Invisible threats – ocean acidification, chemical and microplastics pollution and oxygen depletion – are changing the marine environment and placing coastal resources at risk. Understanding their long-term impact requires a globally coordinated scientific response.
To address this, the International Atomic Energy Agency (IAEA) launched a four-year Coordinated Research Project called ‘Applied Radioecological Tracers to Assess Coastal and Marine Ecosystem Health’. It intends to support the development, improvement and application of nuclear techniques to assess environmental damage and better understand associated risks.
IAEA used radioecological tracers – natural and fabricated substances containing small amounts of radioactive isotopes – to track the movement, exposure pathways and accumulation of contaminants in marine food webs.
Using advanced techniques across different regions, scientists were able to show how ecosystems respond to external pressures and how marine organisms are affected by ocean change. It revealed how ocean acidification influences mercury metabolism in marine life.
Marine Plastic Pollution
Findings showed that changing water chemistry affects how species like cuttlefish absorb and retain contaminants such as organic and inorganic mercury during early life stages. This highlights a direct link between ocean acidification and seafood safety.
Jana Friedrich, Head of the IAEA Radioecology Laboratory in Monaco, said by providing countries with insights on contaminants in marine organisms using radiotracer techniques, they are enhancing the global scientific community’s capacity to monitor contaminant pathways in the marine food web. Scientists are providing the rigorous data needed to inform environmental protection strategies worldwide.
They looked into the growing global threat of marine plastic pollution, revealing previously unquantified complex ecological interactions, and investigated how floating plastic litter can act as an artificial vector, transporting toxic microalgae and harmful biotoxins across the ocean.
Also Read: WaiV Robotics Steps into U.S. Market, Maritime UAV for Offshore Industry
Researchers used microscopic and advanced analytical techniques to identify high-risk areas globally. They established that floating microplastics can facilitate the dispersal of toxic benthic algae from tropical regions to higher latitudes.
This bio-colonization means that dangerous toxins can enter marine food chains and reach marine animals in open waters that would otherwise never encounter them, presenting a novel threat to both marine life and human consumers of seafood.
Impact on Marine Life
Luiz Mafra, Jr., a researcher at the Federal University of Paraná in Brazil, explained that the collaborative work made them rethink the impact of marine litter. Data shows that more than one third of coastal waters globally are at risk of plastics acting as vectors for harmful algal blooms, creating a pressing need for integrated monitoring.
Moreover, the project has generated critical information that can support several major international environmental frameworks, including the Minamata Convention on Mercury. It identified new areas for future collaboration. Participating scientists agreed to produce a joint perspective paper on polonium, a powerful natural radiotracer in seawater. The forthcoming publication aims to broaden awareness among policymakers and non-experts about polonium’s potential to map deep-sea vulnerability and organic carbon cycling.