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Environmental Studies

Endocrine Disrupters and the Pill

How EDs Work
Our Stolen Future
Drugs in the Environment
Examples of EDs
Government Testing
The Pill as an ED
History of the Pill
Case Study: Coastal Waters
Case Study: Fish
Case Study: Men in Italy
What you can do!
Further Information

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Case Study:Fish

   With the concentration on marine environments, recent studies in Washington state and Canada have found the detrimental effects of synthetic estrogens can be especially extreme on male fish. Two separate studies conducted in June of 2003 found that synthetic estrogens have two major affects on male fish populations. One found that synthetic estrogens seriously affect the fertility of male rainbow trout salmon. The second study found that fish in a lake in Ontario lost many of their male traits and became feminized. The first study found that fish in Western Washington state found that synthetic estrogens have shown up in rivers, lakes, and even Puget Sound. The research conducted by scientists at the Battelle Marine Sciences Laboratory in Sequim. The study examined the impact of synthetic estrogens on adult trout instead of juveniles. During the tests, "adult trout in caged pens were exposed to ethynylestradiol, a synthetic estrogen. After two months of exposure, the fish were spawned with a healthy female. Researchers discovered that the exposed trout were half as fertile as fish kept in clean water" (Stiffler). Scientists noted that fish were not the only animals affected by synthetic estrogens. Amounts of the estrogens have been found in frogs, river otters, and other fish species making the "male species less male" (Stiffler). Further research is planned to see how much of a concentration is needed to affect fertility in species.
    According to a study by Canadian scientists fish that are exposed to synthetic estrogens become feminized in their traits. In the study, scientists put chemicals from birth control pill into a remote lake in Ontario. Their experiment showed that "all male fish in the lake- from tiny tadpoles to large trout- were "feminized," meaning they had egg proteins growing abnormally in their bodies" (Borenstein).  In fact, the impact of the synthetic estrogens caused the population of the Fathead minnow in the lake, one that had numbered in the thousands, to fall to nearly zero, because of the inability of the fish to reproduce. The findings of this experiment were truly startling, and have raised more concerns about the growing problems of EDs in the environment. These results also show the repercussions that will affect large areas of wildlife. This is not just a problem in fish; instead it will spread through the food chain following the principals of biomagnification and end up impacting other wildlife as well as humans. Synthetic estrogens are a very real threat, and experiments on fish have shown this.

All information on this page refers to two articles hosted on the Our Stolen Future website: One by Seth Borenstein and the other by Lisa Stiffler

Last updated:  5/2/2006


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