Coked to the gills? Cocaine-laced wastewater can make salmon roam twice as far
The Conversation • • world
Key Points:
- A 2024 study found cocaine and its metabolite benzoylecgonine in wild sharks off Brazil, highlighting the global issue of human drugs contaminating aquatic environments.
- Researchers in Sweden exposed juvenile Atlantic salmon in Lake Vättern to environmentally relevant levels of cocaine and benzoylecgonine, discovering that these substances altered fish behavior by increasing movement and dispersal distances.
- Cocaine and its metabolites enter waterways primarily through wastewater discharge, as treatment plants are not designed to fully remove these compounds, leading to widespread contamination detected worldwide.
- Behavioral changes in fish caused by these pollutants could impact energy use, habitat quality, and predation risk, potentially affecting population dynamics and ecosystem health, especially for vulnerable species like Atlantic salmon.
- The study revealed that benzoylecgonine had a stronger behavioral effect than cocaine itself, suggesting current environmental risk assessments may underestimate the ecological risks posed by drug metabolites in aquatic systems.
