Prolonged Radiation Exposure: MIT Study Offers a New Look

Are nuclear accident radiation evacuation guidelines overly conservative?

That’s what a new study is suggesting. The study, from scientists at MIT and published in the journal Environmental Health Perspectives, suggests that in the event of a nuclear accident, most people are exposed to elevated, low dose-rate radiation. However, according to their research, low dose radiation, even at 400 times elevated rates, poses little risk to DNA.

Researchers could not identify any DNA damage in a study using lab mice subjected to radiation levels around 400 times higher than background levels (the ionizing radiation constantly present in the natural environment) for five weeks.

This study is significant because existing evacuation guidelines were based on research and analysis of acute radiation exposure rather than low level exposures. 

According to a news release from MIT’s News Office, Jacqueline Yanch, one of the authors of the study and a senior lecturer at MIT’s Department of Nuclear Science and Engineering, said, “This paper shows that you could go 400 times higher than average background levels and you’re still not detecting genetic damage. It could potentially have a big impact on tens if not hundreds of thousands of people in the vicinity of a nuclear powerplant accident or a nuclear bomb detonation, if we figure out just when we should evacuate and when it’s OK to stay where we are.” 

This study begins to shed light on the effects of lower doses of radiation over longer times, which have been less well-understood than the effects of high radiation doses.

Read more about the study here.