Ref - International Atomic Energy Agency

On the 13th of September 1987, a shielded, strongly radioactive 137caesium source (50.9 TBq, 1375 Ci, at the time of the accident) was removed from its protective housing in a teletherapy machine in an abandoned clinic in Goiania, Brazil, and subsequently opened. Consequently, many people incurred large doses of radiation, due to both external and internal exposure. Four of the casualties ... ................
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