MIT indicates current exposure rules may be unreasonable

MIT has published a new study in Environmental Health Perspectives which analyzes the effect of high levels of constant radiation on the DNA of mice. The study found no measurable change after continuous exposure to levels of radiation 400 times greater than normal.
In the study, mice were exposed for five weeks. The result:

"these results demonstrate in an in vivo animal model that lowering the dose-rate suppresses the potentially deleterious impact of radiation, and calls attention to the need for a deeper understanding of the biological impact of low dose-rate radiation."

The same total dosage, when delivered "acutely" (all at once), did create the expected problems. In other words, radiation exposure appears not to be cumulative, or not nearly so much as has been thought.

This is an important finding. Current rules treat all radiation exposure as dangerous and seeks to minimize exposure, encouraging sometime ridiculous efforts to protect people from something that may not be dangerous.

The wide-spread evacuations following the Fukushima accident were largely protective. Because of earthquake damage, residents did not have the normal mobility, shelter, information, communication or health care systems available. As a result, thousands were evacuated out of an abundance of caution. This study, hopefully, will alleviate irrational fears and allow correct responses to future disasters.

"Current U.S. regulations require that residents of any area that reaches radiation levels eight times higher than background should be evacuated. However, the financial and emotional cost of such relocation may not be worthwhile, the researchers say." (Quote from MIT News.)

Anti-nuclear and environmentalist groups leverage (often irrational) fear of radiation to achieve their political ends. Hopefully, this study will reduce the potency of silly scare tactics and help government and industry to do the right thing.