Overview
- The new field study reports that salmon exposed to cocaine swam 1.9 times farther per week, and those exposed to its main metabolite covered an extra 12.3 kilometers.
- Scientists captured roughly 100 wild Atlantic salmon in Sweden’s Lake Vättern, exposed them to cocaine and benzoylecgonine, then tracked how far they moved.
- The authors say drug and medicine residues in waterways pose a growing risk to biodiversity and call for better wastewater treatment and monitoring.
- Wastewater checks across Europe, including a March 2026 Belgian analysis, found rising traces of cocaine, ecstasy, and amphetamines compared with 2023.
- The United Nations estimates about 25 million people used cocaine in 2023, which helps explain why residues linked to human use now turn up in rivers.