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 20 June 2013

Why You Cannot Build a Nuclear (Fission) Reactor At home

June 16th, 2013

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What a nuclear reactor is:

In order to continue, it is important to first qualify exactly what a nuclear reactor is.  In some sense, one could consider any device in which a nuclear reaction occurs to be a reactor, regardless of the type of reaction.   By this definition, combining an alpha emitting isotope with aluminum or beryllium would be a nuclear reactor, since some of the particles will be absorbed and produce a simple nuclear reaction.

Within most context, however, the term “nuclear reactor” is understood to mean a fission reactor.  That is, a device which produces a sustained fission chain reaction using a material like uranium or plutonium.  This normally means that the reactor must achieve critical mass.  However, fission can also be achieved in a sub-critical mass by producing neutrons from an external source such as an accelerator in what is known as a subcritical reactor.

Nuclear fusion reactors are completely distinct from nuclear fission reactors.  Although a nuclear fusion reactor could be called a “nuclear reactor,” doing so, without qualification, is likely to cause confusion.  Nuclear fusion reactors come in a variety of types and it is possible for advanced amateurs to build simple electrostatic fusion reactors, such as the Farnsworth Fusor using commercially available materials.   While these fusors are indeed true fusion reactors, in that they can produce nuclear fusion, the amount of fusion they produce is very small and the neutron radiation generated is low enough to make them relatively safe to operate.   They do not require any radioactive materials for construction or operation.

Once in a while you will see a story in the news about an amateur building a “nuclear reactor” for a science fair or demonstration.   This generally means that they have constructed a fusion reactor, usually in the form of a Farnsworth Fusor.  While doing so is certainly an accomplishment and a very advanced amateur science project, it is not a “nuclear reactor” in the sense of a fission reactor.   It produces no usable energy and only limited neutron flux.

Building a fission reactor is something else entirely.

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Posted in Bad Science, Misc, Not Even Wrong, Nuclear

MAJOR DECISION: US Supreme Court Rules Human Genes Can’t Be Patented

June 13th, 2013

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In a major decision that is sure to have enormous effects in the United States and beyond, the US Supreme Court has ruled that human genes are not patentable.  The Court rules that the genes are naturally occurring and therefore a discovery, not an invention.

This decision does not directly impact artificially inserted or manipulated genes, as in genetically modified organisms, but it is likely to have major impacts on both human and non-human genes in the fields of testing screening for diseases or conditions. Although the case deals with human genetics, the language of the decision seems to make it apply to all genes that exist in an organism in nature.

Although this is only applicable to the US, it is an important precedent that may well effect other countries. If nothing else, it will certainly change how companies go about protecting or attempting to protect their discoveries, if only because the US is such a huge market.

Via the New York Times:

Supreme Court Rules Human Genes May Not Be Patented
WASHINGTON — Human genes may not be patented, the Supreme Court ruled on Thursday. “A naturally occurring DNA segment is a product of nature and not patent eligible merely because it has been isolated,” Justice Clarence Thomas wrote for a unanimous court. But manipulating a gene to create something not found in nature is an invention eligible for patent protection.

The case concerned patents held by Myriad Genetics, a Utah company, on genes that correlate with increased risk of hereditary breast and ovarian cancer.

The central question for the justices in the case, Association for Molecular Pathology v. Myriad Genetics, No. 12-398, was whether isolated genes are “products of nature” that may not be patented or “human-made inventions” eligible for patent protection.

The patents were challenged by scientists and doctors who said their research and ability to help patients had been frustrated.

The court’s ruling will shape the course of scientific research and medical testing, and it may alter the willingness of businesses to invest in the expensive work of isolating and understanding genetic material.

After much thought, I have to say that I agree with the court. The reason is that the detection of a given gene for something like breast cancer risk or another condition is not itself a unique procedure, but rather it is common genetic sequencing with a knowledge of the existence of that gene. In other words, if the gene could be patented, then any genetic laboratory would still be able to “see” the gene any time they sequence the genes of a human subject, but they would be either required to not look at that piece of chromosome or not report that the gene was detected, at least not without paying a royalty or license fee.

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Posted in Bad Science

New Clues in Colony Collapse Disorder

June 12th, 2013

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Colony Collapse Disorder has been reported on here before.   It’s a recent and disturbing trend that has been seen in numerous places around the world in which honey bee populations abruptly plummet as hive colonies “collapse” and die out.  The implications are worrisome, since bees are important pollinators for food crops.

There have been numerous causes proposed for colony collapse.  Many are fringe or just ridiculous.  The chemtrail/haarp/depleted uranium/fluoride conspiracy theorists seem to love using colony collapse as a way of proving that the government must be spraying something horrible in the skies or transmitting evil energy waves.  Another popular hypothesis is that colony collapse is caused by electromagnetic pollution from cell phones, wifi and other devices.   Of course, there is no evidence at all that this is true, and, in fact incidence of colony collapse seem to have no coloration at all to the prevalence of RF transmitters.   Still others have blamed the use of genetically modified organisms, although, again, the patterns of collapse do not relate to where genetically engineered crops have been used.

More mainstream hypothesis are that it is related to parasites, such as viruses or fungi.  Pesticide use has also been suggested as a contributor, this remains controversial, and, as one might imagine, many will jump on any information about pesticides and make outlandish claims.   It’s possible that insecticides do play some roll in stressing colonies, but they are clearly not the primary factor, though possibly a contributing one.

Despite the consensus that parasites play a major roll in colonies collapse, this does not explain why it has been increasing around the world in recent years.

However, a new hypothesis may explain what is causing the increase in CCD

Via Ars Technica:

Feeding bees corn syrup may leave them vulnerable to colony collapse
Apis mellifera, the western honeybee, is big business; the pollination services the bees provide to US agriculture are valued at roughly $14 billion. Unfortunately, bees the world over are suffering from colony collapse disorder (CCD), in which worker bees go out foraging and then disappear instead of returning to the hive and tending to the queen like they are supposed to. The causes of CCD are not clear, but pathogens, parasites, and pesticides have all been implicated. Neonicotinoids, a class of pesticides that have been shown to alter bees’ navigation, foraging, communication, and reproduction, have just been banned in Europe in an attempt to help the bees.

New research suggests yet another potential contributor to CCD. The problem? We’ve been stealing the bees’ honey and instead feeding them high fructose corn syrup. The problem isn’t so much the fructose as the absence of chemicals in the honey.

Commercial beekeepers feed bees high fructose corn syrup instead of honey for the same reason that commercial food manufacturers feed it to us: it’s cheaper. But it’s only one of the problems the bees face. In the 1980s the varroa mite, Varroa destructor, started attacking bees in the US, so pesticides were introduced into beehives to kill the mites.

When I first saw the headline for these stories, I was skeptical. After all, HFCS has been blamed for everything from cancer to obesity, despite the science indicating its no more harmful than any other form of sugar. However, in this case, the problem really has nothing to do with High Fructose Corn Syrup, but rather is related to the practice of using a honey substitute to feed bees.

High Fructose corn syrup is the most common feed used for bees in the US, since it is cheap and available. Elsewhere, glucose syrup or other sugar syrups are used. The bees produce honey, which is used to feed larva and as a source of stored food for the colony. In nature, this is what the bees would live on. However, since one of the major reasons for keeping bees is to harvest the honey, bee keepers have routinely been removing honey and replacing it with other sugar syrups, allowing more of the valuable honey to be collected.

While the substitute sugar syrups are not themselves harmful, it’s long been established that honey has antimicrobial properties and contains traces of environmental chemicals from the area it is collected. Both of these features can be important, protecting the larva from microbial pathogens and helping build the immune systems of bees. In some ways, this is analogous to the proven benefits of breast milk.

While this hypothesis still remains unproven, it is very much worth considering.  Despite the claims that it’s HFCS that is causing the problem, it’s really the absence of honey that is at issue, which is a much more reasonable explanation.


Posted in Bad Science, Culture, Enviornment, Good Science

Setting the Record Straight On Radiation Experiments

June 8th, 2013

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In the 1940’s and 1950’s, the United States government undertook a large number of experiments involving radiation, radiotoxicity and nuclear safety.  While most of this research was done within reasonable ethical standards, using animal models, tissue cultures and occasionally human volunteers, it is known that there were some experiments which involved human test subjects and which did not meet even the most basic standards for ethics.

The most infamous of these were the plutonium injection experiments.  Test subjects were injected with solutions containing trace amounts of plutonium in order to aid in the development of plutonium exposure tests.   Six employees at a Manhattan Project site were given water with small amounts of plutonium in order to determine how it would be absorbed in the digestive tract.   In one case, pregnant women were given what were called “vitamin drinks” in order to study how radioisotopes were transferred to the fetus.

These tests may not have included full disclosure to the test subjects.   It is still important to note that the levels present were bellow those which were supposed to be harmful.  None the less, the potential for harm existed, and today there is no question that the experiments would be considered unethical.

More about these disturbing experiments can be read here.

While we should not deny the existence of experiments of this type, it is also important not to exaggerate them.   Unfortunately, those who see this as some kind of reason to oppose nuclear energy have done just that.   Critical examination of many of the claims put forward show that there is much less to it than has been suggested.

Via City Watch:
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Posted in Bad Science, Good Science, History, Misc, Obfuscation

No, Agent Orange Is Not Being Used On Turkish Protestors

June 2nd, 2013

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Unless you have been living under a rock the past few days, you are probably aware that there have been massive protests in Turkey.  These protests have, unfortunately, turned violent, largely as a result of the government’s actions to try to suppress them.  The protests started over urban development projects but quickly grew into general protests against the government and the current prime minister, Recep Tayyip Erdogan, who is viewed as authoritarian. Police responded with massive amounts of tear gas and anti-riot teams.   Although the protestors have caused damage, including setting cars on fire, the general international response has been to view the Turkish authorities as reacting in a manner that is unnecessarily harsh and violent.

That said, one thing they are not doing is spraying the protestors with agent orange, despite some reports of this happening.

Via the Saint Louis Post Dispatch:

St. Louis, MO – Demonstrators will gather to proclaim their support for the victims of brutality in the protests happening throughout Turkey tomorrow, June 2nd, at 6 pm, at the Gateway Arch.

Protestors are allegedly being attacked with Agent Orange, high pressure hoses, and teargas as they protest the current government’s policies and actions. Amnesty International has condemned the use of “excessive force” against the protesters, and the US State Department offered support of these peaceful protesters.

This is not the only news outlet to report this.   Sadly, it seems reporters are not even willing to hit up Google or Wikipedia before writing something that does not even make any sense.

Agent Orange was one of the “Rainbow Herbicides” used by the US military during the Vietnam War.  It is composed of n-butyl esters and was used for the purpose of defoliating jungle in order to deny enemy forces cover.   Huge volumes were sprayed over Vietnam in order to kill vegetation.  It was later used in a program to destroy food crops that were being used by enemy forces and to try to force local populations to leave rural areas and urbanize.

Agent orange is not itself very toxic to humans or other mammals.   If properly formulated, the mixture is quite safe to handle.  The problem that arose with agent orange is that, as the war dragged on, the military demanded larger and larger volumes of the herbicide, and in order to fill the demand, quality control at the contractors that produced it began to fall. As a result, many of the batches of agent orange were heavily contaminated with 2,3,7,8-Tetrachlorodibenzodioxin, an especially potent dioxin. Dioxins are a byproduct of producing agent orange, and will not be present in the output stream, if scrupulous quality control measures are followed. Unfortunately, they were not.

The quantity of dioxins in agent orange was normally not enough to cause acute effects, as only massive dioxin doses will do so.   The danger came from chronic exposure.  Dioxin and dioxin like compounds are potent carcinogens and are associated with birth defects.   Studies have shown an increase in the rate of Parkinson’s disease in those exposed, amoung other conditions.

But all these effects happen years, sometimes decades later.  Hosing down protestors with the stuff would do absolutely nothing.   Some of them would get cancer in ten or fifteen years and many of their offspring would have major birth defects.  That hardly seems like a useful way of breaking up a protest.

If that does not make the accusation absurd enough, it’s also worth noting that agent orange has not been manufactured in decades.  It was used primarily in Vietnam, although some agent orange may have been sold or used elsewhere, such as in Brazil.   Regardless of where it may have been used, surplus stockpiles were destroyed by the end of the 1970’s and none is currently in production.

While the Turkish government may be spraying the protestors with some unpleasant substances, rest assured, it’s not agent orange!


Posted in Bad Science, Not Even Wrong, Politics

Could the Tide Be Turning on Anti-GMO Groups?

June 1st, 2013

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Genetically Modified Organisms may be one of the greatest single achievements of science of the late 20th century.  In addition to providing better crops, they can produce unlimited amounts of human clotting factor, insulin and other compounds needed by medicine.

As far as food crops go, there is absolutely no reason to think they are dangerous or unhealthy and volumes of scientific data to prove they are perfectly safe.   Like conventional crops, genetically modified food crops are made of the same basic materials: water, salt, cellulose, sugars, proteins etc.   The genes may be slightly different but your body certainly doesn’t care.  And while it is possible that introducing new genes and thus proteins could cause allergic reactions, this has been accounted for in all tests and no reports of mass incidents of allergic reactions have occurred.

Most modern farmers purchase their seeds from seed companies, which provide a more consistent product than producing their own seeds.  Hybridized and specially bred varieties are available and may cost more, but also offer benefits.   Genetically modified seeds fit into this business  model as do any other type of seed.

Despite this, activists have gone nuts over this technology.  Many have demanded that the crops are not fit for human consumption, must be banned and blame them for everything from obesity to cancer, despite lack of evidence.   Fields have been burned or mowed down, protests have been held across the world.  Efforts often center around the company Monsanto, which is he single largest producer of genetically modified products.  Monsanto only accounts for about a quarter of products currently available.   It’s the company everyone seems to love to hate, but that does not make its products unhealthy or unsafe.

The extreme activism and political pressure has resulted in a few jurisdictions severely restricting or banning genetically modified crops.  It has even lead to famine-stricken regions refusing food aid on the basis that it might contain genetically modified material.

Yet the tide now seems to be starting to turn, at least slightly.  A few prominent environmentalists and humanitarians are stepping up to the plate to denounce the knee-jerk fear of genetic engineering.

This article from the Daily Kos has recently been getting a great deal of attention:

GMO Truthers need to be kicked out of the Progressive movement

I consider myself to be part of the “far left.” I also have multiple scientific degrees and work in the health care field. I strongly believe that my science background has resulted in my Progressive ideology. The reason being is Progressivism is a fact and science based ideology, whereas Conservatism is a faith based ideology. Conservatives offer religious, faith based solutions to social problems. Moreover, they rely on faith in the “invisible hand” for solutions to the economy, and any free market outcome – whether good or bad – is a moral outcome regardless of its practicality. Hence, wanting to let the economy hit rock bottom after the financial crisis, because that was the “moral”/free market thing to do.

Why do I bring this up? Because a biologist recently wrote a diary criticizing the far left for being a home for GMO truthers. And, unfortunately, Meteor Blades recently promoted GMO nonsense on the front page.

I would probably say that most progressives don’t know much about GMO at all because this topic – especially the science behind it – is not discussed nearly as much as something like climate change or evolution. And this is perfectly all right! It is impossible to know everything about everything. You know GMO has something to do with big corrupt corporations (i.e. Monsanto) and there are a lot of people and groups you inherently trust who say GMO is bad, so you are naturally inclined to think of GMO as a negative thing.

It’s worth a look and I certainly hope it continues to get attention. The comments are predictable, unfortunately. There are a few who are standing up for reason, but many are still in fear of GMO’s.

Politics aside (and I would not consider myself to be part of the fart political left or modern progressivism in general) it is great to see this major segment starting to show some backlash against the GMO fear-mongers.

Political philosophy, after all, is a matter of value judgements and is not fallible. Everyone is entitled to their opinions and there’s no way to prove whether one ideology is right or wrong. But everyone is not entitled to their facts and the safety of GMO’s is an issue of scientific fact. Either you agree with it or you are wrong.


Posted in Agriculture, Bad Science, Culture, Enviornment, Good Science, Politics

This Month In Radiophobia

May 30th, 2013

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We all know that radiophobia is rampant. Every time there is even a hint that someone might get exposed to some ionizing radiation, the media goes nuts. It seems like it’s the latest thing to write “studies” pegging cancer risk to medical x-rays or using the wrong kind of tile grout. Just for fun, I wanted to see how many news stories which qualify as “radiophobic” I could find for one month. Here’s what I found in the media, for May 2013:

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Posted in Bad Science, Culture, Misc, Nuclear, Obfuscation, Politics, media

High School Chemistry Demonstration Gone Wroing

May 21st, 2013

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One of the great benefits of the proliferation of cameras on phones and devices is that so many wonderful events of every day life are not captured and uploaded to the internet.

Here’s a great one from a high school chemistry class.

Now I’m all for hands-on learning, because it shows how science can be fun and helps demonstrate basic principles.   I’m not sure exactly what they are demonstrating here, but I’m guessing that it’s the fact that methane gas, the primary component of natural gas is both lighter than air and flammable.

What could possibly go wrong?    My first concern would be that they could inadvertently set fire to the ceiling.   Hanging ceiling tiles are supposed to be fire resistant, but that only means they will usually char slowly and self-extinguish.  They can still, under the right conditions, catch fire, and there are exampled of hanging ceilings that, for whatever reason, did not seem to meet the standards for fire resistance.   Hence, given the low elevation of the ceiling and the potential to start a fire, I would not consider this an entirely safe demonstration.

Thankfully, that did not happen.   However, something even funnier did…


I have no idea whether the teacher kept his job. My guess would be that he did, since teachers unions tend to be quite protective and he didn’t seem to have done anything overtly indefensible. (like an inappropriate relationship with a student or stealing from the school) But regardless, it’s pretty certain that he had some real egg on his face after this, and that by the time they got to the valve to shut down the sprinklers, there was a pretty huge mess to clean up and some substantial water damage.

One should remember that as far as chemistry demonstration mishaps go, many have gone far worse than this one!


Posted in Bad Science, Education, Humor, Misc, media

The Truth About Energy Drinks

May 20th, 2013

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Recently, there has been a lot of controversy about so-called energy drinks.   These are caffeinated drinks sold as energy boosters.  They may be carbonated or uncarbonated and can be found at just about any convenience store or gas station.   Many come in large-sized cans, but an increasing number are of the “shot” variety, coming in a single small bottle or can that can be downed in just about one gulp.

VIA CBS NEWS:

San Francisco sues Monster for marketing energy drink to kids
A fight between Monster Beverage and San Francisco’s city attorney is intensifying. The city attorney is filing a lawsuit against Monster Beverage Corp, the maker of Monster Energy Drinks, accusing the company of marketing to young children.

City Attorney Dennis Herrera said Monday that Monster markets it highly caffeinated drinks to children as young as 6 years old, despite scientific findings that such products can cause health problems including severe cardiac events.

The lawsuit comes after Monster last week sued Herrera over his demands that it reduce the caffeine levels in its drinks and stop marketing to minors.

On Monday, Herrera noted that his office had been working with Monster in “good faith to negotiate voluntary changes” when the company abruptly filed its lawsuit.


New York’s attorney general has subpoenaed energy drink makers including Monster about how the drinks are made and marketed, and Democratic Senators Richard Durbin of Illinois and Richard Blumenthal of Connecticut have repeatedly called on the Food and Drug Administration (FDA) to look into the safety of the drinks.

Monster has been in the spotlight since October 2012, when the parents of 14-year-old Anais Fournier of Hagerstown, Md. sued the company after their daughter went into cardiac arrest after drinking two of popular energy drinks in 24 hours.

The FDA said in Oct. 2012 it was investigating five deaths and one heart attack linked to Monster Energy Drinks dating back to 2004. One can contains about 240 milligrams of caffeine.

The company denied its drink’s role in the girl’s death in March, with company lawyer Daniel Callahan telling the Associated Press at the time that physicians hired to review the girl’s case determined she died from natural causes, brought on by pre-existing heart conditions.

Oh great, my own Senator, Dick Blumenthal is now getting himself involved. In fact, Blumenthal does not just think that the drinks should not be marketed directly to minors, he actually has suggested that an ID be required to buy them, making them only available to those over 18. Presumably meaning they be kept behind the counter and being subject to carding like cigarettes and alcohol. (Sorry, I do not have a citation for that, as I heard this when he was speaking on a radio interview.)

There are a couple of problems with this:

  1. Energy drinks, for all the hype are really nothing more than caffeinated beverages.   What makes an “energy drink” different than something like Coca-Cola or Pepsi is arbitrary.  Many have more caffeine than common sodas, but some don’t.  In general, all have much less caffeine than coffee, which, could legitimately be marketed as an energy drink, but usually is not.
  2. There is no evidence that would indicate that there is anything especially dangerous about energy drinks.  It’s true that they are not very nutritious as far as foodstuffs go.  They’re loaded with sugar and their claims of having beneficial vitamins and enzymes are, at best dubious, but that does not make them any worse than any other soft drink.
  3. The amount of caffeine in energy drinks is not so high as to preclude one from getting an equal or greater dose of the stuff from other means.  In other words, if you are going to go after energy drinks, you had best be ready to go after a large portion of soft drinks out there.

The example of Anais Fournier is certainly unfortunate, but there’s no reason to think that two Monster Energy Drink.   Based on the reports, she apparently drank two of the drinks over the period of 24 hours.   That means she had about 320 milligrams of caffeine during that period of time.

There is a great deal of hype over energy drinks, what they do and what active ingredients they may contain.   The truth is that, for all their claims of providing lasting energy from enzymes, vitamins, minerals, or some other special compound, they all work in exactly the same way that “energy drinks” have been working for centuries.

Although caffeine, the active ingredient in energy drinks was not isolated until 1820, the stimulating effects of caffeine-containing plant material, such as coffee beans, tea leaves and kola nuts had been known since antiquity.

Brewed coffee, which became popular across the Middle East and Europe in the 1600’s, remains one the largest sources of caffeine.  And, overall, brewed coffee is at least as potent a caffeine source as most energy drinks.

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Posted in Bad Science, Culture, Misc, Politics

Eleanor R Adair – 1927-2013

May 18th, 2013

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The name probably does not sound familiar, but Dr. Eleanor Adair should be remembered as one of the most important figures in advancing our understanding of the health effects of microwave radiation. She did some of the first controlled large-scale trails on humans, including herself, which helped establish the thermal effects of non-ionizing radiation.

As it turns out, I also live in the same town where she did, but sadly I did not know this until after her passing.


Obituary Via the New York Times:

Eleanor R. Adair, Microwave Proponent, Dies at 86

Eleanor R. Adair, a scientist who spent decades exposing monkeys and eventually people (including herself) to microwave radiation to determine whether it posed serious health risks — she concluded, emphatically and somewhat controversially, that it did not — died on April 20 in Hamden, Conn. She was 86.

The cause was complications of a stroke, her daughter, Margaret Adair Quinn, said.

In the early 1970s, Dr. Adair, who had done her doctoral work in sensory psychology, was pursuing an interesting but not necessarily provocative topic: how people and animals react physiologically to external heat sources. Yet over the next three decades — after her research led her to study heat generated through microwave radiation, which is used in microwave ovens and emitted at low levels by things like cellphones and electrical transmission lines — Dr. Adair became an increasingly prominent and firm voice of assurance that microwave radiation posed no health risk.

“All the emphasis that we need more research on power line fields, cellphones, police radar — this involves billions of dollars that could be much better spent on other health problems,” Dr. Adair said in an interview with The New York Times in 2001. “Because there is really nothing there.”

For some people close to the issue, those were fighting words.

Even as numerous studies have found that microwave ovens are safe and many scientists say there is no evidence that cellphones cause cancer or other health problems, the rising use of cellphones, wireless Internet signals and some medical and military devices has continued to raise questions about their risk. Last year, a panel of the World Health Organization listed microwave radiation as “possibly carcinogenic.” In March, the Federal Communications Commission announced that it would review its standards for cellphone use for the first time since 1996.

Some scientists do not use the term microwave radiation because they are concerned it is misleading and scares people unnecessarily. Microwave radiation is far weaker than the radiation in X-rays or gamma rays.

Advocates for more research count Dr. Adair in to a camp that focuses too much on heat or thermal effects from microwaves and is too quick to dismiss other ways microwaves might affect health.

“There’s something going on, and the question is what that is and whether it’s dangerous,” said Louis Slesin, the editor of Microwave News, a Web site that is often skeptical of the role industry and the military play in influencing health standards related to the issue. “Don’t let anyone tell you they know the answer to that question.”

Although Dr. Adair said she did not receive money from cellphone makers or industries whose products released microwave radiation, she served for five years late in her career as a senior scientist at the Air Force Research Laboratory in San Antonio. The Air Force uses radar that emits microwaves.

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Posted in Good Science, Misc, inverse square