| Goiânia accident | |
| Location: | Goiânia, Goiás, Brazil |
| Type: | Radiation accident |
| Cause: | Radiation source left unsecured by authorities |
| Participants: |
|
| Outcome: | INES Level 5 (accident with wider consequences) |
| Reported Deaths: | 4 |
| Reported Injuries: | 249 contaminated |
The Goiânia accident pronounced as /pt/ was a radioactive contamination accident that occurred on September 13, 1987, in Goiânia, Goiás, Brazil, after an unsecured radiotherapy source was stolen from an abandoned hospital site in the city. It was subsequently handled by many people, resulting in four deaths. About 112,000 people were examined for radioactive contamination and 249 of them were found to have been contaminated.[1] [2]
In the consequent cleanup operation, topsoil had to be removed from several sites, and several houses were demolished. All the objects from within those houses, including personal possessions, were seized and incinerated. Time magazine has identified the accident as one of the world's "worst nuclear disasters" and the International Atomic Energy Agency (IAEA) called it "one of the world's worst radiological incidents".[3] [4]
The radiation source in the Goiânia accident was a small capsule containing about of highly radioactive caesium chloride (a caesium salt made with a radioisotope, caesium-137) encased in a shielding canister made of lead and steel. The source was positioned in a container of the wheel type, where the wheel turns inside the casing to move the source between the storage and irradiation positions.[1]
| Goiânia source | (TBq) | |
|---|---|---|
| 1971 | ||
| 1987 | ||
| Recovered | ||
| Unrecovered (c. 1987) | ||
| Unrecovered (c. 2016) | ||
| Smoke detector | ||
The activity of the source was 74 terabecquerels (TBq) in 1971. The International Atomic Energy Agency (IAEA) describes the container as an "international standard capsule". It was 51 millimeters (2 inches) in diameter and 48 mm (1.8 inches) long. The specific activity of the active solid was about 814 TBq·kg−1 of caesium-137, an isotope whose half life is 30 years. The dose rate at one meter from the source was 4.56 grays per hour (456 rad·h−1). While the serial number of the device was unknown, hindering the ability to verify its identity, the device was thought to have been made in the U.S. at Oak Ridge National Laboratory as a radiation source for radiation therapy at the Goiânia hospital.[1]
The IAEA states that the source contained 1375Ci when it was taken and that about 44TBq of contamination had been recovered during the cleanup operation. This means that 7TBq remained in the environment; it would have decayed to about 3.5TBq by 2016.
The Portuguese: Instituto Goiano de Radioterapia (IGR), a private radiotherapy institute in Goiânia,[1] was 1km (01miles) northwest of Portuguese: Praça Cívica|italic=no, the administrative center of the city. When IGR moved to its new premises in 1985, it left behind a caesium-137-based teletherapy unit purchased in 1977. The fate of the abandoned site was disputed in court between IGR and the Society of Saint Vincent de Paul, then owner of the premises.[5] On September 11, 1986, the Court of Goiás stated it had knowledge of the abandoned radioactive material in the building.[5]
Four months before the theft, on May 4, 1987, Saura Taniguti, then director of Ipasgo, the institute of insurance for civil servants, used police force to prevent one of the owners of IGR, Carlos Figueiredo Bezerril, from removing the radioactive material that had been left behind.[5] Figueiredo then warned the president of Ipasgo, Lício Teixeira Borges, that he should take responsibility "for what would happen with the caesium bomb".[5] The Court of Goiás posted a security guard to protect the site.[6] Meanwhile, the owners of IGR wrote several letters to the National Nuclear Energy Commission (CNEN), warning them about the danger of keeping a teletherapy unit at an abandoned site, but they could not remove the equipment on their own once a court order prevented them from doing so.[5] [6]
On September 13, 1987, the guard tasked with protecting the site did not show up for work. Roberto dos Santos Alves and Wagner Mota Pereira illegally entered the partially demolished IGR site. They partially disassembled the teletherapy unit and placed the source assembly in a wheelbarrow to later take to Roberto's home. They thought they might get some scrap value for the unit. They began dismantling the equipment. That same evening, they both began to vomit due to radiation sickness. The following day, Pereira began to experience diarrhea and dizziness, and his left hand began to swell. He later developed a burn on his hand in the same size and shape as the aperture, and he underwent partial amputation of several fingers.[7]
On September 15, Pereira visited a local clinic, where he was diagnosed with a foodborne illness; he was told to return home and rest.[1] Roberto, however, continued with his efforts to dismantle the equipment and eventually freed the caesium capsule from its protective rotating head. His prolonged exposure to the radioactive material led to his right forearm becoming ulcerated, requiring amputation on October 14.[8]
On September 16, Roberto punctured the capsule's aperture window with a screwdriver, allowing him to see a deep blue light coming from the tiny opening he had created. He inserted the screwdriver and successfully scooped out some of the glowing substance. Thinking it was perhaps a type of gunpowder, he tried to light it, but the powder would not ignite.
The exact mechanism by which the blue light was generated was not known at the time the IAEA report of the incident was written, though it was thought to be either ionized air glow, fluorescence, or Cherenkov radiation associated with the absorption of moisture by the source; a similar blue light was observed in 1988 at Oak Ridge National Laboratory in the United States during the disencapsulation of a caesium-137 source.
On September 18, Roberto sold the items to a nearby scrapyard. That night, Devair Alves Ferreira, the owner of the scrapyard, noticed the blue glow from the punctured capsule. Thinking the capsule's contents were valuable or supernatural, he immediately brought it into his house. Over the next three days, he invited friends and family to view the strange glowing powder.
On September 21, at the scrapyard, one of Ferreira's friends (identified as "EF1" in the IAEA report) freed several rice-sized grains of the glowing material from the capsule using a screwdriver. Ferreira began to share some of them with various friends and family members. That same day, his wife, 37-year-old Maria Gabriela Ferreira, began to fall ill. On September 25, 1987, Devair Ferreira sold the scrap metal to a third scrapyard.
The day before the sale to the third scrapyard, on September 24, Ivo, Devair's brother, successfully scraped some additional dust out of the source and took it to his house a short distance away. There he spread some of it on the concrete floor. His six-year-old daughter, Leide das Neves Ferreira, later ate an egg sandwich while sitting on the floor. She was also fascinated by the blue glow of the powder, applying it to her body and showing it off to her mother. The egg sandwich was also exposed to dust from the powder; Leide absorbed 1.0 GBq and received a total dose of 6.0 Gy, a fatal dose for which medical intervention was ineffective.[9] [10] [11]
Maria Gabriela Ferreira had been the first to notice that many people around her had become severely ill at the same time.[12] On September 28, 1987 – fifteen days after the item was found – she reclaimed the materials from the rival scrapyard and transported them to a hospital.
In the morning of September 29, a visiting medical physicist[13] used a scintillation counter to confirm the presence of radioactivity and persuaded the authorities to take immediate action. The city, state, and national governments were all aware of the incident by the end of the day.
News of the radiation incident was broadcast on local, national, and international media. Within days, nearly 130,000 people in Goiânia flooded local hospitals, concerned that they might have been exposed. Of those, 249 were indeed found to be contaminated – some with radioactive residue still on their skin – through the use of Geiger counters. Eventually, twenty people showed signs of radiation sickness and required treatment.
Ages in years are given, with dosages listed in grays (Gy).
Devair Ferreira survived despite receiving 7 Gy of radiation. He died in 1994 of cirrhosis aggravated by depression and binge drinking.[17] Ivo Ferreira died of emphysema in 2003.[18]
The outcomes for the 46 most contaminated people are shown in the bar chart below. Several people survived high doses of radiation. This is thought in some cases to be because the dose was fractionated.[1] Given time, the body's repair mechanisms will reverse cell damage caused by radiation.[19] If the dose is spread over a long time period, these mechanisms can mitigate the effects of radiation poisoning.[19]
Afterwards, about 112,000 people were examined for radioactive contamination; 249 were found to have significant levels of radioactive material in or on their body. Of this group, 129 people had internal contamination. The majority of the internally contaminated people only suffered small doses (corresponding to less than about 1 in 200 excess risk of developing cancer later in life[20]). A thousand people were identified as having suffered a dose which was greater than one year of background radiation; it is thought that 97% of these people had a dose of between 10 and 200 mSv (between 1 in 1,000 and 1 in 50 excess risk of developing cancer as a result).
In 2007, the Oswaldo Cruz Foundation determined that the rate of caesium-137 related diseases are the same in Goiânia accident survivors as they are in the population at large. Nevertheless, compensation is still distributed to survivors, who suffer radiation-related prejudices in everyday life.[21]
In addition to a public civil action for damages to the environment that was brought in September 1995 by the Federal Public Prosecution Service (Department of Justice), together with the State of Goiás’ Public Prosecution Service, before the 8th Federal Court of Goiânia, legal proceedings were also brought against the Federal Union; the National Nuclear Energy Commission; the State of Goiás (through its Health Department); the Social Security Institute for Civil Servants in the State of Goiás – IPASGO, which at the time of the accident was the private owner of the land where the IGR was located; the four medical doctors who owned IGR; and the clinic’sphysicist, who was also the supervisor.
On March 17, 2000, the 8th Federal Court of Goiás ordered the defendants to pay compensation of R$1.3 million (near US$750,000) to the Defence of the Diffused Rights Fund, a federal fund for the compensation of damage to the environment, consumers, property and rights of artistic, historic, or cultural value and other collective rights.
In his sentence, the Judge excluded the state of Goiás and the Federal Union from the paymentof compensation.
The CNEN was ordered to pay compensation of R$1 million, to guarantee medical and psychological treatment for the direct and indirect victims of the accident and their descendants down to the third generation, to provide transportation to medical exams for the most serious victims, and was responsible for the medical follow-up for the people of Abadia de Goiás city.
The Social Security Institute for Civil Servants in the State of Goiás, IPASGO, was ordered topay a fine of R$100 000, plus interest as of 13 September 1987, the date of removal of the Caesium 137 capsule.
As the accidents occurred before the promulgation of the Federal Constitution of 1988 and because the substance was acquired by the clinic and not by the individual owners, the court could not declare the owners of IGR liable. However, one of the owners was fined R$100 000 because he was found liable for the abandoned state of the IGR building where the Caesium source was kept, including the removal of gates, windows, timberwork and the roof in May 1987.
The clinic’s physicist was also fined R$100 000 because he was the technician responsible for the controlof the medical manipulation of the radiological device.
Although the two thieves were not included as defendants in the public civil suit, the judgement of the court found them directly responsible for the accident. If they had been arraigned as defendants, they certainly would have been convicted, as their actions led to strict (no-fault) liability. However, in terms of criminal intent, they were not aware of the seriousness of their actions in removing the Caesium source from its location, and they had no knowledge of the dangers of the radiological device; moreover, there was no danger sign erected in the abandoned clinic in order to ward off intruders.[22]
Topsoil had to be removed from several sites, and several houses were demolished. All the objects from within those houses were removed and examined. Those that were found to be free of radioactivity were wrapped in plastic bags, while those that were contaminated were either decontaminated or disposed of as waste. In industry, the choice between decontaminating or disposing objects is based on only the economic value of the object and the ease of decontamination. In this case, the IAEA recognized that to reduce the psychological impact of the event, greater effort should have been taken to clean up items of personal value, such as jewelry and photographs. It is not clear from the IAEA report to what degree this was practised.
After the houses were emptied, vacuum cleaners were used to remove dust, and plumbing was examined for radioactivity. Painted surfaces could be scraped, while floors were treated with acid and Prussian blue mixtures. Roofs were vacuumed and hosed, but two houses had to have their roofs removed. The waste from the cleanup was moved out of the city to a remote place for storage. Aeroradiometric operations were undertaken by low-altitude survey, which was carried out over Goiânia. The radiometric equipment and materials available at the IRD[23] were quickly transported and mounted on a Eurocopter AS350 Écureuil helicopter provided by the police of the state of Goiás.[24]
Potassium alum dissolved in hydrochloric acid was used on clay, concrete, soil, and roofs. Caesium has a high affinity for many clays. Organic solvents, followed by potassium alum dissolved in hydrochloric acid, were used to treat waxed/greased floors and tables. Sodium hydroxide solutions, also followed by dissolved potassium alum, were used to treat synthetic floors, machines and typewriters.
Prussian blue was used to internally decontaminate many people, although by the time it was applied, much of the radioactive material had already migrated from the bloodstream to muscle tissue, greatly hampering its effectiveness. Urine from victims was treated with ion-exchange resin to compact the waste for ease of storage.
The cleanup operation was much harder for this event than it could have been because the source was opened and the active material was water-soluble. A sealed source need only be picked up, placed in a lead container, and transported to the radioactive waste storage. In the recovery of lost sources, the IAEA recommends careful planning and using a crane or other device to place shielding (such as a pallet of bricks or a concrete block) near the source to protect recovery workers.
The Goiânia accident spread significant radioactive contamination throughout the Aeroporto, Central, and Ferroviários districts. Even after the cleanup, 7 TBq of radioactivity remained unaccounted for.
Some of the key contamination sites:
Other contamination was also found in or on:[26]
The original teletherapy capsule was seized by the Brazilian military as soon as it was discovered, and since then the empty capsule has been on display at the Portuguese: Escola de Instrução Especializada ("School of Specialized Instruction") in Rio de Janeiro as a memento to those who participated in the cleanup of the contaminated area.
In 1991, a group of researchers collected blood samples from highly exposed survivors of the incident. Subsequent analysis resulted in the publication of numerous scientific articles.[27] [28] [29] [30]
A 1990 film, Portuguese: Césio 137 – O Pesadelo de Goiânia (Caesium-137 – The Nightmare of Goiânia), a dramatisation of the incident, was made by Roberto Pires.[31] It won several awards at the 1990 Festival de Brasília.[32] An episode of , "Thine Own Self," was partially inspired by the accident.[33]
Much of the radioactive substances were cleared after testing. However a gloom hung over the local residents, as they were asked for certificates stating that they were free of radioactivity. Also banned products from Goiânia created a public outcry, citing unjust discrimination.[34]
The state government of Goiás established the Portuguese: Fundação Leide das Neves Ferreira in February 1988, both to study the extent of contamination of the population as a result of the incident and to render aid to those affected.[35]