| Accident scenario |
| At the construction site of the Gilan
combined-cycle fossil power plant (Iran), the welds on a boiler were examined
by industrial radiography during the night of 23-24 July. The source was
a 1.85x10(11) Bq (5 Ci) l92-Ir pellet, 2 mm in diameter, enclosed in a
stainless steel cylindrical capsule 7.5mm long with a 5.0mm diameter. At
some point that night, the source holder became detached from the radiography
device cable and fell into a concrete trench, unnoticed by the operator
K, an unskilled worker on the site, started work at 08.00 on 24July (day
1); shortly afterwards, he saw a metallic object in the trench and picked
it up. The exact circumstances of the irradiation are somewhat confused.
For an unknown but probably short period, the object was in the right pocket
of his trousers. He then moved it to the right chest pocket of his work
overalls, where it remained for the next 1.5h. He handled the capsule on
several occasions to inspect it. At around 09.30 he started to feel dizzy,
nauseated, and lethargic, and a burning sensation developed in his chest.
He apparently surmised that the object might be causing his symptoms; he
put it back into the trench and went to the workers' rest-room. At around
09.00 it was discovered that the source was missing from the radiography
device container. After a search, it was found in the trench at around
10.00 and stored in a shielded container. It was not until some hours later
that K told his colleagues that he had handled it. The site manager informed
the Atomic Energy Organization of Iran (ABOI) and sent the victim to the
nearest city for a blood test, which took place 8h after the exposure;
K was transported to Teheran on 27July (day 4) and placed in the AEOI medical
clinic. |
| Early clinical findings |
| Clinical examination revealed
erythema on the right side of his chest and upper abdomen. Blood was taken
for haematolofical and conventional cytogenetic assessments. He was transported
to an isolation room at the Imam Hossein Hospital in Teheran on 29July
(day 6). In the days that followed, the chest lesion continued to spread,
attaining an area of 30x15cm, and it progressed to moist desquamation.
By day 6, erythema had also developed over the medial side of his right
elbow and by day 10 in the palm of his left hand and on the anterior surface
of his right thigh. White blood cell and platelet counts fell progressively.
A bone marrow puncture on 12 August (day 20) confirmed aplasia. Despite
appropriate treatments through day 22 (antibiotics, platelet transfusion
and G-CSF infusion), improvement was limited. The Iranian physicians therefore
contacted the Curie Institute in France. The patient arrived in Paris on
day 24, was placed in an isolation room and treated by platelet transfusion,
antibiotics and morphine infusion. G-CSF treatment continued for 10 days
after his arrival. A bone marrow biopsy on day 35 was essentially normal.
Two months after hospitalization at the Curie Institute had begun, the
various skin lesions had not healed. It was therefore decided to perform
skin grafts for the chest and thigh lesions. The outcome of these operations
was excellent and the patient recovered completely by day 84. He returned
to Iran on day 94. |
| Chromosomal dosimetry |
| The two first blood samples (at days
5 and 10) were taken by the Iranian Cytogenetics laboratory. When the patient
was hospitalized at the Curie Institute, the IPSN (Institut de Protection
et Surete Nucleaire) Laboratory processed two additional blood samples
(days' 26 and 61). After the patient's transfer back to Iran, two final
blood samples were taken and processed by the Iranian laboratory at days
207 and 529. |
| References |
1. Voisin P, Assaei RG, Heidary A, Varzegar R, Zakeri F, Durand V, and
Sorokine-Durm I: Mathematical methods in biological dosimetry: the 1996
Iranian accident. Int. J. Radiat. Biol., 76: 1545-1554, 2000.
2. Cosset JM, Sharp C, Clough K, and Sheibani KM: A lost pigtail. J. Radiol.
Soc. Med., 92: 189-190, 1999. |
| Chromosome aberration analysis |