Transgender fish found in British Rivers

From flushing harsh chemicals down the toilet.

Sunny London, stop flushing your birth control, cosmetics, plastics and cleaning agents down the toilet. You’re mutating your river fish.

A study has found that 20 percent of male river fish are developing female traits.

Professor Charles Tyler from the University of Exeter discovered that some male river fish have started producing eggs while others are displaying highly aggressive behaviour and exhibiting lower sperm efficiency which is causing erratic breeding patterns.

The chemicals in the by-products and medication being flushed down the toilet have been found to be responsible for the fish’s strange changes. Tyler explains:

We are showing that some of these chemicals can have much wider health effects on fish that we expected. Using specially created transgenic fish that allow us to see responses to these chemicals in the bodies of fish in real time, for example, we have shown that oestrogens found in some plastics affect the valves in the heart.

The tests concluded that male freshwater fish- like the roach fish had feminine qualities.

Other research has shown that many other chemicals that are discharged through sewage treatment works can affect fish, including antidepressant drugs that reduce the natural shyness of some fish species, including the way they react to predators

The finalised report and findings will be presented as part of the 50th Anniversary Symposium of the Fisheries Society in the British Isles this week.

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