UNITED NATIONS, June 26: The radioactive materials needed to make a “dirty bomb” can be found in almost any country in the world, and more than 100 may have inadequate controls to prevent or even detect the theft of these materials, the United Nations International Atomic Energy Agency said on Tuesday.

The IAEA said while radioactive sources number in the millions, only a small percentage have enough strength to cause serious harm, and it called for priority focus on these materials.

“What is needed is cradle-to-grave control of powerful radioactive sources to protect them against terrorism or theft,” said IAEA chief Mohammed ElBaradei. “One of our priorities is to assist states in creating and strengthening national regulatory infrastructures to ensure that these radioactive sources are appropriately regulated and adequately secured at all times.”

Mr ElBaradei pointed out that while a number of countries that have regulatory systems in place are urgently stepping up security measures, many lack the resources or the national structures to effectively control radioactive sources. “Orphaned” radioactive sources — those that are outside official regulatory control — are widespread in the former Soviet Union.

The IAEA, working in collaboration with the United States Department of Energy and the Russian Federation’s Ministry for Atomic Energy, has established a tripartite working group to develop a coordinated and proactive strategy to locate, recover, secure and recycle orphan sources throughout the former Soviet Union, said a press note.

According to the Agency, a dirty bomb does not use radioactive material to produce a nuclear explosion, as a nuclear weapon would. Constructed using conventional explosives and radioactive material, the detonation of a dirty bomb would result in the dispersion of the radioactive material.

As with any explosion, people in the immediate vicinity could be killed or injured by the blast itself, while the dispersed radioactive material could cause radioactive exposure. In all likelihood, the most severe tangible impacts of a dirty bomb would be the social disruption associated with the evacuation, the subsequent clean-up of contaminated property and associated economic costs.