How Did Walmart Frozen Shrimp Became Contaminated With Radioactive Material?

As you've probably already heard, the Food and Drug Administration has issued a recall warning for bags of frozen shrimp sold under Walmart's "Great Value" brand over concerns about radioactive contamination.

As the FDA explained in a statement, shipping containers and frozen shrimp parcels used by the Indonesia-based Walmart contractor BMS Foods tested positive for Cesium-137, a radioactive isotope and byproduct of nuclear fission.

Though only a single shipment of the shrimp was found to contain Cs-137, as the isotope is abbreviated, poisoning from it is nasty stuff. As the Centers for Disease Control and Prevention explains, coming into contact with it can cause "burns, acute radiation sickness, and even death."

From the start, details about the Cs-137 contamination have been bizarre.