Cs-137 contaminated shrimp? What we know
Media outlets have been abuzz this week with news of cesium-137 contamination in Great Value (Walmart’s private-label brand) frozen shrimp, according to a Food and Drug Administration report.
The amount of Cs-137 in the bags of shrimp was more than 17 times lower than the FDA’s derived intervention level for the radioactive isotope and as such “would not pose an acute hazard to consumers,” according to the report. The contaminated shrimp was barred from entering the country, but even so, the FDA is advising Walmart and consumers toss other Great Value shrimp.
The details: According to the FDA, the products came from an Indonesian food company called PT. (equivalent to an LLC) Bahari Makmur Sejati, which also operates under the name BMS Foods. The shrimp traveled through U.S. ports in Los Angeles, Houston, Savannah, and Miami, where the Cs-137 was detected by U.S. Customs and Border Protection, which in turn alerted the FDA.
BMS’s shrimp is reportedly sold at Walmarts in Alabama, Arkansas, Florida, Georgia, Kentucky, Louisiana, Missouri, Ohio, Oklahoma, Pennsylvania, Texas, and West Virginia.
All contaminated products were denied entry into the country, and there have been no reports of Cs-137-contaminated products entering commerce. However, Walmart has received shrimp that was imported from BMS Foods after the first detection of Cs-137 that did not set off alerts. This subset of shrimp is the group that the FDA recommends disposing. Here are the affected product details:
| Product Name | Best By Date | Lot Code |
| Frozen Raw Ez Peel Tail-On Farm-Raised White Vannamei Shrimp (2 lb bag) | 3/15/2027 | 8005540-1 |
| Frozen Raw Ez Peel Tail-On Farm-Raised White Vannamei Shrimp (2 lb bag) | 3/15/2027 | 8005538-1 |
| Frozen Raw Ez Peel Tail-On Farm-Raised White Vannamei Shrimp (2 lb bag) | 3/15/2027 | 8005539-1 |
Nuclear context: The FDA’s derived intervention level for Cs-137 contamination is 1,200 Bq/kg. Laboratory testing confirmed that the BMS shrimp contained an activity concentration significantly below figure: 68.48 Bq/kg +/− 8.25 Bq/k. To put that number further into context, 68 Bq/kg is similar to the activity concentration in bananas.
The key difference is that the radioactivity in bananas comes from naturally occurring potassium-40, while Cs-137 is a manmade byproduct of nuclear fission. While this level of radiation is not harmful to humans, the discovery triggered a response because it is unusual to see this concentration of Cs-137 in shrimp.
Cs-137 is detectable in shrimp originating from the Pacific Ocean due to past nuclear testing and accidents, but the routine detection levels are roughly 100 times lower than the BMS shrimp.
A group of health physicists from the American Nuclear Society echoed these sentiments, saying “It is important to note that the radioactive activity concentration in these shrimps is similar to naturally occurring concentrations in bananas. The FDA triggered this response as it is abnormal to see Cs-137 in frozen shrimp at these levels, and it warrants further investigation.”
