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Fermi Problem Friday: Sanjay Gupta's Cell Phone Folly

Sanjay Gupta must be smart - for one thing he's doctor, a brain surgeon, in fact. He's also an adviser to Hillary Clinton. And above all, he's on TV! That's why his ignorance about basic physics, along with his eagerness to spread that ignorance, is so troubling.

In this video, Dr. Gupta makes a meager attempt to describe a truly carcinogenic type of radiation known as ionizing radiation, which includes x-rays, gamma rays and other high energy types of radiation. But then he goes about speculating on the dangers of non-ionizing radiation of the type emitted by cell phones. It's guilt by association, and it's just plain wrong.

Listen up, Dr. Gupta, radiation is not inherently dangerous, so please stop using the word like it's a synonym for "toxic." Light is radiation. Radio waves are radiation. You're bathed in both all the time. If you were exposed to high intensities of either, you might catch fire, but they will not give you cancer.

Here's a Fermi problem for Dr. Gupta and the rest of you - what's the worst case scenario for how harmful cell phone radiation might be? I'm sure there are many ways to estimate it. I'll present one calculation on Monday.


  1. Unlike ionizing radiation, the dangers of cellphones have nothing to do with heat or the breaking of ionic bonds that hold all molecules together. Rather non-ionizing radiation from cellphones produces free radicals that disrupt cell membranes, release reactive oxygen species, and at the cellular and sub-cellular level, EMW may exert
    direct or indirect effects on cell membranes, cytoplasm and
    nucleus. Studies conducted by world-class biologists in China, Finland, Israel, and Austrai have shown that exposure to RF-EMW can induce alterations in many sub-cellular mechanisms. Changed plasma membrane potential and calcium efflux with resultant calcium depletion leads to decrease in the activity of
    protein kinase C (PKC). This decrease leads to alteration in many enzymes, ion pumps, channels and proteins as well as inducing apoptosis.
    RF-EMW also induce ROS production through disturbance of the mitochondrial membrane bound NADH oxidase. ROS has impact on PKC,
    histone kinase, heat shock protein, DNA and apoptosis. Heat shock protein (hsp) increases in response to electromagnetic radiation and ROS.
    Hsp slows the metabolism of the sperm and impairs the blood testis barrier, and interferes with apoptosis of damaged and transformed sperm.
    Genotoxic effect of RF-EMW on sperm is either through ROS production or through direct clastogenic chromatin breaking effect.
    An excellent overview of this is provided in Hamada et al, 2011


    1. You should read this article in Wikipedia about ionizing radiation (and the free radicals it can produce)

      It makes it clear why cell phone microwaves are much to low energy, by a factor of about 1000, to create free radicals. If you have a high enough intensity to cook food, free radicals can be produced as teh food essentially burns. But again, cell phones put out about 1000 times less energy than a microwave oven, which is far too little to cook with, and therefore far too little to create free radicals.

  2. How exactly can microwaves create free radicals?

  3. If this is the Hamada et al article you're talking about, I don't see anything in the abstract about microwaves creating free radicals.

  4. For more information about cell phone radiation health risks and our government's inability to forewarn the public due to industry pressure ...

    Cell Phones: Assessing and Preventing Risks

    Cell phone radiation warning on San Francisco government web site

    Cell Phone Radiation Damages Sperm

    54 Health Experts Caution About Smart Meters (smart phones aren't the only concern)

    Does The FCC Plan To Rubber Stamp Outdated Cell Phone Radiation Standards?

    India Adopts Health Warnings & U.S. Mobile Phone Standards

    Russian Cell Phone Standards Offer Better Protection than American Standards

    Magnetic Field Exposure Before Birth May Contribute to Childhood Obesity

    1. You want links?

      "The weight of the current scientific evidence has not conclusively linked cell phone use with any adverse health problems . . .", National Institute of Environmental Health,

      "The majority of studies published have failed to show an association between exposure to radiofrequency from a cell phone and health problems." FDA,

  5. A group of people that all say something stupid doesn't make the thing they're saying any less stupid.

  6. This entire debate over whether or not cell phones are dangerous is getting old. I am not biased, but just stating facts and I have the supporting documentation. Yes, we are bathed in radiation everyday of our lives on this planet and our bodies were designed to cope with this radiation thus we are still alive. However the source of radiation in nature is never found in such close proximity to the body as it is found today and no matter how small the amount of radiation emitted by a device it is still greater than the microwave radiation we receive from the sun. The Soviets during the late 1960's set maximum microwave radiation exposure limit to 0.0010 milliwatts per square centimeter which is still a million times greater than the natural background level of microwave radiation emitted from the sun.

    Here is a short list of organizations and countries that have determined that microwave radiation whether low powered or high causes problems in humans. I'm not saying always cancer, but there is a list of more than 2,300 biological effects. Yes...more than Two Thousand Three Hundred proven effects! These organizations existed before the wireless telecommunications industry and therefore have no political agenda for or against them and I can provide a reference to each source as I have the documentation after years of research. But anyway these credible sources are as follows;
    The United States Navy 2003
    The United States Navy 1973
    The United States Air Force 2003
    Virginia Commonwealth University 1969
    United States Department of Defense Prepared by U.S. Army Medical Intelligence 1976
    U.S. Army Mobility Equipment Research and Development Center 1974
    The Israeli parliament
    Government of India 2012
    Russian National Committee on Non-Ionizing Radiation Protection 2008
    American Academy of Environmental Medicine
    The Country of Switzerland ~2008
    The City of Lyon France ~2008
    The Former Soviet Union 1970

    Back in the 50's and 60's everyone said that there was no link between cigarettes and cancer. This included doctors and scientists. But now we know the truth after millions of people died because of an industry hiding the truth and people not studying to find out the truth. The so called "scare mongers" of the day ringing the alarm about the dangers of smoking were correct. If today's so called scare mongers are correct about the dangers of cell phones, this entire planet will be devastated beyond imagination. As a race of people (the human race) we need to err on the side of caution because there is not a single scientist that can prove that the radiation from cell phones and other wireless devices are safe. Therein lies the problem. A smart man or woman that loves life will do what it takes to preserve that life even if that means communicating the way we did prior to the cell phone becoming popular. Our parents managed just fine and so would we.

    So in closing I prefer that doctors and scientists warn me of possible problems even if there is a small chance of a problem arising. This gives me the opportunity to do my own research and come to my own conclusion. The last thing I want to hear my children say to me is "dad...why did you let me have a cell phone knowing that there were possible dangers? Now I've been diagnosed a result?"

    It's our job to protect our children from harm and if we deny them cell phones and we end up being wrong about cell phone radiation being dangerous...that is ok. I would rest comfortably saying to them "I made a mistake, but I thought that they were dangerous and could cause you harm. I love you and as your parent it is my place to protect you until you can protect yourself and I made what I thought was the best decision at the time."

    Your grown children can do nothing but respect and appreciate your dedication to them and they will show it.

    1. I often have sources of radiation very close to my head. My girlfriend puts out lots of radiation, mostly in the infrared regime, which is much higher energy than microwaves, at intensities nearly a hundred times that of my cell phone. I'm pretty sure snuggling with her on the couch is not going to give me brain cancer. I guess we could commission a study, but I'd rather spend research dollars on science that has at least a minute chance of being useful and interesting.

    2. There are well established, scientific reasons for the toxicity and carcinogenicity of cigarettes. There is no such basis for danger from cell phone emissions.

      You could say "better safe than sorry" except that there are costs that come with being cautious. If the risk is essentially nonexistent then there's no reason to pay the cost that comes with avoiding it.

      I can't prove that gravity will not suddenly fail, and that my children will sail off into space. But the risk is so unscientific, and so unlikely, that I don't plan on tethering my child to the ground, "just in case."

  7. Top cell phone manufactures have already admitted to the dangers of cell phone radiation by filing patents designed to protect users from the radiation emitted by cell phones. To file a patent costs more than $20,000 and no company would file a patent on technology that was not needed or useful. I have included the patent numbers below so that you can see it for yourself. Here are the links to both the U.S. Patent and Trademark Office and the Japan Patent Office.

    Hitachi-Radio telephone set (1991) Japan Patent #3,238,936 "To prevent the health of the user from being injured by providing an antenna to a microphone support. Since…no antenna is placed in the vicinity of the head [of the] user, the head is not exposed by a strong electric field. Thus, the health of the user is not injured."

    Nokia-Radiation shielding apparatus for communications device (1998) U.S. patent #5,854,970. "A device…includes a shielding layer which under operating conditions is between the antenna and the user. The shielding layer reduces electromagnetic irradiation of the user."

    Motorola-Antenna shroud for a portable communications device (2000) U.S. patent #6,166,707. "An antenna shroud used for covering an antenna element…is used to seal the antenna opening in the radio housing and for protecting the antenna element from damage. Additionally, the antenna shroud also is used to protect a user from coming into direct contact with radio frequency energy radiated by the antenna element."

    Ericsson GE Mobile Communications-averaged RF exposure control (1996) U.S. patent#5,524,275. "A radio transmitter output power controller which automatically restricts the maximum transmitting time…A warning signal may be generated to inform a user that the maximum permitted power output is being approached."

    Mitsubishi Electric-Cordless telephone set (1992). Japan patent #4,220,851. "To reduce the effect of an electromagnetic wave onto a head of a human body."

    Siemens- SAR Optimized receptacle for mobile devices (2003) US patent # 7,327,841. "Accordingly, the present invention is directed to a holder for a mobile communication device having a receptacle capable of optimally reducing the SAR value of the mobile communication device secured within the receptacle... to optimally reduce exposure to low level radio frequency energy to an individual carrying a mobile communication device secured within the receptacle.

    There are hundreds of other cell phone radiation shield patents that have been filed around the world. If cell phone radiation was not an issue there would not be any patents filed protecting such inventions at an average cost of $20,000 dollars. How much more proof do you need that the cell phone industry is not telling consumers everything they know?

    1. $20,000 is a small price to pay to cover their behinds legally. Cell companies don't know more about cell phone risk (or the lack of it) than scientists, but they do know what to do to avoid getting sued by ignorant people who incorrectly blame their brain cancer on cell phones.

  8. Higher frequency is often associated with higher penetration power since
    the energy of electromagnetic waves is proportional to frequency. Radio
    waves are relatively low frequency, long wavelength emissions typically
    ranging from a few millimeters to a meter. The visible spectrum has
    higher frequency and shorter wavelengths, ranging from about 400
    nanometers (0.0004 millimeters)to a little over 900 nanometers. The
    infrared spectrum span the region between radio and visible, with
    wavelengths that range from about 1000 nanometers to about 1 millimeter.

    Although infrared wavelengths are shorter than radio, they are still
    quite large as compared to atomic spacing and their energy is still small
    compared with the electrostatic force of the atomic electrons. Therefore,
    both radio and infrared (and visible) interact with matter through its
    molecular structure and macroscopic properties. Radio waves pass through
    walls, this is true, but are slightly attenuated. The chemical makeup of
    the walls permit this - that is they are transparent (or mostly so) to
    radio waves. However, soil in general reflects radio waves. Conductive
    materials also reflect radio waves via the induced currents - hence radar
    works. The infrared behave similarly. Wood contains large carbon and
    water content and both are excellent absorbers of infrared energy at many
    wavelengths. Some materials, like germanium are (mostly) transparent to
    infrared energy. So the pernetration (or lack thereof) of infrared
    radiation versus radio radiation is a consequence of the chemical and
    physical makeup of the medium - not the penetration of high energy
    radiation. It is not until one reaches the x-ray spectrum or gamma-ray
    spectrum that the wavelengths become small enough and energies become
    great enough to interact with the lattice of atomic nuclei which compose
    the wood, metal,... etc.

    You can verify the above and you will see that it negates your last infrared comment. Let's just ignore that one (LOL).

    1. I think we're on the same page regarding a few things.

      As you point out, it's at the higher energies of ionizing radiation (UV light, x-rays, gamma rays, etc.) that photons can cause molecular damage. Cell phone radiation is well below that energy level, and therefor can't do the sort of damage that causes cancer.

      I'm also confident that both my girlfriend and my cell phone bring comparable brain cancer risks - which is to say none at all.

  9. Brain cancer is not the only issue regarding cell phones and human health. There are many others to numerous to name.

    Again. It's not the radiation itself, it's the digital data that rides on top of it that causes the problems.

    1. If they are too numerous to name, could you give us a sample of perhaps 3? I'm also curious what "digital data" is when separated from its transmission medium. Your DNA consists of is chock full of As, Cs, Gs, and Ts which are digital data just as any other non-analog data. Is DNA dangerous?

    2. Based on simple signal issues, the highest frequency data that can be transmitted on a wave is half the frequency of the carrier frequency, and most data comes at much lower rates than that. Also, all signals can be represented by a sum of sine waves. So the data on the microwave cell signal is at best half the frequency and half the energy of the base microwave carrier. That makes the data even less detrimental than the microwaves themselves - at least physically speaking.

      The content of the data may be harmful, I suppose, but only in the sense that it's telling you something that hurts your feelings. For example, if your significant other texts you to say it's over, your brain cells are safe, but your psyche may be pretty messed up.


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