The US Food and Drug Administration on Tuesday urged the public not to eat certain bags of frozen raw shrimp sold at Walmart, citing concerns about unsanitary conditions and radioactive contamination found in shipments from the same supplier.

Some packages of Great Value frozen shrimp sold at Walmart are at risk for potential for Cesium-137 contamination, the FDA says.

The risk from the recalled shrimp is "quite low," said Donald Schaffner, a food safety expert at Rutgers University. Cesium-137 is a byproduct of nuclear reactions.