Few days ago, on May 26th, 2021, Martin L. Pall has published review article: ‘Millimeter (MM) wave and microwave frequency radiation produce deeply penetrating effects: the biology and the physics’
Reading this article, what is in fact a serious waste of time for any scientist, I have got an impression that Pall is again talking nonsense. To make sure that I am not mistaken, I have asked two prominent and highly recognized scientists to provide brief opinions on Pall’s review (my own opinion on the Pall’s review will be published next week).
Quirino Balzano: Considerations on Prof. M.L. Pall’s paper entitled “Millimeter (MM) wave and microwave frequency radiation produce deeply penetrating effects: the biology and the physics”
- The very base and the title of the paper are incorrect. The first statement “Electronically generated EMFs are coherent, producing much higher electrical and magnetic forces then (sic) do natural incoherent” is incorrect. The MM wave signals used in wireless communications have extremely complex modulations with wide bandwidths for the rapid transmission of large amount of data. For example, the SC-FDMA (Single Carrier Frequency Domain Multiple access) signals have quadrature phase shift keying (QPSK) as modulation scheme. The other common modulation is the OFDM (orthogonal frequency-division multiplexing). Both schemes have 20 MHz bandwidth, wherein the frequency, the amplitude and the phase of the RF signals are rapidly changing.
- The statement “fixed relationship between electrical and magnetic fields found in EMFs in a vacuum or highly permeable medium such as air, predicted by Maxwell’s equations, breaks down in other materials. Specifically, MM-wave electrical fields are almost completely absorbed in the outer 1 mm of the body due to the high dielectric constant of biological aqueous phases. However, the magnetic fields are very highly penetrating” is fundamentally incorrect. Human tissue has non-magnetic properties and the only characteristics that govern the incident fields’ attenuation is electric dipole relaxation loss. The dissipation of RF energy at MM frequencies is not by resistance to the motion of free charges. Free charges oscillate in place given the frequency of the RF signals
- The hypothesis that the magnetic fields penetrate deeper in tissue than electric fields has no physical foundation. Propagating variable electric and magnetic fields are each other’s source. The magnetic field causes an electric field (and the electric field a magnetic field) throughout the propagation process and all the magnetic and electric field energy is absorbed by the same electric dipole relaxation processes.
- For the reasons given above, the statement “Time-varying magnetic fields have central roles in producing highly penetrating effects” is fundamentally incorrect. If human tissue had strong magnetic properties at MM frequencies, the relaxation of magnetic dipoles, in addition to that of electric dipoles, would cause attenuation in tissue even faster than that mentioned by Prof. Pall.
Given the absence of the physical properties of MM waves predicated by prof. Pall, his biological considerations lack a base of credibility.
Kenneth Foster: Rebuttal to Pall 2021
A full analysis of the many errors in fact, dubious claims and plain sloppy reasoning in this paper would be a big job, and it is not clear that the paper is worth the effort. Some comments:
1. Elementary mistakes in electromagnetics.
- Pall writes: “fixed relationship between electrical and magnetic fields found in EMFs in a vacuum or highly permeable medium such as air, predicted by Maxwell’s equations, breaks down in other materials. Specifically, MM-wave [millimeter wave] electrical fields are almost completely absorbed in the outer 1 mm of the body due to the high dielectric constant of biological aqueous phases…the magnetic ﬁeld permeability which in essentially all biological tissues is very high, producing very high magnetic ﬁeld penetration.”
- This is wrong on two accounts. First, neither air nor tissue are “highly permeable” – both have low magnetic permeability (u = 10-6 H/m). Iron is a high permeability material (u = 0.2 H/m).
- Second, it is an elementary fact of electromagnetics that the electric and magnetic fields in a propagating wave are coupled through Maxwell’s equations. The changing electric field in the wave creates the magnetic field. If the electric field is absorbed then the magnetic field will go away also. The entire premise of Pall’s article, that the penetration depth of magnetic fields from an incident millimeter wave is far greater than that for the electric fields is an elementary misunderstanding.
- In some cases, electric and magnetic fields have a more complex relation, such as very close to antennas (in the reactive near field), or when waves pass through heterogeneous, anisotropic media with strong magnetic characteristics – neither case is relevant to what Pall is discussing.
2. Logical flaws.
- Pall’s discussion of bioeffects proceeds via a series of non sequiturs. Briefly, they are: (a) an investigator reports a statistically significant difference between exposed and control samples in an experiment; (b) the statistically significant result establishes a real effect of exposure; (c) the effect has health significance; (d) the health effect is significant at real-world exposure levels; (e) MY GOD THIS WILL KILL US ALL. In going from step (a) to (b) Pall commits an elementary logical fallacy (the inverse probability fallacy). He also commits major scientific errors by not considering potential errors in the experiment or alternative interpretations of the results. His approach suffers from extreme confirmation bias: he uncritically accepts weak experimental results, overlooks contradictory information, and interprets evidence in the most pessimistic way possible.
3. Misinterpretation of data.
- For example, Pall discusses at length a 2010 study by Pikov et al (his cite 25) as justification for a large reduction in RF exposure limits. That study (which was conducted to explore possible therapeutic effects of millimeter waves) reported changes in the firing rate and other electrophysiological responses of cells in rat cortical slices when exposed to 60 GHz mm waves. The investigators exposed a chamber containing cortical brain slices to millimeter waves at an incident power density of 900 W/m2. They estimated that the exposure to the brain slice itself, at a depth of 2.2 mm beneath the surface of the medium, was 0.01 W/m2. The exposure applied to the chamber was more than 30 times higher than ICNIRP reference levels for the general public at 60 GHz, and the observed effects were accompanied by several degree temperature increases in the medium. Pikov et al. did not claim any health significance of their results but stated “it remains to be seen whether the MMWs [millimeter waves] can produce similar changes in neuronal activity when applied in the human skin and/or central nervous system.” Subsequently, several papers by different authors (e.g., Plaksin et al. Physical Review X. 2018 Mar 16;8(1):011043) considered the effect to be produced by transient heating of the membrane. Whatever the significance of Plikov’s findings may be, the study is very far from demonstrating health risks to humans from millimeter waves at realistic exposure levels.
If Pall concludes that exposure to millimeter waves at ordinary environmental levels is hazardous, he should make his case to scientists and health agencies with scientifically correct and persuasive arguments. This poorly argued polemic will have no effect at all on the understanding of health agencies of the issue.