Activists have often claimed that the United States Nuclear Regulatory Committee is in the pocket of the nuclear industry.   However, based on the attitude of some of the recent commissioners, that seems to be quite the opposite of the truth, as is especially evident with former chairman Gregory Jaczko.

Jaczko was first appointed as a commissioner in 2005 and was promoted to the head commissioner and chairman of the agency in 2009.   He served until his resignation last year.  Jaczko was controversial for the entirety of his time at the NRC, and especially after becoming chairman.  He was widely accused of withholding information, in an attempt to slow or stop regulatory approval.  For example, in 2011, Jaczko failed to release sufficient information to allow the Yucca Mountain project to be evaluated properly, effectively halting approval from moving forward.   Jaczko was also accused by NRC staffers of frequently losing his temper and verbally assaulting those working under him.

It has always been clear that Jaczko’s opinion of nuclear energy has been generally unfavorable.  Indeed, he was the only commissioner to vote against approval of new plant licenses in the United States in 2012.   He was also generally not well received by the nuclear industry.

Yet the extent of Gregory Jaczko’s anti-nuclear feelings did not become entirely apparent until after his resignation from the NRC, in July 2012.   As a commissioner, Jaczko was not able to provide entirely candid comments on nuclear energy.  Had he spoken out directly against nuclear energy, it would have shown a very obvious conflict of interest with his regulatory position.  Yet, after resigning, Jaczko stated that he believed that ALL US nuclear reactors are so flawed and unsafe that they should be shut down as soon as possible. When asked why he did not state this during his time on the commission, Jaczko stated ” didn’t really come to it until recently.”

Calling for what amounts to a complete phase-out of nuclear energy puts Jaczko on a very extreme end of the spectrum.   It is very disturbing, though not entirely surprising, to learn that NRC had been chaired for three years by someone who is so anti-nuclear that he wants a full nuclear phase-out.   It’s the equivalent of someone who believes that humans are not fit for flight being the head of the Federal Aviation Administration.   Indeed, with such extreme views, they may as well have just made Helen Caldicott or Amory Lovins the NRC chair.

Unfortunately, if you thought we were done with this guy, that is not the case.

In addition to the distinct possibility that his mindset is not entirely uncommon at the NRC, it seems Jaczko has found his way back into a federal position.   He was just appointed to oversee the National Nuclear Security Administration.

Via the Hill:

Reid appoints former NRC chief Jaczko to nuclear panel

Former Nuclear Regulatory Commission (NRC) Chairman Gregory Jaczko was appointed Thursday to a new panel charged with monitoring the agency that oversees the nation’s nuclear weapons stockpile.

Senate Majority Leader Harry Reid (D-Nev.) tapped Jaczko — a former aide for the Nevada Democrat — for the position with the Congressional Advisory Panel on the Governance of the Nuclear Security Enterprise.

The panel was created by the 2013 National Defense Authorization Act. Its purpose is to make recommendations for improving operations at the Energy Department’s (DOE) nuclear weapons agency.

Those suggestions regarding the DOE’s National Nuclear Security Administration (NNSA) will be revealed in a report that’s due by February, 2014.

Jaczko has kept a low profile following an unceremonious departure from the NRC in which he resigned his post following allegations that he verbally abused staff.

His appointment to the 12-member panel, as well as a book deal he signed with Simon and Schuster on Wednesday about “Jaczko’s controversial years as the top nuclear regulator in the country,” will change that.

The controversial former NRC chairman’s appointment to the panel will likely rile conservatives.

Well, it has certainly riled me!

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What can I say.  I am mad.   I am ripping mad.  I’m disgusted.  I’ve seen a level of dishonesty and scientific misinformation so grotesque, I don’t even know what to say.

One expects that vested interests will tweak data or publish biased studies to support their own causes from time to time.  It’s dishonest and unacceptable, but it happens.  Still, sometimes the level of dishonesty is so severe it really shocks the conscious.

Such is the case with a recent “study” from the Radiation and Public Health Project.   It is so dishonest in its claims it really makes me wonder about the pathology of those who are behind it.  What is their goal?  To they, deep down, think they are serving a greater good with these lies?   Have they justified this to themselves through some rationalization that preserves their need for attention and to appear to be heros?   I’m sure a psychologist could have a field day.

Here is how it was reported in Yahoo News:

Fukushima fallout may be causing illness in American babies: Study
A new study from the Radiation and Public Health Project found that babies born in the western United States as well as other Pacific countries shortly after the Fukushima nuclear disaster in Japan in March 2011 may be at greater risk for congenital hypothyroidism.

Babies born in places including Hawaii, Alaska, California, Oregon and Washington shortly after Fukushima were 28 percent more likely to suffer from the illness, according to the study, than children born in those same regions one year earlier. The illness, if untreated, can cause permanent handicaps in both the body and brain.

According to the U.S. National Library of Medicine, “If untreated, congenital hypothyroidism can lead to intellectual disability and abnormal growth. In the United States and many other countries, all newborns are tested for congenital hypothyroidism. If treatment begins in the first month after birth, infants usually develop normally.”

But… how could this possibly be?

It is true that nuclear fission produces a significant quantity of iodine-131, a radioactive isotope which can cause damage to the thyroid, due to its high biological uptake and tendency to accumulate in the thyroid.   Thyroid tissue is radiation-sensitive to begin with, so in nuclear accidents, iodine-131 is one of the greatest concerns.

Of course, we are talking about the United States of America.  This is thousands of miles from Japan and any iodine-131 that might make it across the Pacific would be expected to be extremely dilute.   Not only that, but with a half-life of only eight days, the fact that it takes a minimum of a few days for atmospheric material to traverse the Pacific (and usually more than that) means that a good portion of the isotope would have decayed by the time it reached the US.

This is born out by the fact that when iodine-131 (which normally does not occur in nature) was detected in the US, after the Fukushima incident, the levels were miniscule.  Radioisotopes like iodine-131 can be detected at extremely low levels. This is done by collecting samples of precipitation, dust or air and placing them in a detector which can detect the characteristic energy levels of the gamma ray photons radioisotopes emit.  When a gamma ray of the energy associated with iodine-131 is detected, it indicates an atom of the isotope has decayed.  Since its half-life is so short, even a few hundred atoms of iodine-131 will produce detectable radiation, if they are present in a sample.

It is a testament to the precision of modern gamma spectrometers that iodine-131 could be detected at all in both the US and Europe.  Yet, although it was detected, in some cases, the levels were so low that the actual concentration could not even be reliably established.    This is not a big surprise, given that even in Tokyo, which was thousands of miles closer to Fukushima, the levels of iodine-131 only briefly exceeded what is considered the “safe” standard for infants.   It should be noted that the standard is extremely conservative.

If that is not compelling reason enough to be skeptical of claims that the iodine-131 levels in the US were high enough to cause harm to infants, it should also be noted that an entire generation of US citizens was exposed to hundreds or thousands of times more iodine-131 from atmospheric nuclear testing.   What harm this may have caused is still a matter of debate.  it likely did result in some additional cases of thyroid cancer, but it certainly did not lead to a large number of kids of the 1950’s and 1960’s with major thyroid problems.

So how could these babies possibly have been damaged by Fukishima fallout?

IT DIDN’T

Lets take a look at the actual study, which can be downloaded here.

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Recently stories have been making the rounds about how Japan is coping with the aftermath of the tsunami and the partial meltdown that occurred two years ago.  It is as sad as it is predictable that the fears of radiation would become the most lingering and harmful effect.   Even as the radiation itself has faded to background levels for most of the effected areas, public anxiety remains high.   This is exactly what happened with Chernobyl and other incidents.

Via the Associated Press:

Stress Emerges As Major Health Issue In Fukushima
MINAMI-SOMA, Japan (AP) — Japan’s radiation nightmare has turned the lively home that truck driver Takahiro Ishitani once shared with his wife and three sons into a cluttered bachelor pad.

A coffee mug full of cigarette butts, a towel and other odds and ends sit on a low table in the apartment’s small living room. He offers a visitor a takeout box lunch, his main source of sustenance these days. Laundry hangs inside so it won’t absorb the radiation that remains in the ground, two years after an earthquake and tsunami caused meltdowns and explosions at the Fukushima Dai-ichi nuclear power plant, about 30 kilometers (18 miles) to the south.

To escape this lonely weekday existence, the 42-year-old Ishitani drives three hours up winding roads every weekend to see his family, which has moved away because of fears that radiation could harm the children.

“If it really is safe, I want them to come back,” says Ishitani, a stocky man with a small beard on the tip of his chin. “But it’s hard to know. Different people say different things, and that adds to my stress. I don’t know whom to trust.”

Just as with Three Mile Island and Chernobyl, mental distress could be one of the biggest health issues to emerge from this disaster, experts say. While attention has focused on the potential cancer risks, they remain unclear. What is clear is that the uncertainty and the upheaval it’s caused in people’s lives is already exacting a very real and pervasive psychological toll.

“It’s one of the biggest problems,” said Seiji Yasumura, a professor of public health at Fukushima Medical University.

Ishitani collapsed on the street with an ulcer nine months into the disaster. He was hospitalized for three days and still takes stomach medicine. The slightest tremor wakes him at night, and then he can’t back to sleep as he worries about the future.

Will his youngest son, 8-year-old Ryusei, ever be able to play in the woods and catch crawfish in the river as Ishitani did as a child? How long can his family continue this divided life? Will his now half-deserted hometown of Minami-Soma even survive — or shrivel and die?

They can and should move back now. The tiny increase in radiation is trivial compared to the amount of damage this has done to the social fabric of the areas effected. Sadly, very few seem to be advocating this while many continue to cash in on the tragedy as a way of promoting their own agenda, often through fear-mongering. More efforts to inform the public are definitely necessary. Sadly, they seem to be lacking

I have been asked on a number of occasions whether there will ever be a nuclear powered car. The idea of powering a car by nuclear fission certainly seems to have some obvious appeal. The energy density of the fuel for a nuclear reactor is so great that it would be possible to build a car that never needed to be refueled, having a reactor core capable of long outlasting the useful lifespan of the car itself. The average life expectancy of a car is about 11 years and many accumulate 200,000 miles or more. However, a nuclear reactor could, in principle, power a car for decades. Thus, only those who kept their car well past the point of it being a classic would ever need to be concerned about running low on fuel.

Despite the appeal of never needing to buy fuel or worry about mileage, there are a number of reasons why a small nuclear reactor just does not work well as the power plant for a road vehicle.  In principle, a nuclear reactor could be made small enough, but doing so push the inherent limitations of fission and result in an exceptionally expensive and problematic vehicle.

Of course, in a sense, all vehicles are really nuclear powered.  Fossil fuels contain energy that is derived from ancient plant material, thus being an indirect way of using solar energy, which, of course, was produced by a nuclear reaction.   Electric cars also use nuclear energy, whether or not they are connected to a nuclear-powered grid, since all energy on earth had to come from a nuclear reaction at some point.

Powering vehicles with nuclear fission is thus entirely possible if the fission reactors are used to provide grid electricity for charging electric car batteries or if the energy from the reactors produces synthetic fuel or even hydrogen.   This is a much more economical and realistic means of having the energy for transportation generated by nuclear power than having everyone drive around with a reactor under their hood.

Of course there are other types of nuclear energy aside from fission.  Unfortunately, none would actually be likely to work for an automobile.

Nuclear Fission:

Nuclear reactors are a really great way of producing energy for static applications and for ships and submarines.  However, for automobiles, they turn out to be a lot more trouble than they are worth.  In 1958, Ford did create an illustration of what a nuclear-powered car would look like, dubbing it the Nucleon, but the Nucleon was more of a publicity piece than a viable transportation concept.  No land vehicle propelled by a nuclear reactor has ever been built. The Soviet Union designed several small, transportable nuclear power plants, and the US Army even built a prototype of a road-transportable reactor, but these were not propelled by the nuclear reactors.

For one thing, the regulatory hurdles to getting a nuclear reactor into an automobile are likely to be insurmountable.  All nuclear power reactors must conform to strict safety and security guidelines.  In the case of an automobile, it is probably not a bad thing that safety regulations would prevent it from taking to the road.  The core of an operating nuclear reactor does indeed become very radioactive, and if a road accident lead to a containment breach, the decay of short-lived isotopes could produce lethal levels of radiation exposure to the cars occupants.

Because of the radiation produced by an operating reactors core, all reactors that operate near people must also have substantial shielding.  For static applications, this really is not a problem.  Just having a large amount of water around the reactor provides ample shielding from both gamma rays and neutrons.  Concrete also works well, and in circumstances where a lesser volume is desired, dense metal like lead can be used.  This is also no problem for ships and submarines, which need ballast anyway.  However, to build a truly portable reactor, as much be in a car, the amount of shielding required presents a real problem.  At a minimum, the reactor core would need to be surrounded by a combination of heavy materials to block gamma rays and some kind of neutron shield, which might be composed of large amounts of water or an organic material like polyethylene.

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For decades, a nuclear fuel fabrication facility has operated on the outskirts of Toronto, Ontario.  Here, in a small industrial area, natural uranium oxide is brought to be compressed into small pellets, which are used for fuel in Canadian nuclear reactors.  The uranium is not enriched, as Canadian nuclear reactors use natural uranium with .7% uranium-235.   The material is identical to what is found in rocks and soil around the world, although it is purified and concentrated.  It’s about as common in the crust of the earth as tin, and, on rare occasions, may be found in a nearly pure oxide form in nature, as the result of geological forces.

No nuclear activities actually go on at the facility and the material does not result in any more radiation than would be found in many rock quarries.  The material is not a radiation hazard and only slightly toxic, considerably less toxic than substances like cadmium or mercury.

The plant also has never been a secret.  Granted, there are no big signs displaying the fact that the product produced on site happens to be uranium, but its operated completely in the open.  Copies of relevant licenses and permits can be obtained from the Canadian government.  Workers at the plant are free to discuss the nature of their employment openly.  If you knocked on the door of the plant and asked whoever came to open it what happens there, they would surely tell you that they make uranium fuel pellets.   There’s absolutely nothing hidden about it.

However, it seems that most in the community were simply unaware that the plant existed or that in this normal looking building uranium was being made into pellets.  They just went about their every day lives presuming that thenondescript building must be doing some non-scary industrial process, like storing large amounts of chlorine gas or hydrofluoric acid.

Until one day someone found out the horrible truth, that had never even been hidden to begin with…
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The answer, it turns out is “probably” or “we’re pretty sure they do.” or “Almost for sure, most of them should.”

That’s right.  We’re not entirely sure, and as time goes on we’re becoming less sure.   That’s because we don’t test them and haven’t done so for two decades.

How it was and how we got here:

A nuclear weapon is a very complex piece of engineering and physics.  There are many parts that have to work properly for the weapon to actually detonate.   The core must implode in a manner that results in the correct final geometry.  It must undergo fission before it is blown apart, sometimes requiring additional neutrons be provided by a pulsed neutron generator or by boosting with a small amount of fusion.  In hydrogen bombs, energy from the primary must be channeled into the secondary and produce fusion.   The time tolerances involved are less than nanoseconds.

For this reason, nuclear weapon designs were initially always tested at full scale, in prototype devices that would then become production weapons.  The first tests were conducted in the atmosphere.  Hundreds of such tests, some of multiple megatons were conducted by the United States and Soviet Union in the 1940’s, 1950’s and 1960’s.   These tests had multiple purposes.  In addition to validating the viability of the weapons designs, they were used to better understand the physics involved, with data collected to help guide future weapons design.  Tests were also used to determine the effects of weapons on structures, aiding in the design of nuclear-resistant structures, communications systems and weapons platforms.

In 1963 the United States and Soviet Union signed the Partial Test Ban Treaty.  The treaty ended the testing of nuclear devices in the atmosphere, underwater or outer space by the signing parties.  After 1963, all US and Soviet tests would take place underground, in shafts designed to completely contain the explosions and prevent any fallout from entering the atmosphere.    For the most part, this was successful, although there were occasional minor leaks and at least one major breach of containment due to an unmapped fissure in 1970.  France and China continued to conduct atmospheric testing, having not been party to the 1963 treaty.  The last atmospheric nuclear test was conducted by China in 1980.  Since that time, all tests have been underground.

By the late 1960’s, the superpowers had generally ended the practice of testing nuclear weapons at their full yield.   Having acquired a much better understanding of the physics and engineering behind nuclear weapons, it was no longer considered necessary to test the secondary stages of nuclear weapons at their full yield.   Testing the fission primaries, with either no secondary component, or a greatly reduced secondary yield provided ample data on the reliability of the weapon design.

The only exception to this was the rare circumstance where a new type of weapon was developed, with a vastly different design than previous weapons.  The 1971 Cannikin test was one example of a high yield weapon tested underground. At five megatons, the exceptional yield of the test device required extreme measures be taken to contain the blast. The test was conducted at the bottom of a 1.8 kilometer deep shaft, drilled through solid rock on a remote island off the coast of Alaska. The weapon tested was the W71, a highly unique warhead designed for the Spartan anti-ballistic missile system. The new warhead was designed to produce an extremely high x-ray and neutron flux and to operate in the extreme environment of outer space, possibly being subjected to radiation from other nuclear explosions. Given these special design criteria, it was determined that a full scale test of the system was necessary.

In 1974, the US and Soviet Union signed the Threshold Test Ban Treaty, limiting nuclear tests to a maximum of 150 kilotons. By the time the treaty was signed, it was no longer necessary to test weapons at their full design yield, so the treaty was largely symbolic. Since larger tests require more complex and extensive containment measures, and because they were no longer necessary, both countries had generally abandoned large tests by that time. Although other nuclear powers were not party to the treaty, by the 1970’s, full yield weapons testing was no longer necessary for established nuclear powers.

The United States and Soviet Union continued to conduct nuclear tests, mostly with yields of a few kilotons, throughout the 1980’s. France, China and the UK also conducted nuclear tests through the 1980s and into the early 1990’s.

The End of Nuclear Tests (for established nuclear powers):

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In a nuclear reactor, a fissile substance, such as uranium or plutonium produces a fission chain reaction.   In such substances, a few atoms fission from time to time, due to spontaneous fission or neutrons introduced from an outside source.  When this happens, more neutrons are released.   Each fission reaction releases more neutrons.  Some of those neutrons strike other atoms and produce fission and some do not.   In a small pile of uranium, a few fissions will happen, from time to time, and those fissions will sometimes cause more fissions to occur, but most neutrons will not produce more fission, so while one fission event may spawn a few more, it will not produce anything sustained.

You might expect that as the amount of fissile material increases, the amount of fissions would increase at a relatively linear rate to the amount of material.  That, however, is not what happens.   As more material is added, very little happens.  Spontaneous fissions continue to occur, but the rate at which secondary fissions occur increases by a very modest amount.  Then, at some point, it all changes, the relatively flat increase in fission rate suddenly surges, and within microseconds, the material has gone form a few isolated fission events to continuous sustained fission.

The reactor has reached what is known as “critical mass.”  This is the point where each fission that occurs produces at least one more fission on average.  It may go beyond being critical to becoming “super critical” where the rate of fission increases dramatically in a short period of time.  Because critical mass is such a sudden tipping point, it can come without warning, as has been the case in criticality accidents.  It’s also why a nuclear bomb can go from almost no fissions at all to fissioning nearly the entire mass of plutonium or uranium in nanoseconds.

What does this have to do with disease?  More than one might think.

If an infected individual is introduced to a population of uninfected individuals, whether the disease will be able to grow to a full-blown outbreak has a great deal to do with what percent of the population is susceptible to that disease, for example, because they are not vaccinated.   The exact number of persons without vaccination needed to sustain an outbreak depends on the nature of the disease, such as how easily it is passed on, how long it lasts and the method of transmission.

In general, if only a small number of persons are susceptible to the disease, the initial infected person may pass it onto one or more others and those others may or may not pass it on to one or more others, but the number of cases stemming from each infected individual is small enough that the disease never gets a real foothold in the population and never manages to infect more than a handful of persons before the outbreak fizzles out.

At some point, however, enough people are not vaccinated that each new infection has a pretty good chance of passing it onto someone else, thus sustaining the outbreak and resulting in numbers of infections that increase exponentially.

And that is how THIS happens:

The above graph is from the CDC and shows the number of cases of Pertussis (whooping cough) in Washington State, although similar graphs exist showing outbreaks elsewhere.  Pertussis is a disease that causes fits of coughing and respiratory distress.  In adults, it can be a miserable condition, but is rarely dangerous.  In children, it may require hospitalization, and in infants, it can easily be deadly.

The reason for the outbreak boils down to the fact that more and more parents have been avoiding vaccinating their children because of bogus claims of vaccine dangers.   This trend has been going since the 1990’s.  Health officials had been warning of the dangers, but most saw few repercussions.  Whooping cough rates have been going up, but only at a relatively slow rate.

Then, between 2011 and 2012, the number of cases increased by as much as 25-50 times!   This graph gives a bit more context to how dramatic this spike is.

At this point, that threshold has been crossed.  There is no longer enough herd immunity to prevent an outbreak.  Critical mass has been reached.  The outbreak is now self-sustaining and can grow and spread across the population.   A single case no longer just triggers a handful more.   Once one of these outbreaks starts, it’s very difficult to stop, at least until the level of vaccination has reached the point where the virus no longer can spread from host to host fast enough to sustain the epidemic.

Understanding the mathematics behind this is more than academic.  It explains how a massive outbreak can creep up on the population.   As the level of immunization drops, there may not be a dramatic increase in cases until it suddenly spikes.

This time from the Bulletin of Atomic Scientists, a number of anti-nuclear activists are up in arms about the SILEX process.  It’s a type of laser-based isotope enrichment which is currently ready to move from the laboratory to industrial-scale pilot plants.

Here are some major points from the article “SILEX and Proliferation” by Scott Kemp, along with my responses.

SILEX is a new enrichment technology that happens to be well suited for making nuclear weapons. The benefits of commercializing SILEX are not yet established, but the proliferation risks are significant.

It is not any more “well suited” to nuclear weapons production than to commercial fuel production nor is the benefit of the process not established.   Any method of enrichment can be used to produce highly enriched or low enrichment uranium.  It is simply an issue of how many cycles of enrichment the material is subjected to.   This is true of gaseous diffusion, gas centrifuge enrichment and all other types.  As such, any facility that can produce low levels of enrichment for power reactors can also produce highly enriched uranium, although at lower quantities.   SILEX is not unique in its ability to be adapted to any level of enrichment.

The advantage of commercialization is simply that it has the potential to be more efficient when it comes to producing enriched uranium.  Enrichment is a necessarily energy intensive process involving high facilities.  Laser-based methods are the next step in reducing enrichment costs.   Right now, additional enrichment capacity is badly needed.  Much of the enriched uranium sold for commercial fuel comes from the down blending of highly enriched uranium from Russian nuclear weapons.  However, that stockpile is not going to last forever.   The Megatons to Megawatts program, a partnership between the United States and Russia is due to end in 2013, potentially increasing the global need for uranium enrichment dramatically.

The long term solution may be to switch to fuel cycles that do not require uranium enrichment, but for the time being, it is a vital part of the fuel cycle.

Dozens of countries are poised to copy SILEX if a US project demonstrates that the technology can be built on a commercial scale. The technical barriers, to the extent they exist, are not likely to endure the test of time.

This is a silly argument that has been made many times before.  The US is not the only game in town and whether or not the US decides to pursue this technology or shoot itself in the foot by not doing so will not change anything.  We went through this same thing with gas centrifuge technology.  The US failed to fully commercialize gas centrifuges out of similar fears and today we are left using the antiquated method of gaseous diffusion while all other countries switched to the more effective centrifuge method years ago.

The Nuclear Regulatory Commission has refused to consider the proliferation risk in its decision to issue a license for the first commercial SILEX facility, despite a statutory obligation to do so. Only a few weeks remain for Congress to intervene.

Lasers exist. The technology exists to tune them to the frequencies of uranium isotopes. The theory behind the system is well known. The US is not the only game in town. Whether the US peruses this technology has no bearing on proliferation outside the US. We can only control whether we choose to use it for weapons. I would not expect that the US would, of course, because we already have a massive surplus of weapons materials stockpiled, so even if we were to resume building nuclear weapons, it would be many years before we’d have to worry about making more nuclear weapons materials.

As for other countries and their nuclear aspirations, there’s nothing the NRC can do about that.   If we can do anything about that at all, it will be through diplomatic channels.

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Of all the discoveries of ancient man, none made a greater impact on humanity than fire.  Although fire was certainly developed independently by many groups, its discovery is none the less one of the greatest moments in mankind becoming what we are today.  Without fire there could be no cooking, no warmth beyond what nature or body heat can provide, no light after dark.  Fire was man’s first discovery that allowed the utilization of energy on demand.  It would later drive our engines, smelt our metals and even propel rockets to the moon and beyond.

Anyone who has started a campfire without an accelerate knows that it can be surprisingly difficult to get a good strong self-sustaining flame going, even with the aid of matches or a lighter.  For early man, it was much more difficult still.  Simply being able to consistently create a fire and contain it for use demonstrates a high degree of intelligence and the ability to learn.

Now scientists have discovered evidence that it may have happened earlier than we had previously believed.

Via CBS News:

Humans used fire 1 million years ago, says study
(AP) NEW YORK – When did our ancestors first use fire? That’s been a long-running debate, and now a new study concludes the earliest firm evidence comes from about 1 million years ago in a South African cave.

The ash and burnt bone samples found there suggest fires frequently burned in that spot, researchers said Monday.

Over the years, some experts have cited evidence of fire from as long as 1.5 million years ago, and some have argued it was used even earlier, a key step toward evolution of a larger brain. It’s a tricky issue. Even if you find evidence of an ancient blaze, how do you know it wasn’t just a wildfire?

The new research makes “a pretty strong case” for the site in South Africa’s Wonderwerk Cave, said Francesco Berna of Boston University, who presents the work with colleagues in the Proceedings of the National Academy of Sciences.

One expert said the new finding should be considered together with a previous discovery nearby, of about the same age. Burnt bones also have been found in the Swartkrans cave, not far from the new site, and the combination makes a stronger case than either one alone, said Anne Skinner of Williams College in Williamstown, Mass., who was not involved in the new study.

Another expert unconnected with the work, Wil Roebroeks of Leiden University in The Netherlands, said by email that while the new research does not provide “rock solid” evidence, it suggests our ancestors probably did use fire there at that time.

One thing I have always wondered about, and of course, we will never know, is how many ancients may have learned of fire only to abandon it out of fear. Certainly not all of early man’s encounters with fire were pleasant. It may first have been experienced in the wildfires started by spontaneous combustion of overheated turf or from a lightning strike. Such an experience would be terrifying, and once man began to experiment with fire, it’s all but certain that some mishaps and burns occurred.

Yet some groups stuck with it. Perhaps it was because it was recognized as useful or maybe because it frightened others. Maybe it was just curiosity. Whatever the case, at some point, someone began to create fires and, despite perhaps suffering a few burns or coughing on smoke and enduring the frustration of seeing the tiny smoldering embers go out, they learned how to tame and use fire.

Might there have been some tribes that had mastered fire and others that did not? If so, it’s almost certain that this advantage would have lead to those with fire succeeding and those who didn’t falling by the wayside. This could have even been a factor in early human evolution.

But what i early mankind looked at fire the way we look at new forms of energy today? Would they have used fire at all?  It’s a sobering thought to consider that if our ancestors had the same attitude we have today, we might still be eating raw meat, huddled in mud huts at the mercy of the cold darkness of night…

Here are some of the latest measurements of radiation levels in the Fukushima region of Japan, these were made just last month.

There is something very striking about this image even at first glance.  Notice that the no-entry zone has absolutely no correspondence whatsoever to radiation levels.  It’s simply a circle drawn around the nuclear plant.   Much of the area has quite low radiation levels and some of the area outside the exclusion zone has higher radiation levels than the area within it.  Since there’s now no real danger of the reactors being further damaged or experiencing uncontrolled discharges, there’s absolutely no reason to enforce a no-entry zone based on such a blind method of drawing the map.   If a no-entry zone is to exist at all (which it really, at this point, does not need to)

Actual Doses experienced:

Few areas exceed 20 uSv per hour by very much.  The red area signifies areas with higher than this level, but most of this area is only slightly above 20 uSv/hr.  Areas with 20 uSv/hr or more exist in a relatively narrow strip running northwest from the area of the nuclear plant.

A person lives in an area where the external radiation dose rate is 20 uSv/hr.    Of course, this is really only outdoors and inside there will be less contamination, but for the sake of argument, lets assume the worst:  They get 20 uSv/hr and they stay in that are all the time.  There are 8760 hours in a year, so if they spend all their time outdoors in the 20 uSv/hr area, they receive 175,200 uSv per year or about 175 mSv per year.

This is still a bit unreasonable for what a person would actually be exposed to because it assumes they are always outdoors and standing over ground that has not been in any way cleaned of contamination.  Indoors, the level will be a lot lower.  If they travel outside the area of highest radiation, their dose is also reduced.   As time goes on, both radioactive decay and natural weathering and erosion will reduce levels further.   Therefore, after a year in such an area, it’s more reasonable to expect a total exposure of something like 100-150 mSv and maybe quite a bit less.

Most of the no-entry zone is far bellow this.  The yellow areas would produce only about half the dose of the highest regions and the areas shaded green would result in an annual dose of only about 10-30 mSv her year.  That’s hardly a lot of radiation.

How much radiation a person is exposed to in a year from background sources varies greatly depending on things like location, diet, travel and things like whether they happen to cook with natural gas, live in a granite structure or have radon seeping into their home’s foundation.   About 3 mSv is a normal average for those living at sea level in much of the world.   Of course, it’s quite common for it to be much higher than this.   Areas with background radiation in excess of 10 mSv per year are quite common.  A few areas have much higher.   In the Guarpari region of Brazil, background levels can exceed 175 mSv per year due to local deposits of uranium and thorium.  Residents of Kerala India experience doses of over 70 mSv per year.   Ramsir Iran is famous for having some of the highest levels in the world at over 260 mSv per year.  Locations across Africa and Australia may produce levels above 40 mSv per year.

Studies have been done of the populations of these areas and no ill effects have been documented as a result of the high radiation exposure.   Of course, the expected radiation exposure from living in such an area for an extended period of time would be much higher than for those in the Fukushima area.   Since the radioactivity in the Fukushima region is mostly limited to the surface and includes many relatively short-lived radioisotopes, it will diminish significantly in the years to come.   Natural sources, on the other hand, are constantly replenished.  So a person who lives in an area with increased radiation levels as a result of the Fukushima incident will not experience the same dose next year as they will this year.  It will be less.

And no, there have been no calls that high background areas of the world be evacuated and declared off limits.

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