Your phone could reveal your radiation exposure after a nuclear disaster

In the event of a nuclear attack or accident, personal electronics could be repurposed as radiation detectors.

A ceramic insulator found in many devices, such as cell phones and fitness trackers, gives off a glow under high heat that reveals its past nuclear radiation exposure, researchers report in the February Radiation Measurements. That insight may allow experts to gauge someone’s radiation dose in a matter of hours, whereas typical blood tests can take weeks.

“Everybody panics when it comes to radiation,” says study coauthor Robert Hayes, a nuclear engineer at North Carolina State University in Raleigh. Quickly estimating people’s risk of radiation-related sickness after a nuclear disaster could help triage emergency medical treatment.

When nuclear radiation floods the ceramic in electronic components called surface mount resistors, the radiation rearranges the distribution of electrons in defects in the ceramic’s crystalline structure. If heated to hundreds of degrees Celsius, the ceramic glows, and the wavelengths of light that make up that luminescence reveal the material’s electron distribution. From there, researchers can determine the dose of radiation that caused the material’s electron reshuffling.

Hayes and NC State colleague Ryan O’Mara tested their technique by blasting surface mount resistors with 0.005, 0.015, 0.03, 0.06, 0.125, 0.25 or 0.5 grays of radiation. (One gray represents one joule of radiation per kilogram of target material.) For the lower levels of radiation, the researchers could generally estimate doses within about 0.01 grays using the technique; at 0.5-gray exposure, the uncertainty was 0.05 grays.

This test is sensitive enough to judge whether someone likely needs immediate treatment for radiation poisoning, which may result from one to a few grays of radiation, Hayes says. It could also indicate whether someone has an increased risk of cancer — which could be induced by about 0.2 grays.

But the machine used to measure the ceramic’s luminescent glow costs about $150,000, so people in areas affected by nuclear disasters would have to send their personal electronics to specialized facilities for testing.