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The Goiânia accident was an incident of radioactive contamination that killed several individuals and injured many others.
On September 13, 1987 an old radiation source was stolen from an abandoned hospital in the Brazilian city of Goiânia and subsequently handled by several people who suffered serious contamination, resulting in several deaths. The incident is considered one of the worst accidents in world history to involve the improper handling of radioactive waste.
The object was a small, highly radioactive rod of caesium chloride (a caesium salt; it was made using a radioactive isotope of caesium) encased in a shielding canister made of lead and steel with an iridium window. It was made and used as a radiation source for radiation therapy when the hospital was still in operation. When the building was abandoned in 1984, the source was left behind. Over the following years, many squatters and scavengers entered the building to look for shelter and useful or interesting items. Eventually, in 1987, two people came across the radiation source and took it with them.
The two attempted to open the casing, but were unable to. However, they did manage to break the iridium window, which allowed them to see the cesium rod emitting a deep blue light. The light was caused by fluorescence of the chloride ions when stimulated by the strong gamma rays emitted by the cesium. They sold the object to a junkyard owner who intended to make a ring for his wife out of the strange and beautiful blue material. The invisible gamma rays severely irradiated the two people who initially found it—one later had to have an arm amputated.
The sale to the junkyard owner led to many more people becoming contaminated:
- Junkyard workers hammered open the lead casing. Two of them died later of radiation poisoning.
- A brother of the junk dealer scraped dust off the rod, spreading some of it on the floor of his house. His six-year-old daughter, Leide dos Neves Ferreira, later ate on this floor, absorbing some of the radioactive material. She died a month later, and was buried in a lead coffin.
- Several people who visited the home came into contact with the dust and spread it around the local neighbourhood and to other towns nearby.
- Another brother of the junkyard owner used the dust to paint a blue cross on his skin. He also contaminated the animals at his farm, several of which died.
The junkyard owner's wife, Maria Gabriela Ferreira, was the first to notice that many people around her had become severely sick all at the same time. She first suspected the culprit was a beverage they had shared, but an analysis of the juice showed nothing untoward.
On September 28 (15 days after the source was found) Maria finally suspected the blue rod to be the cause. She took it to a hospital, and the physician there rightly suspected that it was radioactive. Two local physicists confirmed its radioactivity using scintillation counters.
She died a month later from the effects of the radiation, though she may have saved the lives of many others by finally disposing of the dangerous but innocent looking object.
Afterwards, about 100,000 people were examined for radioactive contamination; 244 were found to have significant levels of radioactive material in their body. It is unclear how many were exposed to the radiation itself. Of those contaminated, 10 people needed intensive care for radiation poisoning. It seems reasonable to assume that considerably more people died than are clearly accounted for. In light of the deaths caused, the three doctors who had owned and run the hospital were charged with criminal neglect.
In summary, the main cause of this incident was clearly the severe negligence of the former hospital management who left behind and forgot about such a dangerous item. The accident clearly demonstrated the importance of keeping an inventory and monitoring of all strong radiation sources by public authorities. This is required by law in Canada, the United States, and many other countries.
Recently, the spread of the contamination in this case has also been used to estimate the effect of a radiological weapon.