Iodine-131 trips off false alarms in patient travel

Radiologists should not only take their patients' history but perhaps also record their future travel plans. Apparently, individuals undergoing diagnostic or therapeutic nuclear medicine procedures can trip radiation detectors designed to catch terrorists smuggling radioactive material.

One man set off an alarm in a tunnel while riding a bus from New York to Atlantic City, NJ, a few years ago. In the 1980s, two people undergoing radionuclide therapy set off detectors in the White House.

But the potential for these false alarms is rising as portable radiation monitors proliferate and the number of nuclear medicine scans increases, Dr. Lionel Zuckier said at the 2004 RSNA meeting.

Zuckier and colleagues at the University of Medicine and Dentistry of New Jersey found that iodine-131 can trigger alarms up to three months after its administration; gallium-67 and thallium-201 up to 30 days; indium-111 up to 17 days; and technetium-99m and iodine-123 up to three days.