What effect is cocaine pollution having on young Atlantic salmon?

Environment
21 Apr 2026 • 9:52 PM MYT
The Independent
The Independent

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What effect is cocaine pollution having on young Atlantic salmon?

  • A new study has found that cocaine pollution is changing the behaviour of juvenile Atlantic salmon in the wild, causing them to swim further and disperse more widely.
  • This research, conducted by Griffith University, is the first to demonstrate the effects of cocaine contamination on fish behaviour in natural environments.
  • Tracking over a hundred juvenile salmon in Sweden's Lake Vättern, the study revealed that fish exposed to benzoylecgonine, a cocaine derivative, swam twice as far and dispersed up to 12.3km further.
  • Cocaine and its metabolites are increasingly present in rivers and lakes globally, entering waterways primarily through wastewater systems that cannot fully remove them.
  • Researchers warn that these altered movement patterns could significantly impact ecosystems, though they confirm there is no risk to humans consuming fish.

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