Nuclear safety

Terrorism and Radiation: Understanding the Real Threat To Our Cities

The importance of understanding the real levels of radiation risk.


The Boston Marathon attack has drawn new attention to the risk of radiation poisoning from a dirty bomb detonated in a heavily-populated urban area. Bostonians were inconvenienced by the shutting down of their city for a day; imagine if it had been a dirty bomb and a quarter million people had been ordered to evacuate their homes and offices, because of false fears about the amount of radiation which is actually dangerous.

A recent New York Times report, "U.S. Rethinks How to Respond to Nuclear Disaster," offers a helpful reminder that the greatest threat from terrorism is often what Washington does in response, such as launching unnecessary foreign wars or clamping down on civil liberties. Every crisis can become an excuse for Congress to loot the American treasury, impose new taxes, and grow the power and intrusiveness of government. Nuclear radiation, fanned by media-generated panic and ignorance, is always at the top of the list of most feared events and is therefore an area particularly open to government overreaction.  

After the 2011 Fukushima nuclear accident, Japan, following conventional guidelines, evacuated 160,000 persons from their homes, based on exposure levels of 2 REM (a REM is the unit of measure used to gauge radiation damage to human tissue). Yet not a single person died and hardly any got ill, even among the emergency nuclear workers at the reactor.

Actual radiation sickness begins at exposure of 100 REM, some 50 times the risk used to evacuate Japanese civilians. However even this risk can be minimized by staying indoors and closing windows. Later the Japanese government raised the limit for responders to 250 millisieverts (25 REM) from the initial 100 millisieverts (10 REM) which was inhibiting emergency response.

This excessive caution all comes from old U.S. limits of 15 millirem (.015 REM) which was considered the threat level of radiation for humans. For perspective consider that the average American is exposed to 360 millirems (.360 REM) per year while pilots and residents of high cities, such as Denver, get .920 REM. A Scientific American article explained how Japanese authorities ordered evacuation of anybody living within 20 kilometers of the stricken plant and told those within 30 kilometers to take shelter and stay indoors. It also reported that the U.S. Nuclear Regulatory Commission then recommended that any American within 80 kilometers evacuate the area. That's the kind of panic response we might expect here in America if we get hit with a dirty bomb.

My 2005 article "Radiation Limits, Dirty Bombs and Chaos" described much about nuclear radiation dangers, how to protect oneself, and about the wrong advice given by government agencies. Even today, Washington shies away from declaring what amount of radiation is dangerous. FEMA (Federal Emergency Management Administration) removed its initial post-9/11 instructions to just run away from any radiation. That was the old ALARA (As Little Radiation As Possible) FEMA rule. However, even today I can't find any specifics on the FEMA website about what level of radiation starts to be dangerous. Also, one can spend hours on the Homeland Security website looking in vain for similar information.

Recent hearings by the House Homeland Security Subcommittee focused on the possibility of the Boston bombing attack having been a radiological one. Yet those hearings featured no discussion of different radiation danger thresholds, while New York's Police Commissioner for Counter Terrorism described the threat as if they still used the 15 millirem limit. He said that the consequence of a dirty bomb the size of the devices used in Boston would contaminate a large part of the city, devastating its economic life with major evacuations of population.  

In March the EPA posted new, much higher potential guidelines for commentary and environmentalists promptly attacked them. But in fact those environmentalists may simply fear that a realistic radiation threat analysis could start unwinding much of their general activism against the use of nuclear power. While the EPA website now shows that health risks begin at 50 REM, it still uses the old, lower numbers for its threat warnings. For example, EPA still uses the 15 millirem limits for other issues, such as for residents in the vicinity of the Yucca Mountain waste storage site in Nevada. Also EPA still uses the 15 millirem limits for superfund cleanups, thus adding hundreds of millions, if not billions, of dollars to the costs of such work. 50 REM is 3,500 times 15 millirem (.015) and even 50 is lower than the 100 REM threshold commonly used for radiation sickness. That would be 7,000 times as high.

Initially, the old EPA limit may have been supposed to help ward off the threat of cancer. But these limits came into effect after World War 2 when scientists knew little about radiation's threat to human beings. Today, however, there is a vast body of evidence showing that low doses of radiation, up to 10 REM, build resistance to many diseases and prolong human life. After Hiroshima, victims not killed actually lived longer than average life spans.

The EPA's long reliance on these levels weakens America's civil defense. Many EPA critics believe it is due to the agency not wanting to provoke criticism by extreme environmentalists, who appear to oppose almost any measures that would lessen public worry about "nukes." Many environmentalists do indeed stoke fears in order to prevent the establishment of new nuclear electric energy plants and to promote universal nuclear disarmament. In response to the EPA's March announcement, for instance, one leading environmentalist website immediately attacked the agency and came out against any modification to the government's radiation rules. So far, this fear-mongering seems to be paying off. As The New York Times story cited above notes, Washington has so far failed to adjust its radiation danger thresholds.

The exaggerated threats from the Environmental Protection Agency guidelines are further exacerbated by the pervasive theory of Linear No-Threshold Dose Hypothesis (LNT), which extrapolates statistics to infinite, and frequently idiotic, extremes. For example, LNT deducts that, if falling 100 feet onto concrete is invariably fatal, then out of 10,000 people falling one inch, 10 of them will die from the fall. Or if 100 aspirin is a fatal does, then out of 100 people each taking one aspirin, one of them will die. By such reasoning any tiny amount of radiation will kill some number of people out of every million exposed. LNT is how the government came up with many of its dubious risk guidelines for chemicals and minerals—all while scientific research has progressed to the point where we can actually measure parts per billion, thus creating fear that almost any product may be dangerous.   

Forbes magazine recently explained how LNT does not take the immune system into account:

The linear no-threshold dose hypothesis (LNT) does not apply to doses less than 10 rem, (note Japan's evacuation above 2 Rem, Ed) which is the region encompassing background levels around the world, and is the region of most importance to nuclear energy, most medical procedures and most areas affected by accidents………– radiation doses less than about 10 rem (0.1 Sv) are no big deal.  LNT does not apply to doses less than 10 rem    

To recap, LNT is a supposition that all radiation is deadly and there is no dose below which harmful effects will not occur. Double the dose, double the cancers. First put forward after WWII by Hermann Muller, and adopted by the world body, including UNSCEAR, its primary use was as a Cold War bargaining chip to force cessation of nuclear weapons testing.  The fear of radiation that took over the worldview was a side-effect…. Although rarely discussed, LNT does not take into account the organisms immune system, biological recovery time between doses or other relevant mechanisms that operate at low doses on an actual organism versus cells in a petri dish.

Forbes' detailed article further explains: "UNSCEAR also found no observable health effects from last year's nuclear accident in Fukushima.  No effects.  The Japanese people can start eating their own food again, and moving back into areas only lightly contaminated with radiation levels that are similar to background in many areas of the world like Colorado and Brazil."

The threat of terrorism now makes it vital for American civil authorities to properly understand the real risks involved. Imagine the problems that would arise from police and firemen running away from a dirty bomb attack based on false information about exposure to low doses of radiation. A city could be put in chaos.

I first learned about this reality from attending meetings of Doctors for Disaster Preparedness, run by the wise Dr. Jane Orient. She explained how after 9/11 she found that the Tuscon, Arizona fire department had been given radiation detectors showing 15 millirem as the threat level. She herself then provided them with more realistic detectors.

Thankfully, there is (slow) international progress in better understanding radiation risks. For example, the United Nations Scientific Committee on the Effects of Atomic Radiation has finally admitted that we can't use the LNT hypothesis to predict cancer from low doses of radiation.

An excellent little book titled Under-Exposed describes radiation effects (and even the medical benefits of low doses) in great detail. For converting different measurements in the confusing world of radiation herewith is a very useful chart calculator. Another link shows specific health effects from different radiation levels.    

The threat of homegrown terrorism is not going away. Washington must prevent future panics, unnecessary evacuations, and accompanying economic catastrophes by explaining to the American people the real levels of radiation risk.

NEXT: Fight Among States for SpaceX's Business

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  1. Recent hearings by the House Homeland Security Subcommittee focused on the possibility of the Boston bombing attack having been a radiological one.

    Have the feds even considered that cities might be attacked with bombs that spread trans fats everywhere? Fast food restaurants? Food trucks? Jumbo sodas? Plastic bags? Bottled water? There is real damage that free society can do to a city, and local authorities have already proven they can put dangers into perspective.

    1. What about someone flying a cruise missile into the San Andreas fault? You ever think of that, smart guy?

      1. We all have our little faults, Epi. Mine’s in California.

        1. There’s a strong streak of good in you, Hugh. But then nobody’s perfect…almost nobody.

          1. My mother lives in Hackensack.

            1. Some people can read War and Peace and come away thinking it’s a simple adventure story. Others can read the ingredients on a chewing gum wrapper and unlock the secrets of the universe.

              1. Do you know why the number two hundred is so vitally descriptive to both you and me, Hugh? It’s your weight and my I.Q.

      2. I’m scared, please find a half naked model to hold me.

    2. up to I looked at the bank draft that said $5552, I be certain that my mom in-law truley making money parttime at there labtop.. there brothers friend has been doing this 4 only about 17 months and just now paid for the morgage on there mini mansion and got a great Volkswagen Golf GTI. read more at
      (Go to site and open “Home” for details)

  2. relax. you’re soaking in it.

  3. uptil I saw the bank draft which said $7814, I did not believe …that…my neighbours mother woz like really erning money in there spare time on their computer.. there aunts neighbour started doing this for only about six months and resantly took care of the mortgage on their villa and purchased a top of the range Subaru Impreza. I went here…. http://WWW.DAZ7.COM

  4. So, let me get this straight. The metric(s) that the govt. is using to assess risk from radiation attacks are inaccurate/biased towards greater harm than is actually present?


    Color me not shocked.

    1. But .08 being impairment is rock-solid science when it’s coming from the same source.


  5. I’m more worried about “broken arrows” than terrorists getting some nuke dust.

    Since 1950, there have been 32 nuclear weapon accidents, known as “Broken Arrows.” A Broken Arrow is defined as an unexpected event involving nuclear weapons that result in the accidental launching, firing, detonating, theft or loss of the weapon. To date, six nuclear weapons have been lost and never recovered.…..atic.shtml

  6. As Jon Basil Utley explains, the best way to prevent unnecessary future panics is by understanding the real levels of radiation risk.

    Understand real levels of radiation risk? WHY DO YOU HATE THE CHILDREN!?

  7. That was the old ALARA (As Little Radiation As Possible) FEMA rule.

    “As Low As Reasonably Achievable”

    True story.

    1. The gov’ment needs to shift to more of an AHARS philosophy: As Much As Reasonably Safe

      Using ALARA is wasteful and does not save lives.

  8. A little OT but this was from the A.M. links regarding spent nuclear fuel storage:

    Stormy Dragon| 5.7.13 @ 12:48PM |#

    They are subsidized in that they have no way of safely disposing of their waste products and depend on billions of dollars of tax payer funding to manage that.

    I wanted to respond to this: Nuclear “waste” is not waste. It has the vast majority of usable energy still stored in the rods. We just don’t have the reactors built yet to use it. We have the technology already though. And, nuclear waste storage is not funded by the taxpayers. A portion of every cent/kWh you pay for nuclear electricity is for spent fuel storage. Who do you think was funding Yucca mountain before Obama and Reid shut it down?


  9. Continued…

    But really, who pays for fossil fuel waste disposal? Fine particulate that is also radioactive is spewed into the atmosphere for all to breath in from fossil combustion – for free. That which does not go up through the stack, as in a coal plants case, is dumped in ash ponds beside the plant. Who pays for that? That toxic metal pond is never going to disappear. Nuclear waste is so tiny in amount compared to the waste from fossil fuel burning as to almost be a joke that it is such an issue. The entire waste produced by the nuclear industry in France (75% of France’s electricity) over the last 30 years fits in a warehouse.

    This is what nuclear waste is: solid ceramic fuel rods, completely encased in zircaloy, and then store in essentially indestructible casks.

    Not a single person in the history of nuclear power has been killed or injured from radioactive waste from nuclear power. Can you say that about coal combustion particulate?

    1. I always found the whole idea of nuclear waste a bit odd. As you said, there’s still lots of energy stored in there. Otherwise, if the nuclear fuel were truly spent, these rods would be as radioactive as bricks.

      Maybe “waste” is the right term ironically, to denote wasting energy. If the technology to recycle or further make use of the rods matures, could we dig out the ones we’ve disposed of?

      1. Definitely. Yucca’s design philosophy was to allow for retrieval of the fuel rods in the future – which was smart. Nevada is completely dumb for letting that this thing be stopped. It would have been a cash cow for the state for a long time and eventually could make Nevada the Saudi Arabia of nuclear energy.

        Right now U-235 is so plentiful and cheap to mine from the ground we don’t really need to reprocess spent fuel, but in the future we will use the energy in these rods.

        1. I think there is alot of misinformation regarding nuclear energy and its potential. I myself had bought into some of that misinformation. Nuclear needs to be unleashed.

  10. Science and reason don’t really matter when it comes to radiation. It’s so spooky to most people that their emotions are all that matter. All that a terrorist would need to do is add a few old radium watch dials or smoke detectors to a bomb and call it a “dirty bomb.” When authorities announced that it only contaminated a single block, and only added .0001% to the average background radiation, all most people would hear was “radiation” and never go within a mile of the site.

    XKCD did a very good radiation dose infographic.

    1. It’s incredible the fear radiation puts into people.

      It doesn’t help that every regulatory body uses linear no-threshold to measure cancer risk from radiation dose. There is no good evidence that below a 1 Sv/year dose that cancer rates are any higher than someone only receiving a background radiation dose. In fact, more evidence is pointing towards hormesis effects reducing cancer occurrence when exposed to low doses of radiation.

      But no, people are still forced to live in shelters and not return to their homes in Fukushima to avoid a radiation dose equal to that of the natural background radiation from living in Denver, Colorado.

      FUD – Fear, Uncertainty, and Doubt.

      1. Yes, radiation hormesis is an important concept. “The dose makes the poison,” as Paracelsus said, and it applies here as well.

  11. g back often can fend hermes belt off the attacker and usually does not lead to greater injury.”

  12. ALARA = As Low As Reasonably Acheivable
    Commercial nuclear power routinely performs cost/benefit analysis on shielding vs. dose picked up by workers, always considering that employees must stop work in radiation controlled areas when they reach their annual dose limit. In the US, the limit is 5 REM for radiation workers.…..alara.html

  13. Sounds like a solid plan to me dude.

  14. merican civil authorities to properly understand the real risks involved. Imagine th

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