Abstract <p>A pilot study on the levels of Polonium-210 (²¹⁰Po) and Lead-210 (²¹⁰Pb) in various marine fish species along the Kochi (Cochin) coast was conducted to evaluate the potential risks to human health. The findings revealed that ²¹⁰Po concentrations were generally higher than ²¹⁰Pb concentrations across the studied species. Fish inhabiting pelagic zones and those that primarily feed on plankton exhibited the highest levels of radionuclides and bioaccumulation factors. In contrast, certain predatory fish and those living in benthic environments showed moderate radionuclide concentrations in their muscles. The annual committed effective doses (ACEDs) for both ²¹⁰Po and ²¹⁰Pb were found to fall within the minimum ICRP safety limit of 1 mSv y⁻¹, indicating that the consumption of these fish is unlikely to pose significant health risks. The accumulation patterns of radionuclides are influenced by a combination of factors, including environmental conditions, feeding habits, taxonomy, and local geological context. These findings highlight the importance of considering ecological and environmental variables when assessing radionuclide contamination in marine ecosystems and its implications for human health.</p> Research highlights <p><UnorderedList Mark="Bullet"> <ItemContent> <p>The ²¹⁰Po and ²¹⁰Pb levels varied greatly across fish species based on diet.</p> </ItemContent> <ItemContent> <p>Pelagic planktivores showed high ²¹⁰Po BSFs and elevated ²¹⁰Po/²¹⁰Pb ratios.</p> </ItemContent> <ItemContent> <p>All species’ ACED values remained well below the minimum safe value of 1 mSv y⁻¹.</p> </ItemContent> <ItemContent> <p>²¹⁰Po levels exceeded the global averages but matched the global accumulation trends.</p> </ItemContent> <ItemContent> <p>Fish consumption is safe, but monitoring is vital for ecological and public health.</p> </ItemContent> </UnorderedList></p>