Researchers at Hiroshima University (HU) in Japan have developed a way to leverage the cameras on smartphones to provide accurate radiation readings. The system they created costs less than US$70 and could be a big help in disaster situations.
When a person is exposed to radiation, every second matters when it comes to getting treatment. The delivery of cytokines can stimulate the white blood cell production that is damaged by exposure; treatment with potassium iodide or Prussian blue can help eliminate radioactive particles from the body; and proper washing can prevent skin burns that might take days to show up.
In fact, those who receive a whole-body radiation dose equal to 4 grays, have a 50% chance of dying within 60 days if untreated. Grays (Gy) are units that express the amount of radiation a person has received, with one gray equal to one joule of radiation energy absorbed per kilogram of tissue.
That said, many current methods of measuring radiation exposure rely on complex lab analysis or expensive equipment. To help broaden the ability to test for exposure after catastrophic events, such as that which took place at Japan's Fukushima Daiichi nuclear plant in 2011, the HU researchers paired a radiochromic film known as EBT4 with a foldable portable scanner and a smartphone.
The film changes color instantly when exposed to radiation. And, while the change is visible to the naked eye, it's not really possible to ascertain exposure levels simply by looking at it. That's where the scanner and phone come in.
After the film has changed color, it can be placed in the scanner and an image can be captured by the smartphone's camera. By using mobile image-processing apps, the level of exposure can be calculated, all the way up to 10 Gy. This brings an affordable and accurate level of in-field radiation detection, saving significant time by not needing to get those affected to clinical settings for evaluation.
"To protect people in the event of a severe radiological or nuclear accident, voluntary on-site dose assessments and prompt decisions regarding medical actions must be performed immediately," says study corresponding author Hiroshi Yasuda, a professor at Hiroshima University’s Research Institute for Radiation Biology and Medicine. "Simplicity, universality, and cost-effectiveness are critical factors for these emergency measures."
The system was successfully tested using both Samsung and Apple smartphones. Now, Yasuda and his team are focused on standardizing protocols and ensuring the system performs reliably under a wide variety of environmental conditions. The paper describing the system has been published in the journal Radiation Measurements, and is open access so that others may benefit from the findings.
While the system works even better with desktop scanners, Yasuda says they wanted something more portable. "Our goal was to design a system that works even under the worst-case accident scenarios, such as after a natural disaster where infrastructure might be damaged," he concludes.
Source: Hiroshima University
