, as you can guess, isn't a good thing. This research provides further evidence that exposure to estrogen compounds in water is feminizing male fish around the United States.
North Carolina State University researchers tested 20 streams and rivers throughout North Carolina during the 2012 spawning season for contaminants known to disrupt endocrine systems, such as industrial chemicals and pesticides. They also tested black bass—largemouth and smallmouth bass—and sunfish in the rivers for “intersex” characteristics, looking for eggs in the testes of males.
More than 60 percent of the 81 black bass tested intersex, while 10 percent of the 185 sunfish were intersex. They detected 43 percent of the 135 contaminants they were looking for throughout the state. Crystal Lee Pow, a Ph.D. student at North Carolina State University who helped lead the work, said they are still analyzing differences between waterways so aren’t yet disclosing the impacted rivers.
The results are worrisome. In past studies, male fish with eggs have had reduced fertility and sperm production. “Males guard the nest, create spawning nests for young, and guard fertilized eggs,” Lee Pow said. “ Males are crucial for hatching success, and their male behavior could be altered by exposure to contaminants and the presence of the intersex condition.” (source)
This research was in part spurred by a U.S. Geological Survey study in 2009 that showed intersex male fish in nine U.S. river basins and found that the Pee Dee River basin—which spans North Carolina and South Carolina—had the highest rate of intersex fish (80%).
Where is all that estrogen coming from?
“There are also a lot of concentrated animal feeding operations in North Carolina,” Lee Pow said, adding that previous research at North Carolina State found that waste from pigs, which is held in lagoons, can run off into streams after it is applied to land. “The [pig] waste is chock-full of estrogens,” she said.
This makes it particularly important for something to be done about these feedlot operations, yet the EPA apparently doesn't quite know what to do with all that animal waste.
In 2010, after being sued by the Waterkeeper Alliance and other environmental groups, the EPA pledged to reconsider a rule issued during the George W. Bush administration exempting feedlots from having to disclose hazardous emissions to the agency and the public. Five years later, the EPA hasn’t done anything about it. On July 13 agency lawyers went back to court and said the regulations wouldn’t be changed after all. (source)
This inaction is worrying. Like the air we breathe and the soil in which we grow our food, our water is essential to life (all life), and making sure it stays clean should be a very high priority.