People rationally fear possible accidents spreading deadly radioactive materials. Indeed massive doses of radiation did kill 38 emergency workers at Chernobyl, and the fallout of short-lived iodine resulted in 4000 cases of thyroid cancer and 15 deaths. However there is no evidence of the thousands of hypothetical deaths predicted by extrapolation of deadly exposures to lower radiation doses. Opponents of nuclear power have now hyped this death number up to one million, without observable evidence.
Using simplistic mathematical extrapolations from the effects of high-radiation accidents, nuclear power opponents claim that no amount of radiation is safe — not even the low-level natural radiation that comes from the sky and from earth’s radioactive potassium, uranium, and thorium created billions of years ago. Potassium is in our food and our bodies. Rocks contains the thorium and uranium that decays to radon or fuels electric power plants.
Reporting about the Fukushima accident created hysteria without basis. A UN scientific committee charged with investigating the accident’s health effects reported in December that no radiation health effects have been observed among public or workers, and it cautioned against extrapolation to predict health effects of low-level radiation. Radiation superstition causes great harm. Japan is wasting billions of dollars preventing repopulation of radiologically safe areas. Hundreds have died from evacuation stress. Importing liquified natural gas to replace nuclear power has driven Japan’s balance of trade negative.
People unnecessarily fear low-level radiation from accident-dispersed material, buried waste, or medical procedures. EPA required Yucca Mountain engineers to limit accidental releases to just 1/20th of natural radiation for 10,000 years. Dental X-ray technicians routinely drape lead blankets on patients to protect them, but it would take over 10,000 such X-rays to observe any health effect.
Prolonged radiation exposure is safe at natural environmental levels; each cell rapidly repairs DNA strand breaks: one per second per cell. Early life evolved when the natural radiation rate was 3 times greater than now. Today people living in places where natural radiation is 5 times normal exhibit no more cancers. People living in mile-high Denver get more cosmic radiation, but exhibit no more cancers.
Radiation dose rates are as important as doses. High radiation rates overwhelm natural cellular defenses. Doses deadly to Chernobyl workers would have no effect if spread over a lifetime. Cancers are destroyed by multiple concentrated radiation treatments, allowing time between for less-irradiated tissue to recover. In 2012 MIT radiation researchers discovered no DNA damage from exposure rates 30 times as great as natural radiation, and Lawrence Berkeley Lab scientists actually observed how low-level radiation stimulated repair within cells. Long-term, low-dose radiation is benign.
Nuclear industry and shipyard workers exposed to low-level radiation developed fewer cancers. Accidental contamination of building steel by recycling a medical radiation source exposed 8000 Taiwan residents to radiation 7 times natural levels over 30 years, and cancer rates were dramatically reduced. Last year the Dose Response Journal and the American Nuclear Society published compendia of articles evidencing how low-level radiation is benign or healthful.
The vague radiation regulation, “as low as reasonably achievable” encourages ever more costly impediments to affordable nuclear power. This could be fixed with “as high as reasonably safe” limits that are set with evidence, as practiced for other environmental hazards. Nuclear power can solve our energy, climate, and poverty crises. Should we forsake the future of the planet by clinging to a superstition?"
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