Tiny amounts of cocaine flushed into rivers is causing eels to become not only hyperactive but to suffer muscle wastage, impaired gills and hormonal changes, a study has found.
The impact of traces of cocaine on the physiology of European eels could be hindering their epic migrations through the oceans to reproduce.
The cocaine-exposed eels appeared “hyperactive” and their skeletal muscle showed evidence of serious injury, including muscle breakdown and swelling.
Even after going into 'rehab' – clean waters – for ten days the eels were still found to have damaged muscles and increased cortisol levels. This stress hormone can cause fat wastage, and endangered European eels require fat reserves to make a successful migration to the Sargasso Sea in the west Atlantic, where they breed.