"The American Nuclear Society explained that the Cs-137 contamination likely began as cesium chloride, which, once smelted, would rise above its boiling point and enter the atmosphere in gaseous form, exposing BMS Foods' facility to the radioactive isotope."
"Additionally, the Indonesian government discovered 14 containers of scraps from the Philippines, which are contaminated by Cs-137, in Tanjung Priok Port, North Jakarta. This finding suggests that the radioactive contamination may also originate to containers used in export, as well as from the Cikande environment."
This explanation does not apply to the shipment of cloves that were also found to have Cesium-137 contamination.
https://www.food-safety.com/articles/10757-indonesian-officials-find-cause-of-cs-137-contamination-behind-radioactive-shrimp
Indonesian Officials Find Cause of Cs-137 Contamination Behind Radioactive Shrimp
October 6, 2025
Since August, the U.S. Food and Drug Administration (FDA) has alerted the public to detections of radioactive isotope Cesium-137 (Cs-137) in shipments of shrimp sold at Walmart and other major retailers, and clove spices that did not enter commerce, imported from Indonesia. These detections led FDA to exercise for the first time a Congressional authorized power to require import certification for those commodities from certain regions of the country.