A powerful, disused radioactive source in Côte d'Ivoire has been secured with the assistance of IAEA experts and French and Côte d'Ivoire authorities. The sealed caesium-137 source had been left in a small bunker without proper security or safety measures in place, in the grounds of the University of Cocody in the country’s capital Abidjan.
The IAEA supported the safe removal and transport of the source to France, where it arrived on 30 October 2003, and will be conditioned and stored. France originally supplied the source to Côte d'Ivoire in 1969 for use in studies on food preservation and to reduce post-harvest food losses.
IAEA Africa Regional Projects Coordinator, Mr. Mokdad Maksoudi, said the caesium source had decayed to about 19,000 curies at the time of removal, yet remained highly dangerous. Caesium-137 - an artificially produced radioisotope with a half life of 30 years - is no longer used for most irradiator applications, although it can be recycled to produce small sources.
The source ranks in the highest category of radioactive sources, because of its potential to harm if uncontrolled. “It is a radioactive powder which, if it fell into the wrong hands, could be used to spike a dirty bomb. The small room it was stored in was abandoned and accessible to the public, and did not comply with any safety or security standards,” Mr Maksoudi said.
In addition to security concerns, the caesium source presented a health and safety hazard to a curious public, said Mr. Mohamed Al-Mughrabi, who headed the IAEA team that advised authorities on how to safely remove the source.
“It would have presented a serious problem if someone unsuspectingly decided to dismantle it…About 10-15 minutes exposure to an unshielded source of 19,000 curies would kill,” he said.
Several other radioactive sources also found at the site, including a 5 curie neutron source, were recovered and the bunker dismantled. As part of its role in overseeing the operation, the Agency assisted authorities with the regulatory requirements for shipping the caesium and other sources back to their country of origin and advised on how to safely remove and transport them. The operation was rolled out through a project under the African Regional Cooperative Agreement (AFRA: http://www.afra-iaea.org/), with France contributing $225,000 and the Agency $80,000.
Mr. Al-Mughrabi said worldwide a number of spent radioactive sources were unacceptably left where they had last been used. He estimated the extent of the problem to be, on average, between one to eight thousand curies per Member State.
Through its work, the Agency carries out regional technical cooperation projects that assist more than 80 countries to improve their national programmes for radiation and waste safety.
“The IAEA is working to reduce the threats posed to security, health and the environment by improperly stored sealed sources. To date it has performed over 50 conditioning operations of spent sealed sources worldwide, including 15 operations in Africa under the AFRA project,” Mr. Al-Mughrabi said.
To help national authorities manage other disused radioactive sources, future IAEA assistance missions are foreseen in the Democratic Republic of Congo, Haiti, Mozambique, Bolivia and El Salvador.