R.A. had heard rumors that valuable equipment had been left in the disused clinic of the IGR (Location A). R.A. and a friend, W.P. went to the site of the disused clinic and tried to dismantle the teletherapy unit with simple tools. R.A. and W.P. finally succeeded in removing the rotating assembly. The shiny stainless steel casing appeared valuable to them and they took it in a wheelbarrow to R.A.’s house (Location B), half a kilometer from the clinic.
Since no contamination was found at the clinic, the source assembly was presumably still intact at this stage. However, from the moment they removed the rotating assembly, they would potentially have been exposed to the direct beam, as they would have been if they had rotated the source wheel into the ‘on’ position while it was still in the radiation head. This would have given a dose rate of 4.6 Gy-h~l at 1 m.
W.P. and R.A. were vomiting, but assumed that this was due to something they had eaten.
W.P. had diarrhea and felt dizzy, and one hand was swollen (oedema).
W.P. subsequently had a hand/wrist burn consistent with having held the rotating assembly with one hand/wrist over the beam aperture.
W.P. sought medical assistance. His symptoms were diagnosed as an allergic reaction caused by eating bad food. On medical advice he stayed at home for a week, feeling poorly and doing only light work.
The rotating assembly had been placed on the ground under a mango tree in R.A.’s garden. Here R.A. worked intermittently to remove the source wheel of the rotating shutter. In the course of the attempt he punctured the 1 mm thick window of the source capsule with a screwdriver and scooped out some of the source. Thinking it might be gunpowder, he attempted to light it. On 18 September he succeeded in removing the source wheel.
When measured on 2 October, the residual contamination under the mango tree gave a dose rate of 1.1 Gy-h~l at 1 m. The whole of R.A.’s house and its grounds were extensively contaminated. The house had to be demolished and the topsoil removed.
The pieces of the rotating assembly were sold to D.F., who lived next to the junkyard he managed (Junkyard I, Location C). The pieces were transported in a wheelbarrow (by an employee of D.F.). That night, D.F. went into the garage where the pieces had been placed and noticed a blue glow emanating from the source capsule. He thought it looked pretty and that the powder might be valuable (like a gemstone) or even supernatural, and took the capsule into the house. Over the next three days various neighbors, relatives and acquaintances were invited to see the capsule as a curiosity. During this time he and his wife M.F.1 examined the powder closely.
M.F.1 (dose 5.7 Gy) subsequently died. D.F. (dose 7.0 Gy) survived, possibly because he spent more time out of the house and his exposure was fractionated.
E.F.1, a friend of D.F.’s, visited him and with the aid of a screwdriver removed some fragments of the source from the capsule. These were about the size of rice grains but readily crumbled into powder. E.F.1 gave some of the colorful fragments to his brother E.F.2 and took the rest home. D.F. also distributed fragments to his family. Subsequently there were several instances of people dabbing the radioactive powder on their skin, as if it were the glitter used at carnival time.
M.F.1 was vomiting and had diarrhea. She was examined at Sao Lucas Hospital. The diagnosis was the same as for W.P. (an allergic reaction to something she had eaten) and she was sent home to rest. Her mother M.A.1 came over for two days to nurse her and then returned to her home, some distance from Goiânia, taking a significant amount of contamination with her.
M.A.1 had an estimated initial intake of 10 MBq (270 pd) and a dose of 4.3 Gy estimated on the basis of cytogenic analysis. Although critically ill at one stage, she survived.
The pieces of the rotating assembly were handled and worked on by D.F.’s employees, principally I.S. and A.S., to extract the lead. At one stage Z.S. visited and offered to return to cut up the pieces with an oxyacetylene torch. However, he forgot to do so.
I.S. and A.S. incurred doses of 4.5 Gy and 5.3 Gy respectively. Both subsequently died. Their exposures were probably acute while working on the effectively unshielded remnants of the source assembly.
W.P. was admitted to Santa Maria Hospital where he stayed until 27 Sept., when the skin effects of radiation exposure were diagnosed as a symptom of some disease, and he was transferred to the Tropical Diseases Hospital.
I.F., the brother of D.F., went to Junkyard I and was given some fragments of the source. He took them back to his house, next to a junkyard (Junkyard II, Location D). They were placed on the table during a meal. His six-year-old daughter L.F.2 handled them while eating (by hand), as did the rest of the family to a lesser extent.
L.F.2 subsequently died, having had an estimated intake of 1.0 GBq (27 md) and received an estimated dose of 6.0 Gy.
D.F. sold the lead and the remnants of the source assembly to the owner of Junkyard III (Location E).
K.S., an employee at Junkyard II, and another person, went back to the old IGR clinic and removed the remainder of the equipment, principally the shielding container (weighing about 300 kg), and took it to Junkyard II.
By this time a significant number of people were physically ill. M.F.1 was convinced that the glowing powder from the source assembly was causing the sickness. She went with G.S., an employee of D.F.’s, to Junkyard III and had him put the remnants of the rotating assembly and the source assembly in a bag. They took the bag by bus to the premises of the Vigilância Sanitária (Location F). G.S. carried the bag there from the bus on his shoulder. At these premises the bag was placed on the desk of Dr. P.M., and M.F.1 told him that it was “killing her family.”
G.S. incurred a significant radiation burn on his shoulder and an estimated whole body dose of 3.0 Gy, and had an estimated intake of 100 MBq (2.7 md).
Dr. P.M. left the source remnants in the bag on his desk for some time but was then worried enough to remove it to a courtyard and put it on a chair by the external wall of the premises. (It remained there for one day.)
Dr. P.M. received an estimated dose of 1.3 Gy. His intake was negligible (since the source remnants remained in the bag).
M.F.1 and G.S. were sent to a Health Centre, where the initial diagnosis was that they had contracted a tropical disease. They were then sent to the Tropical Diseases Hospital. Several other people who had been contaminated in the incident and showed similar symptoms had already been to the Tropical Diseases Hospital, and similar diagnoses had been made. However, one of the doctors, Dr. R.P., had begun to suspect that the patients’ skin lesions had been caused by radiation damage. Consequently, he contacted Dr. A.M., who worked both at the Tropical Diseases Hospital and as superintendent of the Toxicological Information Centre. Dr. A.M. had been contacted independently by Dr. P.M. from the Vigilância Sanitária about the suspicious package (the bag of source remnants), which he had originally thought contained pieces from x-ray equipment. After the patients had been further examined, Drs. R.P. and A.M. considered that the matter required further investigation. They contacted Dr. J.P. at the Department of the Environment of Goiás State. Dr. J.P. proposed that they have a medical physicist look at the suspicious package. Dr. J.P. knew a physicist, W.F., who happened to be visiting Goiânia at the time; however, he was unable to contact him until early the next day.
The pace of the events then quickened as the seriousness of the accident began to be appreciated; consequently, approximate times are given.
29 Sept. 8:00
W.F., the licensed medical physicist who was known to Dr. J.P. and who happened to be visiting Goiânia at the time, was reached by telephone and asked whether he would be able to take some measurements around a suspicious package at the Vigilância Sanitária. He thought he knew where he could borrow a dose rate monitor and agreed to do this. One of the government agencies concerned in the nuclear fuel cycle, NUCLEBRAS, has offices in Goiânia that deal with prospecting for uranium. W.F. went to these offices and asked to borrow a dose rate monitor. After some delay he was lent a scintillometer (a dose rate meter with a scintillation detector highly sensitive to radiation). It had a fast response time and a dynamic range of 0.02 to 30 /iGy-h~l, being normally used for geological measurements. He set off for the Vigilância Sanitária, and while still some distance away he switched on the monitor. It immediately deflected full scale irrespective of the direction in which he pointed it. He assumed the meter was defective and returned to the NUCLEBRAS offices to fetch a replacement.
W.F. arrived at the Vigilância Sanitária. Having switched on the replacement monitor upon leaving the NUCLEBRAS offices, he was by then convinced that there was a major source of radiation in the vicinity. In the interim Dr. P.M. had become worried enough to call the fire brigade. W.F. arrived just in time to dissuade the fire brigade from their initial intention of picking up the source and throwing it into a river.
W.F. then persuaded the occupants of the Vigilância Sanitária to vacate the premises. The police and fire brigade supervised to prevent anyone from re-entering the building.
Dr. P.M. explained where the source had come from and he and W.F. went together to Junkyard I. There they found that over a wide area the radiation monitor deflected off the scale, and there was evidence of contamination. This convinced them that the contamination was extensive. They talked to D.F. from Junkyard I and with some difficulty persuaded him, his family and many neighbors to vacate the area.
W.F. and others went to the offices of the Secretary for Health of Goiás State to inform the authorities of the incident and its significance and to obtain further assistance. As can perhaps be appreciated, the officials were incredulous of the account of the incident and the assessment of the potential scale of the evacuation necessary. The officials took some persuading that the matter was important enough to warrant the attention of the Secretary for Health. W.F. and others persevered and were eventually permitted to see him so they could apprise him of the seriousness of the situation.
The Director of the Department of Nuclear Installations in CNEN was reached by telephone as the nominated coordinator for nuclear emergencies (referred to as NEC). He suggested that they contact the hospital physicist at the IGR for help, since he would be better able to determine the nature of the incident and the extent of the area affected with the wider range of instruments at his disposal. NEC also contacted the licensed physicist and the physician from the IGR, and the source was tentatively identified as possibly originating from the IGR.
Several actions were taken more or less at the same time in Goiânia.
(a) The Tropical Diseases Hospital was contacted and informed that a number of people had been contaminated and were suffering from the effects of radiation exposure.
(b) The various elements of the civil defense forces (the police, the fire brigade, ambulances and hospitals) were alerted.
(c) The known sites of contamination, the Vigilância Sanitária and Junkyard I, were resurveyed with the equipment from the IGR.
(d) The Golds State Secretary for Health held a meeting and made plans for receiving contaminated persons in the city’s Olympic stadium (Location H). By this time the press was taking an interest in events.
Z.S. (who had earlier offered to cut up the pieces of the rotating assembly with an oxyacetylene torch) found W.F. and explained how the source assembly had been broken up and where the pieces had been taken. This enabled the monitoring team to identify more of the sites of major contamination and to evacuate more contaminated persons. On the night of 29-30 September, 22 people were identified at the stadium as potentially having been highly exposed. They were put into tents separate from the others. This segregation was based partly on contamination measurements and medical symptoms, but also on the family groupings at the sites of major contamination. Some initial screening was done by Dr. A.M. and a colleague, and those with lesions were sent to the Tropical Diseases Hospital to join other patients already there. By this time the hospital had been informed that the patients were contaminated and should be kept isolated.