In the last decade, studies have revealed that endocrine disrupting chemicals, or EDC’s, are present in virtually every watershed in the United States. There is growing concern that even at low concentrations, these chemicals may adversely affect fish, wildlife, ecosystems, and human health. For this reason, the Minnesota legislature commissioned a statewide MPCA study on the presence and effects of endocrine disrupting chemicals in Minnesota’s lakes and rivers.
Endocrine disrupting chemicals are a group of compounds that can encompass anything from industrial solvents to pharmaceuticals. The are normally associated with wastewater discharge. When an organism, whether it’s a fish, or any other organism, is exposed to an endocrine disrupting compound, it mimics hormones and interacts with the endocrine system, causing adverse effects.
Twelve lakes and 4 rivers around the state were sampled for the MPCA study. They were selected to represent a wide range of land use and development. Northern Light Lake, in Cook County, was chosen as a reference lake because of its remote location and absence of development. Researchers thought the lake would be free of chemical contamination, but it didn’t turn out that way. Several chemicals commonly associated with wastewater were found in the sediment and surface water of Northern Light Lake, including carbamazepine, a drug used to treat Attention Deficit Hyperactivity Disorder, the painkiller acetaminophen, Bisphenol A, and the insecticide DEET. Finding these compounds in a lake with no development or obvious sources of pollution came as a surprise to the MPCA.
“Right now it’s still early in trying to figure out exactly where these compounds are coming from and what it means for the environment,” said Mark Ferrey of the MPCA. “And right now we don’t have the answers to all of those things. For example, the compounds that we’ve been talking about are found typically in part per trillion concentrations in the surface water and sediment. Now to give your listeners an idea of how small a concentration a part per trillion is, it is equivalent of one drop in 20 Olympic sized swimming pools. A lot of people, when they hear that, will think that can’t possibly be a big problem.”
However, studies have shown that even at parts per trillion concentrations, there are observable effects on fish and wildlife from exposure to endocrine active chemicals. At an experimental lakes region in Canada, researchers dosed a closed lake to five parts per trillion with a synthetic hormone commonly found in birth control pills. Within two years, the entire minnow population of the lake collapsed, followed by the trout population.
More than 80,000 chemicals are manufactured worldwide and an unknown number may possess endocrine disrupting properties. These chemicals are used to manufacture products used by consumers every day. They’re turning up in the environment, and in our bodies. One example is the chemical Bisphenol A, used routinely in the manufacture of baby bottles, water bottles and canned food liners. It’s been in the news lately and was recently linked to a host of medical problems including cancer and reproductive issues. It’s estimated that 92 percent of all Americans, including children, have measurable amounts of Bisphenol A in their urine.
Public awareness about exposure to endocrine active chemicals is growing, and there is increasing pressure in Washington to reform the nation’s chemical safety laws to deal with this emerging health issue.
Legislation to reform the nation’s chemical safety laws was introduced in the U.S. Congress in 2008. The Kids-Safe Chemicals Bill would update the Toxic Substances Control Act of 1976 and is intended to protect Americans, especially children, from harmful chemicals found in everyday consumer products. The bill would ensure for the first time that all the chemicals used in baby bottles, children’s toys and other products are proven to be safe before they are put on the market. New Jersey Senator Frank Lautenberg is one of the sponsors of the legislation. In a press release, Lautenberg said, “Every day, consumers rely on household products that contain hundreds of chemicals. The American public expects the federal government to keep families safe by testing chemicals—but the government is letting them down.”
Find out more about the Kids-Safe Chemicals Act.
Learn more about the MPCA study on endocrine disrupting chemicals in Minnesota’s lakes and rivers.