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Sunday, 27 October 2019

The Goiânia Radiological Accident

teletherapy machine
A radiation therapy unit in a hospital.  
Radioactive isotopes have a very niche use in medicine, where they are used both in diagnosis as well as in treatment. The most widely used is radiotherapy, where a concentrated dose of radiation is directed towards a malignant tumor or group of cancerous cells to kill them. Sometimes tiny doses of radioactive materials called radiotracers are injected into the bloodstream of a patient, and the gamma rays they give off are imaged with the help of a special camera to create images of the inside of the patient’s body.
Hospitals and clinics where such procedures are available has strict protocols regarding the handling of these devices. When such a hospital or institution closes and has to be demolished, the wrecking company has to be informed so that that the instruments can be safely dismantled and the hazardous materials moved to a secured location. Failing to do so can lead to tragedy. Such an incident happened in the Brazilian city of Goiânia in 1987.
Two years prior to the incident, a private radiotherapy institute in Goiânia, relocated to a new premise leaving behind many old hospital machines and supplies. Among them was a teletherapy unit containing 93 grams of highly radioactive caesium chloride, a salt of cesium-137, a radioactive isotope with a half life of 30 years. The salt was encased in a shielded canister made of lead and steel.
At that time, the radiotherapy institute and the owners of the premise was locked in a court battle regarding the ownership of the abandoned site, and the court forbade the removal of any objects from the site by either parties before a decision was ruled. The owners of the institute wrote to the National Nuclear Energy Commission (CNEN), warning them about the danger of keeping a teletherapy unit at an abandoned site. The court appointed a guard on the site, but it was not enough to keep out scrap hunters.
On September 13, 1987, taking advantage of the absence of the guard, Roberto dos Santos Alves and Wagner Mota Pereira stole into the partially demolished facility and took off with the radioactive source assembly thinking the shiny stainless steel object could be valuable. The two went to Alve’s home where they began dismantling the equipment. That same evening, both Alves and Pereira began to vomit, which they assumed was due to something they had eaten. The following day Pereira began to experience diarrhea and dizziness, and his left hand began to swell. He also developed a burn on his hand in the same size and shape as the aperture of the radioactive device. Pereira went to a local clinic, but the doctors, unaware of the signs of radioactive poisoning, dismissed his condition as an allergic reaction and just told him to go home and take rest.
Alves, who was in better shape at that time, continued to work at the assembly, determined to break it apart. He eventually managed to puncture a hole through the protective casing with a screwdriver, and scooped out some of the cesium. Thinking it might be gunpowder, he attempted to light it but the powder won’t burn. Alves’ persistence paid off, and six days after the theft, he was able to completely remove the source wheel from the casing. The same day, he sold the source to a nearby scrapyard.
That night, Devair Alves Ferreira, the owner of the scrapyard, went into the garage where the pieces had been placed and noticed a blue glow emanating from the source capsule. This glow was caused by the radiation ionizing the air molecules. Ferreira though it looked pretty, and took the capsule into the house to show his family. Over the next three days, many neighbours, relatives and Ferreira’s friends came to see the wonderful light-emitting capsule. Ferreira also freed up several grains of the glowing material and distributed them among his friends and relatives. Some rubbed them on their skin like glitter during carnival times. Ferreira’s six-year-old niece spread some of it on the concrete floor, and later ate a sandwich while sitting on this floor.
On September 21, Ferreira’s 37-year-old wife fell ill with vomiting and diarrhea. She went to a hospital for diagnosis, but like Pereira, she was told she had an allergic reaction to something she had eaten and sent her home to rest. Meanwhile, Devair Ferreira sold the scrap metal to a second scrapyard.
By this time a significant number of people were physically ill. Ferreira’s wife, Gabriela Maria Ferreira, suspected that the glowing powder from the source assembly was causing the sickness. She went to the second scrapyard, where her husband sold the capsule, and convinced the owner to put the remnants of the source assembly in a bag. She then took the bag to a hospital and deposited it on the desk of the doctors, saying that this thing was “killing her family”.
The doctors were unsure but they were worried enough to take the bag out of the hospital building and put it in the backyard.
Goiânia Radiological Accident
Chronology of events.
Gabriela Maria Ferreira was initially diagnosed as having contracted a tropical disease, but one of the doctors saw the skin lesions and knew it was due to radiation. From there the pace of the incidents quickened as the seriousness was appreciated. Authorities in Goiania mobilized police, fire and civil defence forces, and a temporary screening camp was setup inside an Olympic stadium. Some 250 people were found to have significant levels of radioactive material in or on their body. At least twenty showed signs of radiation sickness and required treatment.
The Goiânia incident left four people dead—Devair Ferreira’s wife, two of his employees and his six-year-old niece Leide das Neves Ferreira, who sat on the floor eating pieces of cesium-137 along with her sandwich. Everyone suffered multiple organ damage, internal bleeding, hair loss and external scarring.
The original two players of this egregious incident, Roberto dos Santos Alves and Wagner Mota Pereira, the ones who stole the radioactive source, miraculously survived but had to undergo amputation of their arms. Their later fate is not known.
Devair Ferreira also survived despite receiving a nearly fatal dose of radiation. He died in 1994 of cirrhosis aggravated by depression and binge drinking.
Goiânia Radiological Accident

Clockwise from top-left: (1) The derelict premises of the Institute Goiano de Radioterapia. (2) Demolition of the house of Roberto Alves. (3) Preparing to demolish the house of Devair Ferreira’s neighbors. (4) Boxes and drums of waste stacked and covered at the temporary storage site. 

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