But an IAEA official has told RFE/RL that the Vienna-based nuclear watchdog is still awaiting an official reply from Kyrgyz officials -- a week after they announced that dangerous levels of the radioactive substance cesium-137 had been discovered aboard a freight train bound for Iran. The IAEA official added that Bishkek so far had not asked the agency for any assistance or support on the matter.
The seizure itself occurred days before its disclosure by the Kyrgyz government.
In late December, radiation detectors alerted Uzbek border guards to the presence of dangerous material. The guards then sent the train back to Kyrgyzstan, where the State Environmental Agency says it was first informed of the incident on December 29. Kyrgyz officials later seized the substance and stored it in a special holding area.
In an interview with RFE/RL's Kyrgyz Service on January 9, Almabek Aitikeev, a senior official with the Kyrgyz Emergency Situations Ministry, offered some details about the material. It was identified as cesium-137, a product of nuclear reactors and weapons testing that is often used in medical devices and gauges.
"Not quite a bucketload of radioactive waste material was there mixed in with sand, dust, and snow," Aitikeev said. "We did our work and sealed up the waste on December 31."
But details remain sketchy. The Kyrgyz National Security Service continues to decline requests for comment on the incident, as does the Kyrgyz state railway company Temir, which loaded the material in Kyrgyzstan along with nonferrous scrap metals onto the train, which belonged to a Tajik company. Kyrgyz officials confirm the train's ultimate destination was Iran, which is linked to the region via railway through Turkmenistan and regularly imports Central Asian scrap metal.Cesium In 'Very Dangerous' Form
Peter Zimmerman, a U.S. expert on nuclear proliferation and terrorism, says he finds the story disturbing on a number of levels. "There may be contamination elsewhere. We simply don't know because, first off, the Kyrgyz authorities have not been forthcoming," Zimmerman told RFE/RL. "And second, we don't have any other data, so we are speculating. If a [radioactive] source was broken, and the material, which looks like glow-in-the-dark table salt, could have been scattered well before it was found. And some amounts could be anywhere."
That raises serious public health concerns. But Zimmerman cautions that the lack of information makes it extremely difficult to speculate just how serious the risk could be.
What is clear is that cesium-137 is a dangerous radioactive isotope. Zimmerman, the former chief scientist at the U.S. Arms Control and Disarmament Agency, says that it would be the favored substance of terrorists seeking to build a radiological "dirty bomb" or to launch a so-called "I-cube attack," which would use the easy ingestion, inhalation, or immersion of the powdery chemical to kill on a large scale.
"Cesium chloride is very much like table salt," Zimmerman says. "It dissolves in water and it can be blown away, and so on. And this is a very dangerous form to use, simply because it can enter the environment easily and it can be spread easily by a terrorist."
Last August, in an op-ed in "The New York Times," Zimmerman and his colleagues warned of the dangers of cesium and other similar substances falling into terrorists' hands. "We believe that a first measure should be to get all cesium sources converted to something that uses a solid rather than a powder form. We think that's safer," he says.
As for the Kyrgyz case, Zimmerman believes that is unlikely to have involved any malice or smuggling, and that negligence or incompetence remain the chief culprits. Zimmerman added that one possibility is that a gauge containing the cesium-137 got caught up in the scrap metal in the shipment.
"In all probability, a radioactive source -- which was used for measuring the thickness of a steel band or something of that sort, or aluminum band -- was left behind when the equipment was scrapped, and that source got mixed in with the scrap metal in the shipment," he says. "This happens even in the most developed countries with the best radiation protection, once or twice a year."
Where the source may have come from is still a mystery.
Like many former Soviet states, Kyrgyzstan has areas of poorly secured radioactive material -- as does neighboring Tajikistan, the home country of the company that owns the train.Tajik Nuclear Leaks
Although the Tajik nuclear plant at Vostokredmet was shut down after the Soviet Union's collapse, the company that runs it still manages 10 dumps of radioactive materials around the northern Tajik city of Chkalovsk. Reports say that only one of these radioactive dump sites has been completely secured, one is still active, and the others are only partially closed.
In comments to RFE/RL's Tajik Service, Shavkat Bobojonov, the head of the Vostokredmet nuclear plant, denied any possibility of legal transfer of radioactive substances from the area. "There is no trace of cesium in the plant," he said. "Now, we don't sell any kind of scrap metals from what we have. We need it ourselves for our own work. Our radioactive scrap metals are collected separately and they remain here."
Two years ago, Tajikistan created a National Nuclear Agency in a bid to attract international investment to fully secure its radioactive materials. That move followed registered cases of nuclear smuggling out of the country.
"No [recent] cases of smuggled radioactive materials have been registered in Tajikistan," Muzaffar Yunusov, the deputy of the head of Vostokredmet, told RFE/RL's Tajik Service. "In the [Sughd] region and in the country, some cases of smuggled radioactive materials or 'illegal transfers' were registered, but that was two or three years ago."
Kubat Osmonbetov, a Kyrgyz geologist, raised the possibility last week that the Tajik train may have been used in the past to transport radioactive material from the Vostokredmet area -- and that the remains of that material had somehow been left in the wagon.
But for now, the experts can only speculate -- at least until Kyrgyz officials respond to the IAEA's request for more detailed information.
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