Climate change may release large amounts of stored mercury into the ocean as rising temperatures and thawing permafrost destabilise long-buried pollution, raising health risks linked to seafood consumption.
The warning comes from researcher Michael Bank of the Institute of Marine Research in Norway, who advises the UN on chemicals and climate.
Old Pollution Returns
Permafrost in regions such as Svalbard is melting rapidly, freeing mercury that has been trapped for decades or even centuries. Warmer oceans may also trigger releases.
This “inherited mercury” differs from modern industrial emissions and can leak during environmental disruptions, including heatwaves, wildfires, and other extreme weather events.
Researchers say the most dangerous form is methylmercury. This potent nerve toxin enters marine food chains through algae and fish before reaching humans.
Seafood is already the largest source of methylmercury in human diets, increasing concern that more of the toxin could end up on dinner plates.
Marine Ecosystems at Higher Risk
Ocean ecosystems may be particularly vulnerable because mercury levels there are already high. Coastal waters, algal bloom zones, and man-made wetlands are considered hotspots at risk of further contamination.
Scientists propose monitoring sensitive areas using satellites, drones and AI-based data analysis. They also call for better tools to trace mercury sources and measure releases.
Bank warns this is essential to protect marine life, biodiversity, seafood safety and public health.
The research forms part of the EU-funded MERFISH project, which studies how mercury moves from fish to humans and the role of selenium in detoxification.