A widening seafood safety scare has prompted federal officials to expand a nationwide shrimp recall for the second time in a week. Walmart’s popular Great Value brand to the growing list of products pulled from store shelves over concerns about possible radioactive contamination.

The Food and Drug Administration issues a second recall on frozen shrimp after potential exposure to radioactive material.

The potential Cesium-137 contamination has prompted the recall of multiple brands sold at retailers across the nation.