The U.S. Food and Drug Administration (FDA) warned consumers Tuesday to steer clear of certain frozen shrimp products sold under Walmart’s Great Value brand, noting that some shipments were reportedly contaminated with a radioactive substance.

The shrimp in question, shipped from the PT. Bahari Makmur Sejati company in Indonesia, are under investigation for potentially containing Cesium-137 (Cs-137) — a man-made substance created through nuclear reactions, the agency said in a statement Tuesday.

U.S. Customs and Border Protection (CPB) first detected Cs-137 in shipments at four different U.S. ports, and the FDA collected samples from the product confirming the presence of Cs-137 in one sample of breaded shrimp, according to the statement.

“FDA has concluded that the level detected in the breaded shrimp sample could represent a potential health concern for those exposed to this level of Cs-137 from consumption of the shrimp over an extended period of time combined with radiation that exists in the environment and from other sources such as medical procedures,” the FDA’s statement reads.

The contaminated shipment “did not enter U.S. commerce,” and the agency said it “continues to coordinate with CBP to prevent any contaminated products from reaching consumers.” (RELATED: EXCLUSIVE: Americans Can Now See If Companies Are Actually Making Good On Food Dye Pledge)

“Although testing to date has not confirmed the presence of contamination in any product in commerce, the product appears to have been prepared, packed, or held under insanitary conditions whereby it may have become contaminated with Cs-137 and may pose a safety concern,” the FDA said in its Tuesday advisory.

Consumers, distributors, and retailers should not eat, serve or sell impacted lots of Great Value raw frozen shrimp sold at Walmart.

For more information on lot codes, production dates and actions you should take read FDA’s advisory. https://t.co/eO87TdXbtx pic.twitter.com/vU1Brqg89Q

— U.S. FDA Human Foods Program (@FDAfood) August 19, 2025

The FDA noted that testing to date has not found other products in commerce to be contaminated, and it is working to prevent other potentially polluted products from entering the country.

The agency also said it is working to trace all products processed by PT. Bahari Makmur Sejati to “gather as much information about them as possible and take action as appropriate.”

The FDA said it urged Walmart to recall the product, and the agency advised consumers to throw out any product of the impacted lots.

“If you have recently purchased raw frozen shrimp from Walmart that matches this description, throw it away,” the FDA’s statement read. “Do not eat or serve this product.”

Walmart confirmed to the Daily Caller that the company recalled the product from impacted stores, adding that it will offer a refund to any customers with the product in their possession.

“The health and safety of our customers is always a top priority,” a Walmart spokesperson told the Caller. “We have issued a sales restriction and removed this product from our impacted stores. We are working with the supplier to investigate.”