Researchers at the University of Minnesota have discovered high levels of estrogens from plant sources in some industrial wastewater.
These chemicals, called phytoestrogens, can mimic hormones and alter developmental and reproductive patterns in fish. Research has shown some negative effects on humans, too. Researcher Paige Novak of the University of Minnesota says pharmaceuticals from human waste are one possible source.
Novak's research looked at industrial facilities such as biodiesel plants and a soy milk factory, and indicates these facilities may be processing natural plant-based compounds at higher concentrations than are naturally found in the environment.
"When you process something like a soybean, and you crush it and you mill it and you expose it to water, these compounds then leech into the water, and then they go out with the wastewater," she said.
This is the first study of its kind to examine a wide range of plant processing facilities.
Novak says some of these phytoestrogens can be removed through standard wastewater treatment, but sometimes levels that may damage fish still remain. The research findings are particularly important because the more sources of phytoestrogens are accurately identified, the better estrogen can be removed from surface water.
The research has been peer-reviewed and will appear in the journal Environmental Toxicology and Chemistry in the fall.