When the Islamic State captured the city of Mosul in its 2014 blitzkrieg, the militant group obtained access to a highly lethal material that would have been useful for a “dirty weapon,” the Washington Post reports.
In taking Mosul, the Islamic State controlled a city filled to the brim with with guns, bombs, rockets and tanks, due in part to the number of military garrisons and bases located all over the city, but these were by no means the most deadly of the weapons to be found there.
Hidden away in medical devices stored on a college campus in Mosul were two quantities of cobalt-60, a synthetic radioactive isotope produced artificially in nuclear reactors. The isotope emits gamma rays at high intensity, making it effective in radiotherapy cancer treatments, however its high radioactivity also makes it perfect for a “dirty bomb,” or a weapon that uses conventional explosives to disperse radioactive materials across a targeted area, making it uninhabitable.
Indeed, even brief direct exposure to cobalt-60 without protective shielding is enough to kill a human being. The isotope, according to Slate science reporter Sam Kean, “fires off just enough radioactivity upfront to kill you (or at least cause serious cancers),” but retains enough radiation to make any area affected by fallout “inhospitable for future generations.”
In 1950, Manhattan Project scientist Leo Szilard calculated that a tenth of an ounce of cobalt-60 sprinkled on every square mile of planet Earth would be enough to wipe out the human race. Granted, this would still be quite a large quantity of the isotope, but it nevertheless illustrates its lethality.
In Washington, intelligence agencies were aware of the presence of the substance in Mosul and kept a close watch for any sign of its use, while nuclear and military experts theorized about the potency of the isotope and the potential damage it could do. Since cobalt degrades over time, its exact potency was not known to the experts.
Fears were peaked in late 2014 after an ISIS member announced the group had obtained radioactive material, in this case uranium, from Mosul University. While experts said the material was likely not potent enough to be cause for concern, Dina Esfandiary, a research associate with the Non-Proliferation and Disarmament Program at the International Institute for Strategic Studies, told Newsweek “Nothing is impossible. If they’re determined enough then they’ll find a way to develop a radiological weapon and use it.”
As they approached the location where cobalt-60 was last known to be stored, fighting neighborhood-to-neighborhood in Mosul’s densely populated districts, Iraqi commanders were brought into the fold and informed about the presence of the material.
Finally, after years of anxiety, earlier this year Iraqi government officials entered the storage room where the cobalt-using machines were housed.
What did they find?
The cobalt still sat inside the machines, untouched; the Islamic State never actually made use of the substance, though it sat under the group’s nose for years as it occupied Mosul.
“They are not that smart,” an Iraqi health ministry official said of the militant group.
While it isn’t clear why the group did not take advantage of and weaponize the material, U.S. officials and nuclear experts speculate the militants may not have had any practical way to remove the cobalt from the machines’ thick protective shielding without exposing themselves to lethal doses of radiation in the process.
American officials, however, said their concerns extend far beyond Mosul, as similar medical equipment containing radiological materials are used in many cities all over the world, some in conflict zones.
In several incidents earlier this year, ISIS demonstrated that it possessed some quantity of chemical weapons after victims of ISIS shelling and rocket strikes reported symptoms ranging from respiratory problems and vomiting, as well burns and blisters on the skin.
Mosul, now largely free of the yoke of the Islamic State, has been devastated by the group’s years-long occupation, as well as the U.S.-led coalition’s efforts to retake the city. While the battle for Mosul is finally over, rescue, aid and morgue workers are now burdened with the dark task of cleaning up the mountains of corpses that virtually cover the city’s urban landscape.
“A lot of blood has been shed,” said an employee at a morgue in Mosul. “Iraq used to have two rivers: the Tigris and the Euphrates. Now we have a third: the river of blood.”