The Economic Times

A synthetic hormone was added to a remote Canadian lake in tiny amounts then an entire fish population nearly collapsed

A synthetic estrogen introduced into a Canadian lake caused a significant ecological shock. This chemical, present in tiny amounts, severely disrupted fathead minnow reproduction. Male fish exhibited hormonal changes and reproductive organ abnormalities after exposure. The fathead minnow population subsequently collapsed, with young fish disappearing. This experiment demonstrated how low contaminant concentrations can yield large ecosystem effects.