7. The scientific controversy
Scientists are working to explain how low-level non-ionizing EMFs could have convincing and replicable effects on living systems, as they do not carry enough energy, either to damage
biomolecules, or to cause heating effects. The existence of non-thermal effects of low-level, low-frequency EMFs in biological matter remains a theoretical mystery, but an experimental and clinical fact. Therefore, an explanation of the facts happening in the laboratories of experimental scientists, requires a new paradigm for the scientific perception of life processes.
The debate has so far been dominated by physical concepts and arguments. The theoretical "signal-to-noise" dilemma is among the most persistent of the criticisms which have cast doubt on the credibility of reports that weak ELF fields have been shown to affect life processes in biological systems. Exogenous ELF fields reported to induce biological effects have been shown to be orders of magnitude weaker than the endogenous fields associated with "thermal noise" – the randomly fluctuating local fields on the surface of the cell membranes, caused by random thermic movements of charges (ions) in the inter- and intracellular liquids.
In other words, according to this theoretical argument, the induced electrical field of an exogenous ELF should be "drowned" by the thermal noise field inside the tissue. This belief is drawn from the solutions to fundamental mathematical equations from electromagnetic theory, according to which tissue is modeled as an ensemble of simple, smooth, non-interacting insulators surrounded by a conducting medium. These simplified equations result in an induced electrical field which has an order of magnitude equal to the exogenous field.
The simplified theory neglects the electromagnetic detail of the biological cell, which is a complex structure, rich with convoluted, charged surfaces. At the Catholic University of America
(CUA) in Washington, D.C., Dr. Joan Farrell has made calculations taking into account a more realistic representation of the electromagnetic properties of the biological cell. The result of this more accurate mathematical model lead to the discovery that exogenous ELF fields induce an electric field in tissue which may become amplified by orders of magnitude relative to the exogenous field. It allows for calculation of the fields close to the cell’s surface, where the cell’s array of "detectors" or chemoreceptors operate.
There are other frameworks for understanding the phenomenon of ELF field induced biological effects, and one does not necessarily exclude the others. There may be several mechanisms simultaneously in play. At CUA, the team of scientists headed by Professor Litovitz have studied EMF induced effects for more than ten years. In 1993 [ref. 14], professor Litovitz and co-workers proposed that living cells discriminate against thermal noise fields by recognizing them as spatially incoherent, i.e. uncorrelated at different receptor locations on the cell membrane. The team suggested that biological cooperativity - known from other areas of biology (bacterial chemotaxis) and physiology (the functioning of the ear) - is an essential feature of cellular response to EMF; a significant number of receptors at the cell membrane must be simultaneously and coherently activated (coincidence detection) to produce an effect on the functioning of the cell. EMFs must be spatially coherent if they are to affect cell functioning. All external EMFs have the property of being spatially coherent, whereas internal thermal noise fields do not. The team has substantiated their hypothesis with comprehensive scientific studies.
The hypothesis of biological cooperativity enabling sensing of very weak exogenous fields is supported by research done on electric sensing by fish. At sea, dogfish and blue sharks have been observed to execute apparent feeding responses to dipole electric fields designed to mimic prey. Voltage gradients of only 5 nanovolts (one billionth of a volt) per centimeter would elicit the response. Thus, it is definitely possible for beings to sense exogenous fields which are even millions of times smaller than thermal noise fields.
Compared to ELF fields, it is easier to accept that RF and MW fields may cause biological effects, since these fields carry more energy, and electric fields induced in tissue by RF/MW are - without enhancement mechanisms in play – in themselves orders of magnitude higher than the thermal noise fields. Still, however, many scientists are skeptical towards the existence of non-thermal biological effects of low-level RF/MW fields, as they believe that the only effects possible are associated with heating.
Another factor adding to the skepticism towards the existence of biological effects of low-level non-ionizing EMF is the issue of replication. Some laboratories may see one level of effect of an EMF on a specific biological mechanism in a particular line of cells, tissue or animals, while other laboratories may find another level or even no effect. Scientists at the Catholic University of America have studied this phenomenon and found that it may be due largely to differences in the genetics between different strains of cells or animals. Most laboratories usually do not control this confounder when attempting to replicate the results of another laboratory.
In response to the growing body of scientific evidence, the existence of health and biological effects associated with exposures to EMFs is becoming more widely known and accepted. More and more scientists now believe that the low-level non-ionizing EMF induced non-thermal effects are a reality.
For example, on Wednesday, July 24, 1998, a 28-member panel convened by the National Institute of Environmental Health Sciences (NIEHS) decided that extremely low frequency (ELF) electromagnetic fields should be regarded as possible carcinogens.
The final vote of the panel was 19 to 9 in favor of categorizing ELF EMFs, such as those from power lines and electrical appliances, as possible carcinogens. The vote followed one year of study including three major, multi-day symposia and a final 10 day intensive meeting of scientists to review and debate the scientific and medical literature.
In October 1998 at the University of Vienna Workshop on Possible Biological and Health Effects of Radio Frequency (RF/MW) Electromagnetic Fields, (ref. 15) the following resolution was made by the participating scientists (the "Vienna Resolution"):
"The participants agreed that biological effects from low-intensity exposures are scientifically established. However, the current state of scientific consensus is inadequate to derive reliable exposure standards. The existing evidence demands an increase in the research efforts on possible health impact and on adequate exposure and dose assessment."
In conclusion, scientists working in the field of "bioelectromagnetics" are now convinced that man-made EMFs disturb biological processes (induce biological effects). Some of the biological effects seen in the laboratories are similar to biochemical mechanisms believed to be responsible for neurological effects like short term memory loss, whereas others are believed to be involved in the development of serious disorders like cancer, Alzheimer’s and Parkinson’s.
There is no definitive conclusion whether this may lead to these serious diseases, and research may not be able to provide unequivocal answers until the causes of these diseases have been identified completely. Should we know one day what role low-level non-ionizing EMFs play in cancer, it will only be because we will also know what causes cancer. Until such time, science will have no choice but to continue advancing, studying and rejecting new hypotheses until finally, from many individual findings, a conclusive overall picture of cancer and other diseases emerges.
However, until that time, the NIEHS working group has issued a public health warning. A substantial body of scientific evidence points to a relationship between EMFs and cancer.
EMF Issues • EMF FAQ • Press Articles • Scientific • Press Releases • Products • About EMF Bio • ICS Website