THANK YOU WALL STREET JOURNAL!
Denver has particularly high natural radioactivity. It
comes primarily from radioactive radon gas, emitted from tiny concentrations of
uranium found in local granite. If you live there, you get, on average, an
extra dose of .3 rem of radiation per year (on top of the .62 rem that the
average American absorbs annually from various sources). A rem is the unit of measure
used to gauge radiation damage to human tissue.
The International Commission on Radiological Protection
recommends evacuation of a locality whenever the excess radiation dose exceeds
.1 rem per year. But that's one-third of what I call the "Denver dose."
Applied strictly, the ICRP standard would seem to require the immediate
evacuation of Denver.
* INTERESTING, HUH? I DID NOT KNOW THIS ABOUT DENVER!
[D]espite its high radiation levels, Denver generally has
a lower cancer rate than the rest of the United States. Some scientists
interpret this as evidence that low levels of radiation induce cancer
resistance; I think it is more likely that lifestyle differences account for
the disparity.
* YEP. I WAS THINKING THE SAME THING!
Now consider the most famous victim of the March 2011
tsunami in Japan: the Fukushima Daiichi nuclear power plant.
Two workers at the reactor were killed... by the tsunami...
which is believed to have been 50 feet high at the site.
* BY THE TSUNAMI ITSELF - NOT BY RADIATION POISONING.
But over the following weeks and months, the fear grew
that the ultimate victims of this damaged nuke would number in the thousands or
tens of thousands. The "hot spots" in Japan that frightened many
people showed radiation at the level of .1 rem, a number quite small compared
with the average excess dose that people happily live with in Denver.
* WOW...! YA SEE WHAT I MEAN ABOUT NEEDING TO READ! I HAD
NO FRIGGIN' IDEA! PUTS THINGS IN PERSPECTIVE... CONTEXT IS EVERYTHING!
If you are exposed to a dose of 100 rem or more, you will
get sick right away from radiation illness. You know what that's like from
people who have had radiation therapy: nausea, loss of hair, a general feeling
of weakness. In the Fukushima accident, nobody got a dose this big; workers
were restricted in their hours of exposure to try to make sure that none
received a dose greater than 25 rem (although some exceeded this level).
At a larger dose — 250 to 350 rem — the symptoms become
life-threatening. Essential enzymes are damaged, and your chance of dying (if
untreated) is 50%.
* GOOD TO KNOW! AGAIN... CONTEXT!
Nevertheless, even a small number of rem can trigger an
eventual cancer. A dose of 25 rem causes no radiation illness, but it gives you
a 1% chance of getting cancer—in addition to the 20% chance you already have
from "natural" causes. For larger doses, the danger is proportional
to the dose, so a 50-rem dose gives you a 2% chance of getting cancer; 75 rem
ups that to 3%. The cancer effects of these doses, from 25 to 75 rem, are well
established by studies of the excess cancers caused by the atomic bombs at
Hiroshima and Nagasaki in 1945. (A recent study of butterflies near Fukushima
confirms the well-known fact that radiation leads to mutations in insects and
other simple life-forms. Research on those exposed to the atomic bombs shows,
however, no similar mutations in higher species such as humans.)
* FOLKS... I'M FINDING THIS FASCINATING!
* FROM THIS POINT ON THE ARTICLE GETS A BIT MORE...
umm... CHALLENGING TO FOLLOW... SO I'M GONNA SKIP MOST OF THE "MATH"
AND LEAVE IT TO THOSE WHO ARE ALSO FASCINATED BY THIS ARTICLE TO READ IT IN
FULL BY FOLLOWING THE LINK PROVIDED UP ABOVE. IN THE MEANTIME... LET ME GET TO
THE CONCLUSION:
The most thoughtful high-number estimate of deaths that
will be caused by the Fukushima disaster comes from Richard Garwin, a renowned
nuclear expert. He has written that the best estimate for the number of deaths
is about 1,500 — well above my estimate but still only 10% of the immediate
tsunami deaths.
* THE AUTHOR OF THIS PIECE IS DR. RICHARD MULLER,
PROFESSOR OF PHYSICS AT UC BERKLEY. THIS ESSAY IS ADAPTED FROM HIS NEW BOOK,
"ENERGY FOR FUTURE PRESIDENTS: THE SCIENCE BEHIND THE HEADLINES."
I am uncomfortable with these large numbers of predicted
deaths. They are based on a theory that assumes proportionality in the way that
radiation increases the likelihood of cancer — a theory that has never been
tested, will not be tested in the foreseeable future, and which is known to
fail for leukemia.
I can't be sure that the theory is wrong, but I consider
these relatively large numbers for Denver and Fukushima to be misleading.
Remember that Denver has a lower cancer rate than the rest of the U.S., not a
higher one. There is a strong argument for ignoring radiation dangers below the
level of the Denver dose. In doing so, we would be ignoring risks that are
unobservable and which we routinely ignore (and properly so) in other
circumstances.
The tsunami that hit Japan in March 2011 was horrendous.
Over 15,000 people were killed by the giant wave itself. The economic
consequences of the reactor destruction were massive. The human consequences,
in terms of death and evacuation, were also large. But the radiation deaths
will likely be a number so small, compared with the tsunami deaths, that they should
not be a central consideration in policy decisions.
The reactor at Fukushima wasn't designed to withstand a
9.0 earthquake or a 50-foot tsunami. Surrounding land was contaminated, and it
will take years to recover. But it is remarkable how small the nuclear damage
is compared with that of the earthquake and tsunami. The backup systems of the
nuclear reactors in Japan (and in the U.S.) should be bolstered to make sure
this never happens again. We should always learn from tragedy. But should the
Fukushima accident be used as a reason for putting an end to nuclear power?
* ABSOLUTELY NOT!
Looking back more than a year after the event, it is
clear that the Fukushima reactor complex, though nowhere close to state-of-the-art,
was adequately designed to contain radiation. New reactors can be made even
safer, of course, but the bottom line is that Fukushima passed the test.
The great tragedy of the Fukushima accident is that Japan
shut down all its nuclear reactors. Even though officials have now turned two
back on, the hardships and economic disruptions induced by this policy will be
enormous and will dwarf any danger from the reactors themselves.
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