Public warned 'do not eat' after prawns exposed to radioactive substance

The US Food and Drug Administration (FDA) warned the public not to eat Walmart's Great Value label frozen shrimp after it was exposed to a dangerous isotope.

The sample of the seafood tested positive for the radioactive substance but it "did not enter the US commerce", the FDA said.

Shoppers in the 13 states where the shrimp was available have been told to throw away the products from three batches.

One shipment tested positive for Caesium-137 - the radioactive form of the periodic element Caesium.

"The health and safety of our customers is always a top priority," a Walmart spokesperson said.

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"We have issued a sales restriction and removed this product from our impacted stores. We are working with the supplier to investigate," they told the BBC.

Consumers who bought the recalled products can visit any Walmart location for a full refund, the spokesperson said.

The recalled shrimp was sold at Walmart locations in:

• Alabama
• Arkansas
• Florida
• Georgia
• Kentucky
• Louisiana
• Missouri
• Mississippi
• Ohio
• Oklahoma
• Pennsylvania
• Texas
• West Virginia

The shrimp came from an Indonesian supplier.

The firm has since had a number of shipping containers denied entry to the US, the FDA reported.

The radioactive substance was not enough to pose acute harm to customers, but exposure over time could pose an elevated risk of cancer by damaging living cells in the body.

Caesium-137 is made through nuclear reactions. The chemical is present, across the world, in trace amounts within soil, food and air.

The FDA concluded no Caesium-137 had been detected in the other products it tested, but cautioned this did not rule out contamination.