Smithsonian.com

Photo: Keith Marshall

Pharmacological pollutants in water are known to mess with minnow physiology and alter fish behavior. But now, the impacts are getting even more personal for certain species. In a new study in England and Wales, scientists found that hormone-disrupting chemicals may be shrinking the weight of otters’ penis bones. The animals in contaminated sites also experienced an increase in undescended testicles and cysts on their sperm-carrying tubes, the BBC reports.

Scientists examined hundreds of otters to arrive at these grim findings. Previous studies have linked endocrine-disrupting chemicals, such as those found in birth control, to changes in the size of males’ penises and in animals’ other reproductive organs. Traces of pharmaceuticals get flushed out of our systems and wind up in sewage, eventually making their way back into the aquatic ecosystem. The scientists also speculate that dust from industries may be traveling through the atmosphere and carrying contaminants to rivers.

Otters are top predators in the United Kingdom’s river systems, and if they’re having problems, it’s a good indication that the environment they’re living in is suffering. And since otters are mammals, the researchers told the BBC this “could be a warning for all mammals really, which include us humans.”

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