Cobalt-60 is a common element in medical radiotherapy equipment used in cancer treatment. For about three years after ISIS overran the city, wary U.S. intelligence agencies were aware that two caches of potentially dangerous cobalt-60 were in storage on a Mosul college campus in machines that were estimated to be 30 years old.
Officials notified Iraqi military commanders about the threat, as their army battled ISIS block-by-block for control of the city for the past year or so.
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.
Fortunately, Iraqi forces recaptured Mosul and secured the cobalt-60 stockpile, which was still untouched in the storage room. Authorities still haven't figured out exactly why the ISIS fighters never sought to access the substance. One theory holds that it was too dangerous to extract the cobalt core from the machines without a risk of exposure to a lethal dose of radiation.
In this instance, Iraq, if not the entire world, seems to have lucked out. (Related: Read more about the the threat from weapons of this kind at Radiation.news.)
The difficulty is that machines containing cobalt-60 are in use all over the world by hospitals, clinics, universities and other institutions engaged in cancer treatment, medical research and the like, making the misuse of the substance a global threat.
"Similar equipment exists in hundreds of cities around the world, some of them in conflict zones."
Efforts are underway, however, to transition to new technologies that are less prone to terrorist exploitation. Whether cancer patients should submit themselves to radiation therapy, in any case, is another matter entirely.
Cobalt-60 loses some of its potency over time, but the Mosul machines could have easily delivered a kill shot of radiation at close range, the Post added.
Homeland security officials have long been concerned about the possibility of terrorists smuggling a dirty bomb into America and detonating it in a major American city, the Post noted.
Leaders of the Islamic State and al-Qaeda are known to have sought materials for a dirty bomb, a threat that has added urgency to efforts by U.S. agencies and private groups to improve security for machines with heavy concentrations of cobalt-60, or other radioactive elements...