Researchers found seafood such as mussels, paua and oysters contained concentrated levels of radiation.

Those at particular risk were sub-populations for whom fish consumption was culturally important and those relying of fishing and shellfish collection to feed their families, the study’s authors said in an article released on Friday.

“Seafood has importance to the New Zealand population as a source of nutrition consumed in considerable amounts by some sectors of the community,” they said.

“Chemical contaminants in seafood can therefore lead to significant health burdens to the population and it is an important public health function to identify the contaminants of concern and characterise their exposure.”

Researchers measured levels of radioactive caesium…