Analysis
As was seen in chapter 1, the ability of electricity to cause tissue heating and shock was well known even before the tum of the century. In the United States these became the only recognized biological effects of electricity. As a consequence, from a side-effects viewpoint, tissue heating and shock were the only hazards guarded against during the development of the electrical power and communications industries. This approach translated into the 10,000-µW rule for permissible exposure which was adopted by the military services and industry (but not by the federal government which pre-empted the right to regulate EMFs and then elected not to establish any environmental or occupational safety levels). In the Soviet Union, however, EMF regulation developed very differently. Soviet investigators reported that electromagnetic energy could affect the central nervous, cardiovascular, and endocrine systems without causing tissue heating or shock. These results led to the adoption of a 10-µW rule for the workplace and a 1-µW rule for the general environment. The Soviets also adopted regulations governing exposure to levels of power-frequency fields considered to be completely safe in the West. The evidence (part four) now shows, overwhelmingly, that the Soviet approach was the correct one. Indeed, no other outcome was possible given both the demonstrated role of intrinsic EMFs in physiological regulation (chapter 2), and the sensitivity of living organisms to natural EMFs (chapter 3).
Since one or more mechanisms of interaction facilitated EMF-induced bioeffects in a laboratory, and since the levels of EMFs studied in the laboratory are omnipresent in the environment, it must be expected that the same or similar mechanisms will facilitate an interaction between environmental EMFs and exposed subjects. It is therefore clear from the laboratory studies that, because nonthermal EMFs are capable of altering physiological functions, chronic exposure to them in the environment can result in some risk to health.
The extent of the risk is, at present, only dimly perceivable. For one thing, most laboratory studies have been relatively short-term efforts that involved exposure to the test system for days or weeks, but rarely longer. Human exposure in the environment is obviously longer-term, and the present laboratory studies can only provide an inkling of the true consequences. Another point is that the laboratory studies have usually involved only one frequency or field in contrast to environmental EMFs which consist of a superimposition of many frequencies and fields, and the possibility of a synergistic interaction in the environment is virtually unexplored.
As we have shown, the biological concept of stress affords the most useful approach to the analysis of bioeffects caused by EMFs. Applied to environmental exposure, the stress hypothesis leads to the conclusion that the disease or effect produced in exposed subjects will depend on the genetic predisposition and previous history of each subject, as well as on the electrical characteristics of the EMF and the conditions of exposure. Thus, epidemiological studies would be expected to show a correlation between environmental EMFs and a broad class of ills, rather than a specific disease, because that is the expected result in an animal population chronically subjected to any stressor. This is precisely what has been found in the epidemiological studies and surveys. Associations have been reported between environmental EMFs and diverse phenomena including cancer, suicide, and cardiovascular function. In the occupational setting, a disease syndrome has been identified in individuals exposed to EMFs that leads to a clinically diagnosable state of biological stress, and to specific effects such as cataracts and, apparently, changes in human reproduction.
What is the appropriate basis upon which to regulate environmental EMFs? Recently, the Public Service Commission of West Virginia in approving construction of a high-voltage power line with no provision for protection of the public from the electric and magnetic fields, reasoned that there were no known biological effects of such fields in people who were regularly exposed to similar fields of other lines (68). This finding, while technically correct, is hardly surprising because there have been no studies of the health consequences of such chronically exposed subjects. Under this regulatory approach-known as the dead-body theory-the regulator demands legal evidence of actual harm to exposed subjects. The absence of such evidence-for whatever reason-is construed against the interests of the exposed subjects, usually product users of local land-owners. We think that this approach is wrong because it is both unfair and unethical. EMF-producing industries, which have resources to support epidemiological studies but have failed to do so, should not be allowed to shift the onus to the consumer or local landowner who is in no position at all to supply such proof. The dead-body approach, moreover, wrongly presupposes the acceptability of using human beings in an involuntary program of damage assessment of EMF levels known to be biologically active from laboratory studies. Federally-supported investigators in the U.S. cannot lawfully and ethically apply, for example, 10 µW or 500 v/m or 0.5 gauss to human subjects in a laboratory study without first following all the rules and safeguards attendant to human experimentation protocols. It seems grossly inconsistent, therefore, for private industrial groups, and others, to do so.
Risk-evaluation is an alternative, and we suggest much superior, approach to the regulation of environmental EMFs. Here the regulatory agency focuses on the laboratory studies and tries to determine their relevance to the particular health-and-safety evaluation at hand, and the degree of risk that may permissibly be imputed to the human-exposure situation. It asks: was the strength and frequency used in the laboratory comparable to that which will be produced by the hardware under consideration? How does the duration of laboratory exposure compare to the normal patterns of human exposure that will occur? What was the test species? (Clearly results from monkeys merit more weight than those obtained from bean plants.) Was the optimum species used for the particular physiological characteristic monitored? (The pig, for example, in studies of skin-healing, or the rabbit for studies of EMF-induced cataracts.) Were there any biophysical factors -the size or shape of the test species, for example- that require consideration in relating the animal tests to human beings? Based on these and other similar factors, and with knowledge of the particular EMF levels that will occur in the environment, the agency is in a reasonable position to fix the risk aspect of its risk/benefit analysis.
The risk-evaluation approach to the regulation of nonthermal environmental EMF was followed in the 1970s, connection with its regulation of emission levels of microwave ovens. BRH set the allowable leakage levels of new ovens at 1000 µW/cm2 (69). The approach was subsequently followed in 1977 by the California Energy Commission (70), and in 1978 by the New York Public Service Commission (71); in both cases rules were drawn to protect the public from exposure to power-frequency fields from high-voltage power lines.