Is SAR worthwhile and could our choice of radio and TV broadcasting frequencies be killing us and what of 600 MHz for 4G?   


Definitions of present ways of measuring SAR are given.  Disadvantages of the SAR technique are discussed which highlight the fact that due to internal resonances some parts of the body could be receiving far more energy than that defined by SAR and hence either more heating or more bio-effect.  The fact that SAR does not take bio-magnetite into account may also be important.    Causes and types of body resonances to radio frequency radiation are discussed in more detail and in particular with regard to the proposed use of 600 MHz as a frequency for 4G mobile telephony in the UK.  Potential hazards of this frequency to the prostate gland in particular are discussed. Radio frequency radiation, particularly with pulse modulation, as a possible cause of voltage gated ion channel modulation is discussed as is radiation as a bio-growth promoter is also discussed.   Reasons for inconstancies in experiments and epidemiological studies are also visited.  It is concluded that for the moment at least we should always err on the side of caution until we more fully understand humans as ‘beings of frequency’.    In future it may not only be possible to design our communications systems and their siting accordingly but also one day we may be able to develop ‘Startrek’ style ‘tricorder’ units to diagnose us and cure us on the basis of our body response to radio frequency radiation at a cellular level.      



The standard way of defining the safety of mobile telephones and other radio frequency equipment used proximal to the Human body is so called SAR or specific absorption rate.   Specific absorption rate (SAR) is a measure of the rate at which energy is absorbed by the body when exposed to a radio frequency (RF) electromagnetic field; although, it can also refer to absorption of other forms of energy by tissue, including ultrasound.  It is defined as the power absorbed per mass of tissue and has units of watts per kilogram (W/kg). SAR is usually averaged either over the whole body, or over a small sample volume (typically 1 g or 10 g of tissue). The value cited is then the maximum level measured in the body part studied over the stated volume or mass.

Various governments have defined safety limits for exposure to RF energy produced by mobile devices that mainly exposes the head or a limb for the RF energy:

United States: the FCC requires that phones sold have a SAR level at or below 1.6 watts per kilogram (W/kg) taken over a volume containing a mass of 1 gram of tissue.

India: India SAR limit is 2 watt per kg . This is same as ICNIPR guidelines The inter Ministerial Committee of EMF Radiation set up by the Ministry of Communications and Information Technology had suggested stricter SAR Limits (1.6 watt per kg) form mobile handsets.

European Union: CENELEC specify SAR limits within the EU, following IEC standards. For mobile phones, and other such hand-held devices, the SAR limit is 2 W/kg averaged over 10 g of tissue (IEC 62209-1). For Magnetic Resonance Imaging the limits (described in IEC 60601-2-33) are slightly more complicated:


Averaging time

6 minutes

Whole body SAR

Partial body SAR

Head SAR

Local SAR

Body Region

whole body

exposed body part





Operating Mode ↓









2 - 10 (b)


10 (c)



1st Level Controlled


4 - 10 (b)


10 (c)



2nd Level Controlled


>(4 - 10) (b)


>10 (c)



Short term SAR

The SAR limit over any 10 s period shall not exceed three times the stated values


(a) Local SAR is determined over a mass of 10 g.

(b) The limit scales dynamically with the ratio "exposed patient mass / patient mass":

NORMAL OPERATING MODE: Partial body SAR = 10 W/kg – (8 W/kg * exposed patient mass / patient mass)
FIRST LEVEL CONTROLLED OPERATING MODE: Partial body SAR = 10 W/kg – (6 W/kg * exposed patient mass / patient mass)

(c)In cases where the ocular orbit is in the field of a small local RF transmit coil, care should be taken to ensure that the temperature rise is limited to 1 °C.

In comparison to the short term, relatively intensive exposures described above, for long term environmental exposure of the general public there is a limit of 0.08 W/kg averaged over the whole body.

The SAR for mobile phones is generally in the range 0.5 - 1.5 W/kg.


SAR for electromagnetic energy can be calculated from the electric field within the tissue as:


is the sample electrical conductivity

is the RMS electric field

  is the sample density


Disadvantages of the SAR technique.

SAR traditionally measures exposure to electromagnetic fields between 100 kHz and 10 GHz.  One problem with SAR is that the value will depend heavily on the geometry of the part of the body that is exposed to the RF energy, and on the exact location and geometry of the RF source.  For this reason, tests must be made with each specific source, such as a mobile phone model, and at the intended position of use. For example, when measuring the SAR due to a mobile phone the phone is placed at the head in a talk position. Obviously temperature probes can't be placed inside the human body so phantoms are often used to measure SAR.


Such phantoms contain fluids or gels made up with electrical conductivities and densities to try and mirror those of the human body.  However, no such fluid or gel is able to mimic the human body across a substantial frequency range.     Also in the human body there are blood vessels and nerves and layers of different types of tissue as well as internal organs all of which have their own unique dielectric properties.


Another way of trying to estimate SAR is by calculation based on Finite Difference Time Domain Methods and a direct application of Maxwell's equations.   The problem here is whether or not to use a homogenous model where an average dielectric value for all tissue types   used or whether to use an inhomogeneous model comprising layers and dividing the body effectively into cubes. This method requires substantial computing power more so at frequencies less than 50 MHz or greater than 700 MHz where the 3D cell (voxel) size becomes so small that there are many tens of thousands of them to be calculated upon.  Further there are substantial differences whether the body is grounded or not (1).        In a practical situation the ground impedance will highly variable due to clothing, footwear and body position so any calculations, no matter how complex, will not be of much use.    


Another study which has shed light on the use of SAR's relates to the calcualtion of heating of implantable devices during magnetic resonance imaging, where it has actually been shown that using only the whole-body SAR as a recommendation for a safety profile is potentially dangerous, see Nitz et al 2005 (2).


Christ et al (2006) (3) identifies two different effects which can lead to increased SAR in layered tissue in comparison to the SAR assessed using homogeneous tissue simulating liquid and found for larger distances between the tissue and the antenna, standing wave effects occur depending on the frequency and fat layer thickness. This in itself is a pseudo resonance  referred simply to as ‘layering resonance’ which    might give pockets of intense heat absorption at different depths  not unlike that expected due to the notion of quantum mechanical effects proposed elsewhere, see Barnes ( 4  ). Also in the very close near-field (distances approximately lambda/40), reactive E-field components lead to high local absorption in the skin. The latter effect occurs at lower frequencies and depends on the antenna type. In phantom measurement SAR techniques modification of the parameters of the homogeneous liquids employed cannot compensate for these effects. SAR in these cases can be out by up to a factor of 3. Layered resonance effects involving skin, fat and muscle are known which give resonance frequencies in the range 400 MHz to approximately 3 GHz.     


The final drawback of SAR calculations is that they do not include magnetic permeability.  While magnetic permeability of tissue is reckoned to be close to that of the vacuum, there are subtle differences particularly for blood and tissue with a rich blood supply.  The magnetic susceptibility of blood also changes with oxygenation level.  Human tissue particularly brain tissue, especially hippocampus, has recently been found to contain nano-particles of bio-magnetite.    The translational energy of clumps of magnetite exposed to slow time varying fields can exceed typical covalent bond energies (5). This could potentially   account for some ELF effects of even quite weak ( milli-Tesla) magnetic fields or even effects of pulse modulated VHF and UHF radio signals. 


Combining frequency dependent magnetic effects, however small, with frequency dependent permittivity introduces another level of complexity into SAR modelling, which has, as far as the present author is aware, never been attempted.         


It would seem then at best SAR is as good as the model used and being an average gives no notion of potentially dangerous heating at certain biological interfaces within the body in response to r.f.  radiation nor does it take into account internal resonances however caused.  It would seem SAR is presently a comfort factor for licensors and licensees of mobile and wireless technology and due to the enormous complexity of the modelling involved SAR may remain for a while to come yet.  One possible thought, thermal imaging may be a way forward to check RF power deposition. The technique has been used so far only with respect only to MRI fields see Cline et al 2004 (6).        



Resonance external and internal 

The notion of the Human body having a radio frequency resonant point or points is not new.  Yanase and Hirate (2011) (7) calculate effective resistances and resonant frequencies and given the resistance range of between about 50-400 ohms it seems what they show implies to the present author that the Human body might act as a remarkably good antenna in the 40-100 MHz region. This encompasses the original now defunct Band 1 TV broadcasting band, the 6 and 4 metre Ham Radio Bands and the Band 2 VHF FM broadcasting band.  Moving radio frequency fields of even weak and modest field strengths in this frequency range have been seen to elicit motor responses of the hands and arms in humans (8-10).

Energy harvesting implantable bio-chips may be used inside the human body and maintain a certain resonant Q.  Allowing for skin depth, why then cannot a body internal organ or glands, of dielectric property substantially different from its surroundings, behave as an independent dielectric resonator in a similar manner?     Such behaviour has been suggested by the present author elsewhere (4).  For example a good estimate for the resonant frequency of the prostate gland is 600 MHz.  Along similar lines yet at the other end of the scale is indeed an unusual notion that is that the entire blood volume could resonate at a frequency much less than that of the body as a whole!      The brain might resonate at about 200 MHz.  These are coincidentally all frequencies or close to frequencies used for radio and TV broadcasting.

Sophisticated equipment is not needed to prove resonant absorption into human subjects, see Hatch 2012, Ham Radio Blog(11).  

Hatch has shown by using a direct coupled electrode antenna like system on his own body that the body has multiple resonances.

In the above example such resonances are seen at 53,112 and 600 MHz, these are the points of lowest standing wave ratio in the plot. There is a hint of a minor response at about 240 MHz as well.   It is almost bizarre that these are all frequencies that either have in the past or are presently used in the UK for radio or TV broadcasting.    The 600 MHz dip is probably due to a layered resonance effect see above.  Other resonances of separate external body parts so called geometric resonances of head, arms and legs are also possible and are highly position dependent.


In the UK spectrum around 2600 MHz is being or is proposed to be used for 4G.  Others are proposing to use some of the spare former TV spectrum around 600 MHz.  Given the findings of Hatch above and the calculations of Barnes (4) with regard to the prostate gland and inexplicably rising cases of prostate cancer in particular (12,13) Thus  the view of the present author is that we really ought to err on the side of caution.  


o    Safe or not safe?


There exists a simply huge volume of published work on the effects of r.f. radiation. The work has covered in vitro- human and animal cell studies, in vivo animal studies, a few in vivo human studies and epidemiology studies.  Many of these studies have focused in on cancer.  Some conclude that RF has no or little effect while others conclude that RF is a Cancer Promoter rather than a Carcinogen.  Recently the WHO classified mobile phone radiation   as a carcinogen on the basis of the now famous Glioma study (14).  If RF is a cancer promoter then it is logical to assume under the correct conditions it would be a general tissue growth promoter and useful in say wound and bone healing. Thus, not surprisingly, and also recently a new science, so called PEMF (pulsed electromagnetic field) for bio-medicinal therapies seems to have evolved with a sudden surge of related PEMF products available on the market from pain killing devices to local anaesthesia and wound healing (15,16).    


The author has read much of these works and by way of review personally concludes that for whatever reason with r.f in general, digital pulse and a.m. technologies would seem to provoke more biological effects than f.m. and c.w. , particularly  with a view to voltage gated effects such as changing calcium ion efflux (17).   As well as in heart and muscle, voltage gated calcium channels are also found in some cancer cells, see Li and Xiong 2011 and Monteith et al 2012 (18), and play an important role in cancer progression. For example, T- type Cav was found in human prostate cancer and up-regulated during neuro-endocrine differentiation.  The L-type calcium channel subunit has also been found in colon cancer cells. Cav 1.2 expression increases with the differentiation of colon cells to cancer cells. P- and L- type Cav have been found in small lung carcinomas. Calcium spikes, which are caused by unspecified T-type calcium channels and play a role in membrane depolarization, have been shown to alter the motility of fibrosarcoma cells.   


Since PEMF (pulsed electromagnetic fields) are used for bone and wound healing clearly they influence cell division and growth.  There are minimal references in the literature to RF radiation as a cancer inhibitor other than because of thermal ablation but there are a couple of notable exceptions on is (Kalantaryan et al 2011 ) (19) who describe low level coherent millimetre wave radiation as an inhibitor of certain cultured cancer cells in vitro. The other is an animal model cancer study  of Berg et al 2010 (20) which talks of 50 Hz PEMF and SEMF at 15-20 mT  level applied by a solenoid coil.  This is exactly the level of field that is suggested to cause magnetite cluster translational energies to be of the order of those of covalent bonds.  Ion cyclotron resonance effects are yet another possibility.   The author has suggested elsewhere that only with a quantum mechanical explanation can we properly understand the benefits and risks of r.f radiation in general.   This in the author’s opinion is borne out exceeding well by Smith’s reappraisal of the Sutton Coldfield TV Transmitter Cancer Cluster Study (21).  The author has recently created predictive algorithms to show the most dangerous positions for humans and vegetation alike in the proximity of transmitter antennas.  When quantum mechanical concepts are employed, Bayesian statistics will be required to understand geographical effects in epidemiological studies.  Another reason why epidemiological studies don’t always produce expected results is that RF exposure depends on people’s position and mobility.   In the author’s opinion sleeping position and mattress type may also be critical factors.          




The shortcomings of present SAR techniques have been highlighted. Given skin/fat/muscle layering resonances, the resonant frequency and position of the prostate gland (as a dielectric antenna)  and the proposals for 4G in the UK, the author really feels we should be erring on the side of caution.  Based on the available evidence the present view of the author is that RF radiation under most conditions is very probably not a carcinogen but is capable of either accelerating or inhibiting cellular growth.  So if you have a genetic or environmental predisposition and some early stage cancer cells, possibly some       very specific RF frequencies and intensities could potentially speed up their division and growth.  Based on this we should perhaps carefully review our choices of frequency bands in the future.  Human beings evolved prior to synthetic RF but evolved bathed in the earth’s natural field, exposed to DC and slow time varying magnetic fields, Schuman Resonance, Auroral and Meteor signals and solar and galactic generated microwave bursts. Thus human beings are indeed ‘beings of frequency’ this has been recognised in the last century by some the worlds’ greatest of physicists such of Frolich (22) and Herbert Pohl (23).  More recently Smith (24) and Kirshvink (25) have added to the understanding of ‘electromagnetic man’ and indeed all have inspired the present author’s some would say radical (or at the very least diverse) thought in this area.   Today we exploit RF for body scanning in MRI and thermography.   RF can also be used rather indiscriminately in certain forms of thermotherapy or cellular ablation treatment.  Low energy PEMF has been regarded by some as almost ‘quackery’ but there is growing evidence that if the frequencies and PRFS are appropriate then it does indeed work (26). 


Cellular autonomic behaviour has recently shown to be fractal (27).  A new design in antennas using fractal concepts shows multi-specific frequency behaviour (28).  One day we link these two concepts and living beings will no longer be in any danger of external electromagnetic fields for the fields we use will be appropriately chosen and tuned for our protection and indeed even our benefit and indeed some will perhaps by means of voltage reflection measurement become our diagnosticians and our healers conjuring up a vision of Science Fiction’s star trek and Bone’s ‘tricorder’ device (29).  Application of such fields either by external antenna making use of new geometric attenuation principles (4) to dump scalar energy or by injectable  tiny rf devices  might one day be used to time reverse our tired cells a sort of electromagnetic elixir of youth if you will.   Such devices are already so small they can be swallowed e.g. radio pills (30).  It is imagined that just as we on the verge of understanding disease at the genetic and molecular level and designing designer drugs tailored to an individual’s particular genetic makeup hand in hand will they will eventually be given their ideal complimentary quanta of electromagnetic energy as well.                             





1.      Hirata et al 2012.

2.      Nitz et al 2005.

3.      Christ et al 2006.

4.      Barnes 2013.

5.      Strbak et al  2011.

6.      Cline et al 2004.

7.      Yanase and Hirata 2011.

8.      Huttunen et al 2009

9.      Huttunen et al 2011

10.  Huttunen 2012

11.  Hatch 2012, Ham Radio Blog







18.  Monteith et al

19.  Kalantaryan et al 2011

20.  Berg et al 2010



23.  Pohl 1980, ‘Natural electrical r.f. oscillation from cells’

24.  "Electromagnetic Man," Cyril W. Smith and Simon ... C.W. Smith, R.Y.S. Choy and J.A. Monro, 1989.

25.  Magnetite in Human Tissues: A Mechanism for the Biological Effects of Weak ELF Magnetic Fields-