23 Apr (NucNet): The discovery of radioactive materials in scrap metal shops in India, and the acute exposure of a scrap dealer, has been classified as level 4 on the International Nuclear Events Scale (INES).
A summary of the incident, sent to the International Atomic Energy Agency (IAEA) yesterday, said India’s Atomic Energy Regulatory Board (AERB) received a report on 7 April 2010 from a hospital in New Delhi about a patient with suspected radiation-induced symptoms. Subsequent dose assessments indicated that the man had received an absorbed radiation energy dose of 3.7 Gray (Gy).
Two AERB officials were sent to the man’s shop, a scrap metal dealership in Mayapuri, New Delhi, where they confirmed the presence of radioactive material. Their survey also indicated the presence of radioactive material in two other shops in the neighbourhood.
As an immediate measure, shielding was provided to reduce radiation levels in affected areas. The sources were later found and secured as part of an emergency response by the Department of Atomic Energy and the Indian government. The area was declared safe from radiological contamination on 9 April.
Doses received by the experts and workers who performed the recovery operation were monitored and found to be within specified limits.
Further searches led to the recovery of an additional two radioactive Cobalt-60 (Co-60) sources at another scrap metal shop some 500 metres away. A further Co-60 source was recovered from the possession of a patient admitted to another hospital in New Delhi.
A total of 7 patients with radiation induced symptoms have reported to various hospitals to date. Their assessed doses through bio-dosimetry were in the range of 0.4 Gy to 3.7 Gy. For comparison: a dose of 5 Gy at one time usually leads to death within 14 days; the average dose from diagnostic X-ray is in the range of 0.1 to 20 milligray (mGy).
Investigations are now under way to identify where the Co-60 sources came from.
In March 2009, the AERB said it was working to stop incidents of low-level radioactive contamination in exported steel products after investigating “a few incidents” of low-level contamination in steel products exported to some European countries.
>>Related reports in the NucNet database (available to subscribers)
Further Steps Needed On Contaminated Material, Conference Hears (News No. 24, 25 February 2009)
Indian Regulators Pledge To Stop Low-Level Contamination In Steel Exports (News in Brief No. 26, 3 March 2009)
