Goiânia accident - AbsoluteAstronomy.com

The Goiânia accident was a radioactive contamination

Radioactive contamination

Radioactive contamination, also called radiological contamination, is radioactive substances on surfaces, or within solids, liquids or gases , where their presence is unintended or undesirable, or the process giving rise to their presence in such places...

accident that occurred on September 13, 1987, at Goiânia

Goiânia

-Climate:The city has a tropical wet and dry climate with an average temperature of . There's a wet season, from October to April, and a dry one, from May to September. Annual rainfall is around 1,520 mm....

, in the Brazil

Brazil

Brazil , officially the Federative Republic of Brazil , is the largest country in South America. It is the world's fifth largest country, both by geographical area and by population with over 192 million people...

ian State of Goiás

Goiás

Goiás is a state of Brazil, located in the central part of the country. The name Goiás comes from the name of an indigenous community...

after an old radiotherapy source was taken from an abandoned hospital site in the city. It was subsequently handled by many people, resulting in four deaths and radioactive contamination of 245 other people, 20 of whom showed signs of radiation sickness and required treatment. Time
Time (magazine)
Time is an American news magazine. A European edition is published from London. Time Europe covers the Middle East, Africa and, since 2003, Latin America. An Asian edition is based in Hong Kong...

magazine has identified the accident as one of the world's "worst nuclear disasters".

Nature of the source

The source of the Goiânia accident was a small thimble

Thimble

A thimble is a small hard pitted cup worn for protection on the finger that pushes the needle in sewing.The earliest known thimble was Roman and was found at Pompeii. Made of bronze, its creation has been dated to the 1st century AD...

containing about 93 grams of highly radioactive

Radioactive decay

Radioactive decay is the process by which an atomic nucleus of an unstable atom loses energy by emitting ionizing particles . The emission is spontaneous, in that the atom decays without any physical interaction with another particle from outside the atom...

caesium chloride

Caesium chloride

Caesium chloride is the inorganic compound with the formula CsCl. This colorless solid is an important source of caesium ions in a variety of applications. Its crystal structure forms a major structural type where each caesium ion is coordinated by 8 chlorine ions...

(a caesium salt made with a radioisotope, caesium-137

Caesium-137

Caesium-137 is a radioactive isotope of caesium which is formed as a fission product by nuclear fission.It has a half-life of about 30.17 years, and decays by beta emission to a metastable nuclear isomer of barium-137: barium-137m . Caesium-137 is a radioactive isotope of caesium which is formed...

) encased in a shielding canister made of lead

Lead

Lead is a main-group element in the carbon group with the symbol Pb and atomic number 82. Lead is a soft, malleable poor metal. It is also counted as one of the heavy metals. Metallic lead has a bluish-white color after being freshly cut, but it soon tarnishes to a dull grayish color when exposed...

and steel

Steel

Steel is an alloy that consists mostly of iron and has a carbon content between 0.2% and 2.1% by weight, depending on the grade. Carbon is the most common alloying material for iron, but various other alloying elements are used, such as manganese, chromium, vanadium, and tungsten...

with an iridium

Iridium

Iridium is the chemical element with atomic number 77, and is represented by the symbol Ir. A very hard, brittle, silvery-white transition metal of the platinum family, iridium is the second-densest element and is the most corrosion-resistant metal, even at temperatures as high as 2000 °C...

window. 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.

Comparison of radioactivities
Goiânia source	TBq
1971	74
1987	50.9
Recovered	44
Unrecovered (c. 1987)	7
Unrecovered (c. 2008)	4.3
Smoke detector	0.000000037

The source emitted 74 terabecquerels

Becquerel

The becquerel is the SI-derived unit of radioactivity. One Bq is defined as the activity of a quantity of radioactive material in which one nucleus decays per second. The Bq unit is therefore equivalent to an inverse second, s−1...

(TBq) in 1971. The International Atomic Energy Agency

International Atomic Energy Agency

The International Atomic Energy Agency is an international organization that seeks to promote the peaceful use of nuclear energy, and to inhibit its use for any military purpose, including nuclear weapons. The IAEA was established as an autonomous organization on 29 July 1957...

(IAEA) describes the container—51 millimeters (2 inches) in diameter and 48 mm (1.8 inches) long—as an “international standard capsule.” The specific activity of the active solid was about 814 TBq

Becquerel

·kg⁻¹ of caesium 137

Caesium-137

(half life of 30 years). The dose rate at one meter from the source was 4.56 gray

Gray (unit)

The gray is the SI unit of absorbed radiation dose of ionizing radiation , and is defined as the absorption of one joule of ionizing radiation by one kilogram of matter ....

per hour (456 rad·hr⁻¹). While the serial number of the device was unknown, thus hindering definitive identification, the device was thought to be made in the United States at Oak Ridge National Laboratory

Oak Ridge National Laboratory

Oak Ridge National Laboratory is a multiprogram science and technology national laboratory managed for the United States Department of Energy by UT-Battelle. ORNL is the DOE's largest science and energy laboratory. ORNL is located in Oak Ridge, Tennessee, near Knoxville...

and was used as a radiation source for radiation therapy

Radiation therapy

Radiation therapy , radiation oncology, or radiotherapy , sometimes abbreviated to XRT or DXT, is the medical use of ionizing radiation, generally as part of cancer treatment to control malignant cells.Radiation therapy is commonly applied to the cancerous tumor because of its ability to control...

at the Goiânia hospital.

The IAEA document indicates that:

The dose rate due to external irradiation from uniform contamination of the ground by ¹³⁷Cs is
The internal dose for ingestion is
The internal dose for inhalation is

The IAEA states that the source contained 50.9 TBq (1375 Ci

Curie

The curie is a unit of radioactivity, defined asThis is roughly the activity of 1 gram of the radium isotope 226Ra, a substance studied by the pioneers of radiology, Marie and Pierre Curie, for whom the unit was named. In addition to the curie, activity can be measured using an SI derived unit,...

) when it was taken and that about 44 TBq (1200 Ci, 87%) of radioactivity has been recovered during the clean up operation. This means that 7 TBq remained in the environment; it will have decayed to about 4.3 TBq by 2008.

For comparison, the average modern smoke detector

Smoke detector

A smoke detector is a device that detects smoke, typically as an indicator of fire. Commercial, industrial, and mass residential devices issue a signal to a fire alarm system, while household detectors, known as smoke alarms, generally issue a local audible and/or visual alarm from the detector...

contains about 37 kBq (1 μCi) of ²⁴¹Am.

Hospital abandonment

The Instituto Goiano de Radioterapia (IGR), a private radiotherapy institute in Goiânia, was located just 1 km (0.621372736649807 mi) northwest of Praça Cívica, the administrative center of the city. It moved to its new premises in 1985, leaving behind a caesium-137 based teletherapy unit which had been purchased in 1977. The fate of the abandoned site was disputed in court between IGR and the Society of Saint Vincent de Paul

Society of Saint Vincent de Paul

The St Vincent de Paul Society is an international Roman Catholic voluntary organization dedicated to tackling poverty and disadvantage by providing direct practical assistance to anyone in need. Active in England & Wales since 1844, today it continues to address social and material need in all...

, then owner of the premises. On 11 September 1986, the Court of Goiás stated it had knowledge of the abandoned radiological material in the building.

Four months prior to the accident, on 4 May 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 objects that were left behind. Bezerril then warned president of Ipasgo, Lício Teixeira Borges, that he should take responsibility "for what would happen with the caesium bomb".

The court posted a security guard to protect the hazardous abandoned equipment. Meanwhile, the owners of IGR wrote several letters to the National Commission for Nuclear Energy, warning them about the danger of keeping a teletherapy unit at an abandoned site, but they could not remove the equipment by themselves once a court order prevented them from doing so.

Theft of the source

On 13 September 1987, the security guard in charge of daytime security, Voudireinão da Silva, did not show up to work, using a sick day to attend a cinema screening of Herbie Goes Bananas
Herbie Goes Bananas
Herbie Goes Bananas is the fourth of a series of films made by Walt Disney Productions starring Herbie – the white Volkswagen racing Beetle with a mind of its own. The film stars former Mel Brooks collaborators Cloris Leachman and Harvey Korman....

with his family. That same day, scavengers Roberto dos Santos Alves and Wagner Mota Pereira entered the partially demolished facility, found the teletherapy unit, which they thought might have some scrap value, placed it in a wheelbarrow, and took it to Alves' home, about 0.6 km north of the clinic. There, they partly dismantled the equipment, taking the billiard ball-sized caesium capsule out of the protective rotating head. The gamma radiation emitted by the capsule's iridium window nauseated the men, and within a day or so, the two men became ill, experiencing vomiting, diarrhea, and dizziness. The clinic's diagnosis was that the men were suffering an allergic reaction caused by eating bad food. The two continued their efforts to dismantle the unit, eventually rupturing the source capsule and exposing the radioactive material. The exposure eventually caused localized burns

Radiation burn

A radiation burn is damage to the skin or other biological tissue caused by exposure to radio frequency energy or ionizing radiation.The most common type of radiation burn is a sunburn caused by UV radiation. High exposure to X-rays during diagnostic medical imaging or radiotherapy can also result...

to their bodies, and one later had to have an arm amputated

Amputation

Amputation is the removal of a body extremity by trauma, prolonged constriction, or surgery. As a surgical measure, it is used to control pain or a disease process in the affected limb, such as malignancy or gangrene. In some cases, it is carried out on individuals as a preventative surgery for...

The source is partially broken

A few days later one man broke open the iridium window, which allowed him to see the caesium chloride emitting a deep blue light.

The exact mechanism by which the light was generated was not known at the time the IAEA report was written. The light is thought to be either fluorescence

Fluorescence

Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation of a different wavelength. It is a form of luminescence. In most cases, emitted light has a longer wavelength, and therefore lower energy, than the absorbed radiation...

or Cherenkov radiation

Cherenkov radiation

Cherenkov radiation is electromagnetic radiation emitted when a charged particle passes through a dielectric medium at a speed greater than the phase velocity of light in that medium...

associated with the absorption of moisture by the source; similar blue light was observed in 1988 at Oak Ridge National Laboratory

Oak Ridge National Laboratory

during the disencapsulation of a ¹³⁷Cs source. The man scooped out some of the radioactive caesium and tried to light it, thinking it was gunpowder

Gunpowder

Gunpowder, also known since in the late 19th century as black powder, was the first chemical explosive and the only one known until the mid 1800s. It is a mixture of sulfur, charcoal, and potassium nitrate - with the sulfur and charcoal acting as fuels, while the saltpeter works as an oxidizer...

, and eventually gave up.

The source is sold and dismantled

On September 18, Roberto dos Santos Alves and Wagner Mota Pereira sold the items to a nearby scrapyard

Wrecking yard

A scrapyard or junkyard is the location of a dismantling business where wrecked or decommissioned vehicles are brought, their usable parts are sold for use in operating vehicles, while the unusable metal parts, known as scrap metal parts, are sold to metal-recycling companies...

. That night the owner, Devair Alves Ferreira, went in the garage and saw the blue glow from the caesium capsule. Over the next three days, he invited friends and family to view the strange glowing substance. Ferreira intended to make a ring for his wife, Gabriela Maria Ferreira, out of the material.

Several people who visited the home came into contact with the dust and spread it around the local neighborhood and to other towns nearby. Ferreira's ownership led to many people becoming contaminated. A brother of the scrapyard owner used the dust to paint a blue cross on his abdomen. He also contaminated the animals at his farm, several of which died. At this scrapyard, a friend of Ferreira's (given as EF1 in the IAEA report) hammered open the lead casing. On 25 September 1987, Devair Alves Ferreira sold the scrap metal to another scrapyard. He survived the incident.

Ivo and his daughter

Ivo, Devair's brother, scraped dust out of the source, taking it to his house a short distance away. There he spread some of it on the floor. His 6-year-old daughter, Leide das Neves Ferreira, later ate while sitting on the floor, absorbing some of the radioactive material (1.0 GBq, total dose 6.0 Gy). She was also fascinated by the blue glow of the powder, applied it to her body and showed it off to her mother.

Gabriela Ferreira notifies authorities

Gabriela Maria Ferreira was the first to notice that many people around her had become severely sick all at the same time, and her actions from that point on probably saved lives. She first suspected the culprit was a beverage they had shared, but an analysis of the juice showed nothing untoward. On 28 September 1987 (15 days after the item was found), Gabriela went with one of her scrapyard employees to the scrapyard then in possession of the materials. She reclaimed them and transported them by bus in a plastic bag to a hospital. There, physician Paulo Roberto Monteiro rightly suspected that it was dangerous. He placed it in his garden on a chair to increase the distance between himself and the object. Because the remains of the source were kept in a plastic bag, the level of contamination at the hospital was low.

The source's radioactivity is detected

In the morning of 29 September 1987 a visiting medical physicist (named WF in the IAEA report) used a scintillation counter

Scintillation counter

A scintillation counter measures ionizing radiation. The sensor, called a scintillator, consists of a transparent crystal, usually phosphor, plastic , or organic liquid that fluoresces when struck by ionizing radiation. A sensitive photomultiplier tube measures the light from the crystal...

borrowed from NUCLEBRAS

NUCLEP

Nuclep is Nuclebrás Equipamentos Pesados SA, and Nuclebrás is Empresas Nucleares Brasileiras SA, part of Nuclep.Nuclep was founded in December 1975 to design and fabricate heavy components for nuclear power plants.-See also:...

(a national government agency which is involved in the nuclear fuel

Nuclear fuel

Nuclear fuel is a material that can be 'consumed' by fission or fusion to derive nuclear energy. Nuclear fuels are the most dense sources of energy available...

cycle, including searching for uranium ore) to confirm the presence of radioactivity. He spent most of the day on 29 September confirming the danger and persuading the authorities to take immediate action. The city, state, and national governments were all aware of the incident by the end of the day, and the accident response started that evening.

Health outcomes

About 130,000 people overwhelmed hospitals. Of those, 250 people, some with radioactive residue still on their skin, were found, through the use of Geiger counters, to be contaminated. Eventually, 20 people showed signs of radiation sickness and required treatment.

Ages in years are given, with dosages listed in Gy, or Gray

Gray (unit)

The gray is the SI unit of absorbed radiation dose of ionizing radiation , and is defined as the absorption of one joule of ionizing radiation by one kilogram of matter ....

Fatalities

Leide das Neves Ferreira, aged 6 (6.0 Gy, 600 REM), was the daughter of Ivo Ferreira. Initially, when an international team arrived to treat her, she was confined to an isolated room in the hospital because the hospital staff were afraid to go near her. She gradually developed swelling in the upper body, hair loss, kidney and lung damage, and internal bleeding. She died on October 23, 1987, of "septicemia and generalized infection" at the Marcilio Dias Navy Hospital, in Rio de Janeiro, as a result of the contamination. She was buried in a common cemetery in Goiania, in a special fiberglass coffin lined with lead to prevent the spread of radiation. There was a riot in the cemetery, where over 2,000 people armed with stones and bricks tried to prevent her burial.

Gabriela Maria Ferreira, aged 38 (5.7 Gy, 550 REM), wife of junkyard owner Devair Ferreira, became sick about three days after coming into contact with the substance. Her condition worsened, and she developed internal bleeding, especially in the limbs, eyes, and digestive tract, and suffered from hair loss. She died 23 October 1987, about a month after exposure.

Israel Baptista dos Santos, aged 22 (4.5 Gy, 450 REM), was an employee of Devair Ferreira who worked on the radioactive source primarily to extract the lead. He developed serious respiratory and lymphatic complications, was eventually admitted to hospital, and died 6 days later on 27 October 1987.

Admilson Alves de Souza, aged 18 (5.3 Gy, 500 REM), was also an employee of Devair Ferreira who worked on the radioactive source. He developed lung damage, internal bleeding, and heart damage, and died 18 October 1987.

Devair Ferreira himself survived despite receiving 7 Gy of radiation.

Other individuals

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

Dose fractionation

Experiments in radiation biology have found that as the absorbed dose of radiation increases, the number of cells which survive decreases. They have also found that if the radiation is fractionated into smaller doses, with one or more rest periods in between, fewer cells die. This is because of...

. Given time, the body's repair mechanisms will reverse cell damage caused by radiation. If the dose is spread over a long time period, these mechanisms can ameliorate the effects of radiation poisoning.

Other affected persons

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 persons had internal contamination. The majority of the internally contaminated persons only suffered small doses (< 50 mSv, less than a 1 in 400 risk of getting cancer as a result).

A thousand persons were identified as having suffered a dose which was greater than one year of background radiation

Background radiation

Background radiation is the ionizing radiation constantly present in the natural environment of the Earth, which is emitted by natural and artificial sources.-Overview:Both Natural and human-made background radiation varies by location....

; it is thought that 97% of these people had a dose of between 10 and 200 mSv (between 1 in 2 000 and 1 in 100 risk of developing cancer as a result).

Legal matters

In light of the deaths caused, the three doctors who had owned and run IGR were charged with criminal negligence

Criminal negligence

In the criminal law, criminal negligence is one of the three general classes of mens rea element required to constitute a conventional as opposed to strict liability offense. It is defined as an act that is:-Concept:...

. The main cause of this incident was the severe negligence of the facility's former operators who had left behind such a dangerous item. The accident demonstrated the importance of keeping an inventory and monitoring of all strong radiation sources by public authorities, which now is legally required in many countries. In 2000, CNEN, the National Nuclear Energy Commission, was ordered by the 8th Federal Court of Goiás to pay compensation of R$

Brazilian real

The real is the present-day currency of Brazil. Its sign is R$ and its ISO code is BRL. It is subdivided into 100 centavos ....

 1.3 million and to guarantee medical and psychological treatment for the direct and indirect victims of the accident and their descendants down to the third generation. Because 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. One of the medical doctors owning IGR and the clinic's physicist were ordered to pay R$ 100 000 for the derelict condition of the building. The two scrap metal dealers were not included as defendants in the public civil suit.

Objects and places

Topsoil

Topsoil is the upper, outermost layer of soil, usually the top to . It has the highest concentration of organic matter and microorganisms and is where most of the Earth's biological soil activity occurs.-Importance:...

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

Decontamination

Decontamination is the process of cleansing the human body to remove contamination by hazardous materials including chemicals, radioactive substances, and infectious material...

or disposed of as waste. In industry, the choice between decontaminating or disposing objects is based only on the economic value

Value (economics)

An economic value is the worth of a good or service as determined by the market.The economic value of a good or service has puzzled economists since the beginning of the discipline. First, economists tried to estimate the value of a good to an individual alone, and extend that definition to goods...

of the object and the ease of decontamination

Decontamination

Decontamination is the process of cleansing the human body to remove contamination by hazardous materials including chemicals, radioactive substances, and infectious material...

. However, in this case, the IAEA recognized that to reduce the psychological impact

Psychological trauma

Psychological trauma is a type of damage to the psyche that occurs as a result of a traumatic event...

of the event, greater effort should be 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 practiced.

Means and methods

After the houses were emptied, vacuum cleaners were used to remove dust before the surfaces, and plumbing was examined for radioactivity. Painted surfaces could be scraped, while floors were treated with acid and Prussian blue

Prussian blue

Prussian blue is a dark blue pigment with the idealized formula Fe718. Another name for the color Prussian blue is Berlin blue or, in painting, Parisian blue. Turnbull's blue is the same substance but is made from different reagents....

mixtures. Roofs were vacuumed and hosed, but two houses had to have their roofs removed. The waste from the clean up was moved out of the city to a remote place for storage.

Potassium alum

Potassium alum

Potassium alum, potash alum or tawas is the potassium double sulfate of aluminium. Its chemical formula is KAl2 and it is commonly found in its dodecahydrate form as KAl2·12. Alum is the common name for this chemical compound, given the nomenclature of potassium aluminum sulfate dodecahydrate...

dissolved in hydrochloric acid

Hydrochloric acid

Hydrochloric acid is a solution of hydrogen chloride in water, that is a highly corrosive, strong mineral acid with many industrial uses. It is found naturally in gastric acid....

was used on clay, cement, 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

Prussian blue

was used to internally decontaminate many humans. The urine was treated with ion exchange resin

Ion exchange resin

An ion-exchange resin or ion-exchange polymer is an insoluble matrix normally in the form of small beads, usually white or yellowish, fabricated from an organic polymer substrate. The material has highly developed structure of pores on the surface of which are sites with easily trapped and...

to compact the waste for ease of storage.

Recovery considerations

The cleanup operation was much harder for this event than it could have been because the source was opened, and the fact that the active material was water

Water

Water is a chemical substance with the chemical formula H2O. A water molecule contains one oxygen and two hydrogen atoms connected by covalent bonds. Water is a liquid at ambient conditions, but it often co-exists on Earth with its solid state, ice, and gaseous state . Water also exists in a...

soluble. A sealed source need only be picked up, placed in a lead

Lead

container and transported to the radioactive waste

Radioactive waste

Radioactive wastes are wastes that contain radioactive material. Radioactive wastes are usually by-products of nuclear power generation and other applications of nuclear fission or nuclear technology, such as research and medicine...

storage. In the recovery of lost sources, the IAEA recommends careful planning and using a crane

Crane (machine)

A crane is a type of machine, generally equipped with a hoist, wire ropes or chains, and sheaves, that can be used both to lift and lower materials and to move them horizontally. It uses one or more simple machines to create mechanical advantage and thus move loads beyond the normal capability of...

or other device to place shielding (such as pallet of brick

Brick

A brick is a block of ceramic material used in masonry construction, usually laid using various kinds of mortar. It has been regarded as one of the longest lasting and strongest building materials used throughout history.-History:...

s or a concrete

Concrete

Concrete is a composite construction material, composed of cement and other cementitious materials such as fly ash and slag cement, aggregate , water and chemical admixtures.The word concrete comes from the Latin word...

block) near the source to protect recovery workers.

Contamination locations

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:

Goiânia’s Instituto Goiano de Radioterapia (IGR) (16.6746°N 49.2641 °W) suffered no actual exposure or breach of radioactive contents, but the site is noteworthy as the source of deadly, unsecured material. The IGR clinic no longer exists, having been replaced around 2000 with the modernized Centro de Convenções convention center.
Roberto dos Santos' house (16.66848°N 49.26341 °W) on Rua 57. The radioactive source was here for about six days, and it was partially broken into.
Devair Ferreira's scrapyard (16.66713°N 49.26652 °W), on Rua 15A ("Junkyard I") in the Aeroporto section of the city, had possession of the items for 7 days. The caesium container was entirely dismantled, spreading significant contamination. Extreme radiation levels of up to 1.5 Sv h⁻¹ were found by investigators in the middle of the scrapyard.
Ivo Ferreira's house (16.66401°N 49.26911 °W) ("Junkyard II"), at 1F Rua 6. Some of the contamination was spread about the house, causing a fatality. The adjacent junkyard scavenged the remainder of parts from the IGR facility. The premises were contaminated with up to 2 Sv h⁻¹ of detectable radiation.
Junkyard III (16.66915°N 49.28003 °W). This junkyard had possession of the items for 3 days until they were sent away.
Vigilância Sanitária (16.675°N 49.273 °W). Here, the substance was quarantined, and an official cleanup response began.

Research

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.

External links

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