General Discussion

Two examples from Wikipedia of fatalities resulting from mis-use of devices containing CS-137 .

In the Goiânia accident of 1987, an improperly disposed of radiation therapy system from an abandoned clinic in Goiânia, Brazil, was removed, then cracked to be sold in junkyards. The glowing caesium salt was then to be sold to curious, unadvised buyers.[35] This led to four confirmed deaths and several serious injuries from radiation contamination.[36][37]

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The 1994 Tammiku incident involved the theft of radioactive material from a nuclear waste storage facility in Männiku, Saku Parish, Harju County, Estonia. Three brothers, unaware of the facility's nature, broke into a shed while scavenging for scrap metal. One of the brothers received a 4,000 rad whole-body dose from a caesium-137 source that had been released from a damaged container, succumbing to radiation poisoning 12 days later.