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Report on The Third International Conference - Electromagnetic Fields
and Human Health. Fundamental and Applied Research. September 17-24,
2002. Moscow-Saint Petersburg, Russia
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RADIO FREQUENCY ELECTROMAGNETIC FIELD (RF EMF) STANDARDIZATION FOR THE RUSSIAN POPULATION. RETROSPECTIVE RESEARCH AND THE MODERN VIEWPOINT
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Grigoriev Ju.G.1, Shafirkin A.V.2, Vasin A.L.3
1 SRC RF - Institute of Biophysics at the Ministry of Health of RF,
Moscow, Russia
2 SRC RF - Russian Academy of Sciences, Institute of Medico-biological problems, Moscow, Russia
3 Center of Bioelectromagnetic Compatibility, Moscow, Russia
The unique aim of our report lies in our wish to reconstruct for you the
history of EMF standardization in the USSR, system of this process
organizing, conducting of corresponding experiments and finally to
present you with the main factual material taken into consideration
in standardization. In this connection we have provided you with
a supplement in English in the form of charts with basic parameters of
experiments.
Already in the 1970s the Ministry of Health Protection, Council of Ministers of
the USSR, Ministry of Defense paid great attention to the problem of EMF
biological effect research, considering its effect on human health both
in professional conditions and on the population as a whole. In our report
we will concentrate only on the radiofrequency EMF range.
Researches were carried out in several directions at the same time
according to the scheme on picture 1:
- study of EMF biological effect mechanisms;
- study of EM acute and chronic effect in experiments;
- hygienic evaluation of working conditions in manufacturing connected
with EMF effect and showing up of professional pathology development
features;
- analysis and summarizing of received data and working out of
sanitary rules (EMF standards) for professionals (controlled
terms) and population.
Conducting of EMF biological effect research (EMF biological effect
mechanisms study, analysis of bioeffects under acute and chronic
influences, hygienic research and working out of RF EMF standards) was
commissioned to hygienic institutes in Kiev, Kharkov, Leningrad and
Moscow, Military medical academy, Central aerospace institute at the
USSR Ministry of defense, Institute of medical radiology of the USSR
AMS, USSR AS Institute of Biophysics and Institute of Biophysics at the
USSR Ministry of Health Protection. These institutes had been funded for
fifteen years.
Special interdepartmental problem commissions, problem commissions of
USSR AS, USSR Ministry of health protection and USSR Academy of Medical
Sciences and Commission of military-industrial establishment exercised
control over this research. The research results were regularly discussed in
different scientific and administrative forums.
I would like to emphasize especially that there was no spontaneity in
studying this problem in the USSR. It is important to recognise that some parts of
these complex researches were analyzed, summarized and represented in more
than 100 Ph.D. and doctoral theses that preliminarily underwent a
thorough approbation and control of the USSR Supreme attestation
commission after presentation.
Among the leaders of problem research on EMF biological effect were
academicians: Letavet, M.G. Shandala and L.A. Iljin and also professors:
Ju.D. Dumansky, Z.V. Gordon, A.G. Subbota, I.G. Akoev, B.I. Davydov, and
Ju.G. Grigoriev.
Already in the 1970s we had rather convincing data confirming the existence
of steady biosystem reactions, including whole organisms, on low
intensity EM acute influence (less than 1 mW/m2).
The theme and agenda of the "round table" do not allow us to consider in
detail the results of these researches. I would like only to state that
results of previous experiments with acute EM-irradiation were taken
into consideration in the planning of chronic experiments, analysis of the
received data and in the consequent development of standards.
Furthermore results of hygienic research were used as basic materials
(working conditions evaluation, establishing of the so called
professional route, data on repeated clinical-physiological examinations
of professionals comparing with corresponding control groups). Upon
request of L. Kheifets some results of hygienic research will be
represented in reports of doctors L. Tomashevskaya, V. Nikitina and N.
Rubtzova, though it was not planned to report on the results of this
research direction (hygienic research data) at this "round table".
Allow me to turn to the main topic of the "round table": results of
chronic experiments with low intensity RF EMF conducted in
the 1970s.
We picked out twelve experiments on the evaluation of RF EMF influence on
immune system. They are all combined by unified conditions of
irradiation execution, chosen tests and approaches to the results
evaluation.
Before starting to give an account to the results of these experiments I
would like to point out the preliminary research work that preceded the
conduct of experiments with chronic RF EMF irradiation of animals and
also the methodological part connected with EM-influence providing in
these experiments.
I think it necessary to draw your attention to the fact that
mathematical planning of experiments preceded conducting of numerous
chronic experiments with EMF with a view of standardization in the USSR.
Corresponding publication is represented for your attention:
"Mathematical planning of experiments in EMF biological evaluation" (See
Appendix 1). Three tasks were formulated in this publication:
1) to randomize as much as possible the conditions of
experiment conducting with the aim to reduce inaccuracies;
2) to receive in each test a polynomial model of the studied factors
effect for their comparative evaluation from the viewpoint of reproducibility, sensibility and definition of factor ranges;
3) to define inoperative level by calculated method in the
received levels with the aim of EMF hygienic regulation.
It was also recommended in this work to use blinding.
Experimentalists didn't know as a rule, to what level of factor
influence certain animals were exposed. The leading executor conducting
a certain experiment didn't study the tests but had all information.
Report "Modeling of irradiation conditions in anechoic chambers and evaluation of absorbed energy in conducting of biological-hygienic
research" (Djachenko et al) was presented at the USSR AS scientific
conference (Pushchino, 1982). These materials were published more in
detail in the leading hygienic magazine "Hygiene and sanitary" (_ 10,
1985, pp.40-43). The report extract and article text are given in App. _
2. The irradiation was conducted in anechoic chambers in the area of
shaped field. It is known that anechoic chamber effectiveness depends a
lot on what materials absorbent is made of. Thin-layer material based on
ferrite was chosen as such material. Its working frequency range was
0,3-15 GHz under reflection coefficient 1-3 %. Chamber size was 2,5 x
2,5 x 2,5 m, that allowed to place animals in the area up to 3 m2 under
upper irradiation in 10% field inhomogeneity.
Good condition parameters of animal keeping were created in anechoic
chamber (temperature, humidity and air exchange speed). These parameters
had been kept during experiments for many months.
All irradiation conditions and dosimetry results were also published in
detail in a hygienic magazine (Appendix 3).
Retrospective evaluation of experimental research on RF EMF
influence on immune system (Results of twelve chronic experiments were taken
into consideration in the development of standards in the USSR)
Immunological criterion for harmfulness evaluation was declared the
theoretical and method base of EMF standardization by Soviet sanitarians
in the 1970s. (Vinogradov G.I., Hygiene and sanitary, 1984, _4, pp.4-6).
It was noticed that EMF influence negatively on nonspecific protection
factors. It is the opinion of professors N.N. Klemparskaya 1972 (IBPh
MHP), Vinogradova G.I. 1984,1987 (Kiev scientific-research institute of
general and communal hygiene) that the role of autoimmune autoallergic
organism reactions in biological activity evaluation is great both under
ionizing and non-ionizing radiation.
It's known that autoimmune reactions development is connected with the
fact that antibodies or sensibilized lymphocytes directed against their
own tissues are generated as a response to the changed albuminous
structures.
Immune system normally provides constant functioning of natural
immunological tolerance - that is one of the main conditions of existence
of the organism as an integrated system. Protection function failure leads
to the situation when specific immune reaction is directed against their
own tissues, cells and their constituent parts, i.e. phenomenon of the
so called autosensibilization appears.
Theoretical and methods basics of autoallergic reactions evaluation
under environment physical factors influence for ionizing radiation were
worked out earlier by USSR AS academician R.V.Petrov and professor N.N.
Klemparskaya in 1950s-1960s in the IBPh MHP and USSR AMS academician M.G.
Shandala and professor G.I. Vinogradov in Kiev scientific-research
institute of general and communal hygiene. Later in the 1970s similar
results were received for non-ionizing radiation and for EMF
specifically.
Already first exploring researches at the beginning of the 1970s showed
that RF EMF with a power flux density ("PFD") of 50 microW/cm2 disturbs antigen brain structure that in turn leads to the appearance of sensibilized lymphocytes and autoimmune reactions..
In an experiment with the goal of tissue antigen structure study, rats
were exposed to irradiation for fourteen days under RF EMF (2450 MHz)
with a PFD of 50 microW/cm2 (Chart 1). Using the method of active anaphylaxis with desensibilization, the authors showed that antigen tissue content changed
after irradiation: in brain, liver, kidney, spleen, new antigens appear.
In this experiment they particularly studied dynamics of antibody
formation for brain tissue in RF EMF irradiated animals. Twenty-five
rats were taken for the experiment, twenty of which were irradiated with
RF EMF with a PFD of 50 microW/cm2 for fourteen days. The serum of these rats and of 5 controls was investigated in complement binding reaction (CBR)
for content of antibodies for brain tissue of normal and irradiated
rats. The reaction was given before irradiation, immediately after, and every week
after EMF influence for a month. In plate 1 (Chart 1) data on
complement binding reaction are given in rats of experimental groups
and for controls.
Complement binding reactions (CBR) in serum studies before irradiation
and in control animals were negative*. Experimental rats had antibodies
both for normal and changed in antigen brain tissue as a result of RF
EMF influence. The highest antibrain antibody titers were registered in
2-3 weeks after irradiation (titer logarithm was correspondingly 2,46 ±
2 and 2,51 ± 0,6). In four weeks the antibody titer began to decrease, and
so did the amount of positive reactions. Formation of antibodies for
healthy tissue antigens occurred similarly though the titers were much
lower.
Thus already the beginning of research showed that RF EMF with a PFD of only 50
microW/cm2 exposure could bring to changes in tissue and serum albumen
antigen structure. These changes are characterized by the appearance of a
new antigen feature that was unusual for normal albumen and with
disappearance of some normal antigens, i.e. tissue antigen structure
change occurred. But this conclusion demanded its confirmation and
development. In this connection several experiments in more complex
modifications were carried out later.
An experiment was carried out with the aim to find anti-tissue
circulating antibodies in animals irradiated by EMF for a longer time
(30 days) using complement binding reaction CBR (Chart 2). As an antigen
for the considered reaction the authors took 20% water-saline extract
(dilution 1:15) of brain tissue of healthy animals and animals that were
exposed with RF EMF for 30 days, 7 hours a day with a PFD 50 microW/cm2.
In order to get antigen from irradiated brain tissue donor-animal brain
was used that were in the same conditions as the experimental animals.
Donors were killed immediately after cessation of irradiation. The experiments
were given in three kinds of animals: rats, guinea pigs and rabbits.
Blood for complement binding reaction (CBR) was taken before and immediately
after irradiation ceased and then in 2,4,6 and 8 weeks. The results
of this experiment in guinea pigs and rats are represented in plate 2.1
(Chart 2). The investigators noticed that irradiation of animals
(guinea-pigs and rats) by RF EMF with PFD 50 microW/cm2 leads to
violation of brain cell albumen structures and the development of
circulating anti-brain antibodies.
There were certain dynamics of this process suggesting from our point of
view a possible accumulation of the noticed effects in time after
irradiation. Guinea-pig antibody titer increased greatly after
irradiation ceased, and reached its maximum two weeks afterwards
(titer logarithm was 2,77 ± 0,04).
*A positive reaction was complement-binding reaction CBR if the antibody
titer was higher than 1:20; (in control group this value was not
determined).
Similar direction of complement binding reaction (CBR) changes was when
using healthy guinea-pig brain tissue as an antigen. But the antibody
titer height was lower and antibodies were found in fewer experimental
animals. Control guinea pigs had negative complement binding reactions
(CBR). Similar changes were found in rats (see plate 2.1, chart 2).
Though rabbits were exposed to radiation only for 10 days, the same CBR
changes dynamics was received as in guinea pigs and rats.
Thus experiments on guinea pigs, rats and rabbits showed statistically
reliably that antibodies for brain tissue appear in animals as a result
of chronic RF EMF exposure with a PFD of 50 microW/cm2. This process was
noticed also when using brain tissue of both irradiated and
non-irradiated animals as antigens. The highest complement-binding
antibody titers were on 10-14 days after irradiation.
The data of the next experiment show sufficient durability of this
process (Chart 3). Using the Yerne method in N. Kleparskaya's modification,
cellular autoimmune reaction was studied by determining the amount of
plaque-forming cells, synthesizing antibodies for their own red
corpuscles in blood. The experiment was carried out on guinea pigs and
white rats exposed to radiation for a month with a PFD 50
microW/cm2. The Yerne reaction was conducted before irradiation, immediately afterwards and then in 2 and 4 weeks. The study results are given in plate 3.1
(Chart 3).
The resulting data show that a statistically important increase of
plaque-forming cells took place on the 2nd week after irradiation and
was rather stable. Four weeks after EMF exposure the rate of these
cells was still high.
Attention should be paid to correlation in content of cells producing
antibodies for red corpuscles in blood and in increased circulating
antibody titer shown in the previous experiment (plate 2.1 Chart 2) with
maximum changes in 2 weeks after irradiation.
Later the following experiment was carried out with the task of studying
damaging features of blood serum under RF EMF exposure on the basis of
changing in cell ability for phagocytosis (Chart 4).
Fifteen guinea pigs were taken for the experiment that were exposed
to RF EMF for a month with a PFD of 50 microW/cm2. The phagocytosis reaction was evaluated three times: before irradiation, in 2 and 4 weeks after its
end. Results of the phagocytosis reaction in the after-effect period
(after irradiation had ceased) are given in plate 4.1 (Chart 4). These
data show that the serum of the EMF-irradiated animal
induces a clear depressive effect both on phagocytosis value and on the
phagocytosis index mark. This influence was especially expressed in 2
weeks after irradiation and remained for 2 weeks.
Summarizing these three experiments we can make conclusions about
the autoallergic character of the process under study in animals exposed to
low intensity RF EMF with a PFD 50 microW/cm2.
Later in repeated experiment (Chart 5) rats were exposed to EMF for 7
hours daily for 30 days with a PFD of 50 and 500 microW/cm2. At the end of
irradiation the basophil degranulation degree in blood serum,
the plaque-forming cell rate and the complement-binding antibody level were
evaluated. In combination these reactions provided an autoimmune process activity
indicator as they showed forming of complement-binding antibodies for
tissue antigen and forming of autoimmune hemolysis plaques.
25% water-saline extract of brain tissue of donor-animals irradiated
with a PFD of 500 microW/cm2 for 30 days. This experiment results are given in
plate 5.1 (Chart 5).
Analysis of results represented in plate 5.1 indicates that low
intensity EMF 500 and even 50 microW/cm2 for 30 days and 7 hours daily
facilitated the forming of anti-brain complement-binding autoantibodies levels
reliably higher than in controls.
Even sharper differences from controls were seen in basophil degranulation indices
with irradiation with PFD 50 and 500 microW/cm2, and in plaque-forming cell
quantities increased 5,5 and 10 times (p<0,001).
Brain, spleen, marrow and peripheral blood morphological research was
also carried out under the same conditions of animal RF EMF irradiation.
Spleen and marrow morphological research data after EMF irradiation with
500 microW/cm2 are represented in plate 6.1 (Chart 6). Attention is paid
to the processes of differentiation and reproducing of
reticuloendotelium, blasts, lymphocytes and plasmatic cells.
As the data in plate 6.1 show, after animal irradiation with PFD 500
microW/cm2 the reticuloendothelium cell quantity in marrow increased 2,2 times and
in spleen about 2 times. Plasmatic cell quantity in marrow and in spleen
increased 4 times and small lymphocytes decreased in marrow (by/to?) for 40%. In
the group of animals exposed to EMF with a PFD of 50 microW/cm2 only an increase of reticuloendothelium cell quantity in spleen was noticed, which may
indicate some increase in reticuloendothelium system activity.
In the next experiment the model is reproduced that allows to demonstrate that
low intensity EMF are able to induce autoimmune reactions (Chart 7). In
this experiment irradiated donor brain extract was inserted into healthy
animals. For immunization 25% water-saline resolution of brain tissue
extract of donor-animals exposed to microwaves with a PFD of 50 and 500
microW/cm2 for 30 days that contained 0/9 g/l albumen. Immunization scheme
provided six-fold intraperitoneal brain tissue insertion every 24 hours.
In 2-3 weeks after immunization remaining animals were studied for extent of
basophil degranulation, plaque-forming cell content and
complement-binding antibody rate. This experiment results are given in
plate 7.1 (Chart 7). It is shown that in the group of animals immunized
with brain tissue of irradiated rats with a PFD of 500 microW/cm2 all
indicators differ statistically from controls, being
2 ½ - 8-fold higher, indicating an autoimmune reaction development in
experimental animals. Intact rats' immunization with brain tissue of
donor-animals exposed to EMF with a PFD 50 microW/cm2 didn't produce
development of firm autoimmune pathology. Significant changes were
noticed only in 2 weeks in basophil degranulation degree indicator (see
data in plate 7.1).
Thus insertion of brain tissue of rats exposed to microwaves with a PFD
of 500 microW/cm2 to intact animals induces in them autoimmune reactions. 50
microW/cm2 exposure induces less expressed immune reaction.
As we mentioned before, according to the literature the evidence of
autoimmune nature of this or that status induced by an exogenous factor
is transfer of this status into another organism with the help of
lymphoid cells (Vitebsky E. Immunology and immunopathology modern
problems. M. Medicina 1970, pp. 129-137).
Essence of adaptive immunity phenomenon is that immunologically active
tissue continues to function immunologically being transferred into
another host. According to F.Bernet's theory "excluded" cell clones
exercise immunology aggression against normal tissues (F.Bernet.
Cellular Immunology. M.: Mir,543 p.). And haematogenous tissue in
contrast with other tissue under replanting stimulates immune response
of recipient remaining inert and immune-competent cells are able
themselves to respond to recipient (Petrov R.V. Immunology and
immunogenetics. _.: Medicine, 1976 336p.).
Based on these ideas the following experiment was carried out
(Chart 8). Experiments were conducted on male Fisher rats. On the first
stage preparation of the donor-animals was exercised (12 rats) that were
exposed to RF EMF radiation with a PFD of 500 microW/cm2 for 15 days, 7 hours
daily. The same number of animals was in the control group ("false"
irradiation). After irradiation ceased immunological indicators of
the animals were studied, then they were killed, brain was extracted for
histological studies and the lymphatic glands were extracted for preparation
of lymphoid cell soliquid.
On the second stage lymphoid cells amounting to 5 x 106 /ml were inserted
intraperitoneally into 12 animal recipient from irradiated rats
(experiment) and into 12 rats from "false-irradiated" animals (control).
In 6 days after soliquid insertion brain immunological research was
carried out.
The following indicators (A) of donors' and recipients' humoral
immunity were studied:
- basophil degranulation level;
- plaque-forming cell quantity;
- complement-binding antibody rate in complement consumption
reaction (25% water-saline extract of non-irradiated animal brain
tissue was used as the antigen). Among cellular immunity indicators (B)
lymphocyte blast transformation reaction was also studied.
The results of irradiation of donor-animals by RF EMF with a PFD of 500
microW/cm2 for 15 days were the following: antibodies for brain tissue
appeared, basophil degranulation degree increased substantially, the plaque-forming
cell quantity increased 4-5 times in peripheral blood, two-fold
oppression of both spontaneous blast-forming and one modified by
different mitogens (phytohemagglytinin (FGA) and concanavalin-A (CON-A)
occurred. These data are given in plate 8.1 (chart 8).
In brain histological study nidal soft brain sheath loosening, its
moderate plethora, nucleus ectopy and their irregular form in some
sensomotor bark neurocytes and cerebellum ganglionic layer cells were
noticed. Most animals had microglia proliferation and some vascular
reactions.
In this repeated experiment same results were received as in monthly
irradiation that I represented before, i.e. previous research results
were confirmed on possible stimulation of autoimmune processes in animal
organisms exposed to RF EMF with PFD 500 microW/cm2 against cellular
immunity oppression.
Thus the represented results in experiments with insertion of
immunecompetent cells from animals exposed to irradiation with PFD 500
microW/cm2 for 15 days to recipients (plate 8.1 chart 8) indicate the
development of autoimmune reactions and antibody formation against
normal brain tissue in them. Basophile degranulation level
increased significantly, plaque-forming cell and complement-binding antibody
quantity rose, and the lymphocyte blast-forming process was depressed. In
a histological study of experimental animal-recipient brain insignificant
changes were noticed in different brain structures.
Immune deficiency in lymphocyte thymus-dependant cell population
(cellular immunity status) plays an important role in
autosensibilization. In experiment with rats under their long
irradiation with EMF 2375 MHz for a month, 7 hours daily with a PFD of 50 and
500 microW/cm2 significant depression occurred of rat peripheral blood
T-lymphocyte blast-transformation that was more clearly expressed in a higher PFD
level (plate 9.1. Chart 9). Under 500 microW/cm2 functional recovery
didn't take place even after 3 months of subsequent observation.
EMF influence on pregnancy development, foetus and posterity
It is known that natural tolerance during the fetal development antenatal period
forms only against its own antigens accessible for immunecompetent
cells. In antigens of organs that are isolated during
embryogenesis and not available for immune system, there is no
immunological tolerance.
In case of appearing of such antigens in circulation of grown-up
organisms immune reaction with antitissue antigen and sensibilized
autoaggressive lymphocyte accumulation develops. Such "over-barrier"
organs and systems include also the brain. Antigens contained in the brain are
able to induce immune reactions when inserted into the blood of their own
organism, as they are alien to their own immune system.
In the experiment on Wistar rats' low intensity RF EMF influence (500
microW/cm2) was researched for its possible development of autoimmune reactions
in pregnant female rats (Chart 10). It was received that non-irradiated
animal pregnancy development fails to induce significant appearance of
antibodies in blood. Percentage of plaque-forming cells was 1,1±0,2, at
the same time their content in peripheral blood of irradiated females
increased by the pregnancy end in 6,5 times and reached 7,3 ±1,5 %
(plate 10.1, Chart 10).
Peripheral blood basophil indirect degranulation reaction data also
point to pregnant rat autosensibilization development. It was shown
that when using fetal liver as antigen, basophil degranulation levels increase in pregnant rats exposed to EMF irradiation (experiment
56,7±2,6 %, control 12,9 ±1,9 %).
Pregnant female irradiation brings also to non-specific depression of
immunogenesis apparatus as a whole that can be seen in almost two-times
decrease of immunecompetent cell ability to stimulation under influence
of lymphocyte FGA blasttransformation (see plate 10.1).
Thus EMF influence with PFD 500 microW/cm2 during the whole rat pregnancy
period led to depression of non-specific immunogenesis, antibody
formation increase against foetus tissues and also led to autoimmune
reaction stimulation in pregnant females.
Experiments were carried out on evaluation of possible influence on
fetal development and posterity status of autoimmune processes in
pregnant female organism under RF EMF effect (Chart 11). Donor-rats were
exposed to EMF (2375 MHz) for 30 days, 7 hours daily, with a PFD of 500
microW/cm2. After determination of antiliver antibodies in serum it was
intraperitoneally inserted into rats on the 10th day of pregnancy. The
resulting data are summarized in plate 11. Thus amount decreased, posterity
number decreased, as well as the number of females with amblosis. Embryo
mortality was significant (28 %) but not seen in controls. Significantly
higher posterity mortality was noticed for the end of the 1st month of
life (30,7 % compared to 17,1 % in controls).
Thus EMF irradiation with a PFD of 500 microW/cm2 leads to appearance of
circulating autoantibodies directed against fetal tissue, i.e. mother
and foetus immunology conflict develops, giving rise to
clearly unfavorable effects in posterity.
In some other works cellular immunity of posterity from parents
irradiated by RF EMF with a PFD in the range of 10-500 microW/cm2 was
studied (Chart 12). The results of these studies indicated that both
foetus and posterity had blastformation process depression for the next
4 months. Non-irradiated females' foetus (in control) blast-forming
lymphocyte percentage was 24 ±1,4, and under exposure conditions with a PFD 500 microW/cm2 it decreased fourfold, indicating significant depression of
their blastformation process (plate 12.1).
Data on lymphocyte blast transformation quantity in young rats of
different ages (1-4 months) under different ranges of low intensity EMF
effect (PFD 10, 50 and 500 microW/cm2) on pregnant females are given in
plate 12.2. These data show distinctly that posterity of females irradiated with a PFD 500 microW/cm2 in all study times for 4 months had
peripheral blood lymphocyte blast transformation process depression. The
authors noticed also cellular differentiation violations in posterity of
white rats irradiated by EMF with PFD of 500 microW/cm2.
Thus the presented data from a small part of these experiments bring us
to the single conclusion that longterm RF EMF exposure effects (2375-2450 MHz) on experimental animals in the range of PFD 50-500 microW/cm2 (when the role
of the so called thermal effect is absolutely insignificant) gives rise to the
appearance of distinctly stable bioeffects.
On the basis of results of experimental studies for the latest 30 years
and the received distinct repeated true results under RF EMF chronic
influence standardization strategy in the USSR and later in Russia in
this frequency range was and still is built on the following principles:
1. Acute one-time RF EMF irradiation bioeffects are taken into account
in the nearest period with different PFD values (thermal and
non-thermal mechanisms).
2. Chronic low intensity EMF exposure results with experimental animals
are considered, as are results of clinical-physiological
observations and hygienic studies in controlled conditions.
3. Influencing factor rate is admittedly unfavourable if there is
reliable deviation of any vitally important organism function that
leaves the limits of physiological swings of this function and is
firmly maintained for the period of chronic influence and after its cessation.
4. Reduction of adaptational capability of the organism and its
regulations, as shown by functional physiological and
extreme loads is considered as dangerous.
5. A proportion of the minimum electromagnetic field rate able to
induce any reaction exceeding normal adaptive response of the
organism in certain EMF influence conditions is taken as being the permitted exposure limit for the general population. This influence should not cause even
temporary homeostasis violation (including reproduction function) and
protective and adaptation-compensatory mechanism tension either in
the nearest or in the remote time period.
Precisely from those viewpoints the results represented already by
myself and those that will be represented by doctors L.Tomashevskaya,
V.Nikitina and N.Rubtsova were evaluated by the specialists in the USSR
(Russia).
There is one more aspect of this problem. Whether we can use SAR concept
for such low PFD (100-500 microW/cm2) that still has been actively
incorporated in working out of standards and hazard evaluation? And if
we also take into consideration the great role of EMF modulation in
bioeffects developing and strengthening it becomes clear why the issue
of this concept revision is so often raised in some European countries
and in the USA. (W. Ross Adey, 1999). From Paper by W. Ross Adey (Review
of Radio Science, 1996-1999. Oxford Univ.Press,1999, pp 845-872):
"Observation of these modulation frequency - dependent bioeffects would appear to raise significant questions concerning the validity of continued use of thermally based Specific Absorbtion Rate (SAR) as a universally
valid predictor of bioeffects atributable to RF field exposure. It is
clearly a blanket measure blind to specifics of field characteristics
that may be critical determinants of the biological response in many
athermal exposures".
Thank you very much for your attention!
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