The study, led by scientists at the Illinois Sustainable Technology Center, is the first to document the unusual behavior of estrogens in wastewater lagoons. The study appears in the journal Environmental Science & Technology.
Just as new mothers undergo hormonal changes that enable them to breastfeed, lactating cows generate estrogenic hormones that are excreted in urine and feces, said ISTC senior research scientist Wei Zheng, who led the study. In large “confined animal feeding operations” (CAFOs) the hormones end up in wastewater. Farmers often store the wastewater in lagoons and may use it to fertilize crops.
Federal laws regulate the flow of nutrients such as nitrogen and phosphorous from CAFOs to prevent excess nutrients from polluting rivers, streams, lakes or groundwater. Environmental officials assume that such regulations also protect groundwater and surface waters from contamination with animal hormones and veterinary pharmaceuticals, but this has not been proven.
Hormone concentrations in livestock wastes are 100 to 1,000 times higher than those emitted from plants that treat human sewage, and large dairy farms are a primary source of estrogens in the environment, Zheng said. Recent studies have detected estrogenic hormones in soil and surrounding watersheds after dairy wastewater was sprayed on the land as fertilizer.
“These estrogens are present at levels that can affect the (reproductive functions of) aquatic animals,” Zheng said. Even low levels of estrogens can “feminize” animals that spend their lives in the water, causing male fish, for example, to have low sperm counts or to develop female characteristics (such as producing eggs), undermining their ability to reproduce.
Hormones that end up in surface or groundwater could contaminate sources of drinking water for humans, Zheng said. “The estrogens may also be taken up by plants – a potential new route into the food chain,” he said.
While conducting the new study on dairy waste lagoon water in the lab, the researchers were surprised at first to see levels of three primary estrogens (17 alpha-estradiol, 17 beta-estradiol and estrone) fall and then rise again in their samples. Further analysis revealed that the estradiols were being converted to estrone, undergoing the normal first step of biodegradation. But then the process reversed itself: Estrone was reverting to the alpha- and beta-estradiols.
“We call this a reverse transformation,” Zheng said. “It inhibits further degradation. Now we have a better idea of why (the estrogens) can persist in the environment.”The degradation rates of the three hormones in the wastewater solution were temperature-dependent, and very slow. After 52 days at 35 degrees Celsius (95 degrees Fahrenheit) – an ideal temperature for hormone degradation, Zheng said – less than 30 percent of the hormones in the solution had broken down.
The fluctuating levels of estrone and estradiols may lead to detection errors, Zheng said, giving the impression that the total estrogen load of wastewater is decreasing when it is not.
“We need to develop a strategy to prevent these hormones from building up in the environment,” he said.Researchers from the Agricultural Research Service of the U.S. Department of Agriculture also contributed to this study. The USDA supported this research.
The Illinois Sustainable Technology Center is a division of the Prairie Research Institute at the U. of I.Editor’s notes: To reach Wei Zheng, call:217-333-7276;
Diana Yates | University of Illinois
Bioinvasion on the rise
15.02.2017 | Universität Konstanz
Litter Levels in the Depths of the Arctic are On the Rise
10.02.2017 | Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung
In the field of nanoscience, an international team of physicists with participants from Konstanz has achieved a breakthrough in understanding heat transport
Cells need to repair damaged DNA in our genes to prevent the development of cancer and other diseases. Our cells therefore activate and send “repair-proteins”...
The Fraunhofer IWS Dresden and Technische Universität Dresden inaugurated their jointly operated Center for Additive Manufacturing Dresden (AMCD) with a festive ceremony on February 7, 2017. Scientists from various disciplines perform research on materials, additive manufacturing processes and innovative technologies, which build up components in a layer by layer process. This technology opens up new horizons for component design and combinations of functions. For example during fabrication, electrical conductors and sensors are already able to be additively manufactured into components. They provide information about stress conditions of a product during operation.
The 3D-printing technology, or additive manufacturing as it is often called, has long made the step out of scientific research laboratories into industrial...
Nature does amazing things with limited design materials. Grass, for example, can support its own weight, resist strong wind loads, and recover after being...
Nanometer-scale magnetic perforated grids could create new possibilities for computing. Together with international colleagues, scientists from the Helmholtz Zentrum Dresden-Rossendorf (HZDR) have shown how a cobalt grid can be reliably programmed at room temperature. In addition they discovered that for every hole ("antidot") three magnetic states can be configured. The results have been published in the journal "Scientific Reports".
Physicist Dr. Rantej Bali from the HZDR, together with scientists from Singapore and Australia, designed a special grid structure in a thin layer of cobalt in...
13.02.2017 | Event News
10.02.2017 | Event News
09.02.2017 | Event News
24.02.2017 | Life Sciences
24.02.2017 | Life Sciences
24.02.2017 | Trade Fair News