(Phys.org)—Professor Charles Tyler of the University of Exeter in Britain (and colleagues)
has conducted a study of the impact of chemicals from human waste treatment plants in rivers and streams on the fish that live in them. He has told the press before presenting the findings formally that they have found a very large number of male fish exhibiting female characteristics.
Tyler and his team are scheduled to offer a lecture at this year's Symposium of the Fisheries Society in the British Isles at Exeter University outlining their findings. Among other things, they have observed male fish laying eggs and signs of other
male fish becoming transgender.
The problem, he said, is the chemicals that flushed down the toilets, many of them in our urine. One source in particular has become a major concern—birth control pills. They have a major impact on creatures living in the
water systems where chemicals removed from wastewater are dumped. Another group of chemicals causing a lot of problems for
underwater creatures is antidepressants. Just as in humans, they cause behavioral changes in fish—making some less shy, for example, which makes them easier for prey to catch. Other chemicals in cleaning agents, plastics and cosmetics are also causing problems for fish and other wildlife.
Read more at:
https://phys.org/news/2017-07-freshwater-male-fish-exposed-chemicals.html#jCp