CONCLUSIONS

Data Gaps and Unresolved Questions. Review of the testimony reveals that scientists' knowledge of the potential hazards of low-frequency electromagnetic fields has a number of weaknesses and gaps, including:

• The experts (particularly those testifying at the hearings) disagree about whether biological effects result from low-frequency electromagnetic fields at low intensities and whether effects imply a potential hazard to humans.
• Experiments claimed to support the existence of effects are challenged, based on poor experimental design and inadequate statistical treatment of results.
• Experimental evidence for biological effects creating a hazard for man is, at best, dubious. Some of the results presented by Marino indicate that the fields may produce a stress response of the type described by Hans Selye. However, stress response is a difficult concept to define, and experimental studies on stress response require extraordinary care in experimental design and execution. Past experiments referred to in the hearings lack such care. Current and future experiments may be more revealing.
• The hearings offer little evidence that people are adversely affected at home or at work by electric fields at power line frequencies. This absence of evidence cannot be assumed to indicate that there are no adverse effects; however, it does imply that if effects occur, they are more subtle than common occupational diseases (e.., silicosis) or diseases resulting from widespread environmental pollutants such as urban smog.
• With minor exceptions, the testimony revealed no systematic study of thresholds of intensity or duration of exposure required to produce alleged biological effects. In the absence of such studies, it is impossible to set meaningful permissible levels of exposure.

Research Credibility. The New York State Public Service Commission hearings strongly indicate that at issue is the credibility of interpretations of the results of biological research previously conducted and currently under way. However, the issues primarily arise from the adversary circumstances that prompted the hearing, and do not necessarily reflect adversely on the scientific studies that have been performed. Nevertheless, the scientific evidence presented before the Commission involved problems that are not widely recognized outside the scientific community.

First, by comparison with the multitude of chemical and physical environmental agents, both man-made and natural, the fields of UHV power transmission lines appear remarkably benign. Well-conceived carefully planned, meticulously executed experiments are required to detect evidence of their effects (if any) in living organisms. If alterations are observed in the parameters of the biological system under study, the question of the cause-and-effect relationship between the imposed electromagnetic fields and the alterations must be carefully considered to ascertain whether or not some other uncontrolled variable of the experiment rather than the fields may have, in fact, caused the alteration. Unfortunately, as the hearings pointed out, most research conducted in this area can be criticized at all levels-from conception and execution through conclusions that failed to account for artifacts due to uncontrolled variables.

Second, the research literature is unevenly "weighted." Scientists do not like negative (perhaps more correctly "non positive") results. In the existing "publish-or perish" milieu of academic research, positive findings le.g., an effect resulting from UHV field exposure) result in more publications, professional recognition, public visibility, and general acclaim than do negative ones. The research literature is therefore replete with "positive" results but is lacking in "negative" results. As a result, the lay reader is given the impression that effects occur, which even the simplest scientific experiment will display.

Finally, much of the evidence presented before the Commission came from scientific studies that were unrelated to determining human hazard. Those that were oriented toward human hazard came largely from the Project Sanguine investigation, whose primary concern was magnetic fields, and whose electric fields were small in comparison with those associated with power lines. Given the generally innocuous biological effects of the electric fields, the absence of systematic prior investigation of hazard, and competing viewpoints at the hearing, it is not surprising that the scientific knowledge available for consideration was not definitive.

DOE Research Activities

DOE, the Electric Power Research Institute, and others have research programs underway to examine biological effects, if any, of transmission line electromagnetic fields. DOE programs include:

· Basic biological studies

- Possible mutagenic effects of dc and 60-z fields. Battelle Pacific Northwest

Laboratories is studying Drosophila (the fruit fly) and microorganisms exposed

to extremely high field strengths much higher than those under transmission

lines). If effects are found, Battelle will attempt to measure a relationship between field strength and effect, and to delineate the mechanism that relates

observed effects to field strength.

- Possible genetic changes or perturbations in cell replication rate or survival

rate in mammalian cells exposed to 60-Hz electric fields in vitro in a conducting medium). Sandia Laboratories in Albuquerque and the Los Alamos Scientific Laboratory are undertaking these studies, and will also investigate effects on chromosome structure.

-Possible effects of 60-Hz electromagnetic fields on the central nervous system. The Jerry L. Pettis Memorial Veterans Hospital, Loma Linda, California, is attempting to determine the mechanisms underlying the interaction of electromagnetic fields with living tissue.

· Applied studies

-Possible animal responses to 60-Hz electromagnetic fields. Battelle Pacific Northwest Laboratories is examining the response of rats and mice to electromagnetic fields. A broad range of biological factors is being observed, including growth, reproduction, and development of offspring, as well as body weights, weights of endocrine organs, levels of various plasma components, cardiovascular function, and effects on the central nervous system.

-Feasibility of using nonhuman primates to study the effects of 60-Hz electromagnetic fields. Southwest Research Institute is establishing experimental protocols for determining the effects of high-intensity fields on biological factors and behavior. Once established, these protocols will be used in conducting a long-term study on primates and with the objective of relating

those results to humans.

-Possible effects of 60-Hz electromagnetic fields on circadian rhythms. Argonne National Laboratory is measuring circadian regulatory mechanisms in mammals under controlled exposures to uniform fields.

-Feasibility of using a battery of assay tests (which have been used to test

central nervous system functions at microwave frequencies) to determine

whether 60-Hz electric fields affect the central nervous system. Randomline,

Inc., of Philadelphia, is undertaking this work.

-Perception of and aversion to 60-Hz electric fields. The University of Roches-

ter is determining thresholds for perception of, and aversion to, 60-Hz electric

fields in rats.

· Ecosystem studies

-Possible effects of 1200-kV transmission line operation on natural vegetation,

crops, wildlife, cattle, and honey bees. These studies started immediately after

the Bonneville Power Administration test line at Lyons, Oregon, began opera-

tion.

-Observation of bird nests on transmission lines. Bonneville Power Administra-

tion is undertaking these obsenations to determine the number and types of

birds nesting on EHV transmission lines. Nesting platforms have been con-

structed on towers to facilitate observation.

Note that these experiments cannot fully resolve the question of whether or not transmission lines are hazardous. Certainly, they will help elucidate the problem and possibly allay some concern about possible hazards. Current uncertainties associated with defining the biological effects of transmission line fields (as well as fields of different strengths and frequencies) make it difficult to formulate research programs aimed at hazard assessment. Furthermore, the results of research already under way may determine that the fields are not hazardous. Studies of threshold intensities, dependence of effect on intensity, and variability of response in humans will be valuable in attempting to assess hazard.

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