6,486 Studies Reviewed. 85.2% of Original Studies Found Biological Effects. The Evidence is Clear.
Shield Your Body
Whole Body / GeneralPart of the Glaser Archive

Biological Effectiveness of Magnetic Fields

Bioeffects Seen

Authors not listed · 1971

Share:

This report's literature survey found studies on magnetic field effects often contradictory, and most reviews concluded the data are too inadequate to set permissible static field exposure levels.

Plain English Summary

Summary written for general audiences

This technical report introduces the question of the biological effectiveness of magnetic fields and surveys a literature it describes as extensive and often in apparent contradiction. Of the comprehensive reviews it lists, only Ketchen, Porter and Bolten (1978) attempted to postulate human exposure limits, recommending 0.02 T (Tesla) for continuous exposure to static magnetic fields. The remaining reviews concluded that data inadequacies do not allow informed statements regarding permissible exposure levels.

Why This Matters

This report opens by noting that the literature on the biological effects of magnetic fields has grown quickly in the last decade yet is often in apparent contradiction: some studies report influences on cellular membranes, enzyme systems and liquid crystals, while others fail to find the same results. Many studies observed subjective effects such as fatigue, irritability, and changes in appetite that are difficult to assess quantitatively, and others show a lack of concern for dosimetry and replication, so few literature references appear to meet the standards for reliable scientific reporting. The Tesla figures give the scale: the recommended 0.02 T compares with the earth's natural field of approximately 0.05 milli-Tesla, and its apparent basis is a lowest-exposure experiment, with no effect reported, at 0.008 to 0.01 T of continuous exposure.

Cite This Study
Unknown (1971). Biological Effectiveness of Magnetic Fields.
Show BibTeX
@article{biological_effectiveness_of_magnetic_fields_g7265,
  author = {Unknown},
  title = {Biological Effectiveness of Magnetic Fields},
  year = {1971},
  
  
}
No DOI on file for this study.

Quick Questions About This Study

Ketchen, Porter and Bolten (1978) recommended 0.02 T for continuous exposure to static magnetic fields. The apparent basis is that the lowest exposure experiment reviewed, for which no effect was reported, used 0.008 to 0.01 T of continuous exposure. The earth's natural field is approximately 0.05 milli-Tesla.
The literature is extensive and often in apparent contradiction. Some studies report influences on cellular membranes, enzyme systems, and liquid crystals while others fail to find the same results, and some exposures to high field strengths produced no reported change while others showed changes following exposures to low field strengths.
The surveyed studies examined cellular membranes, enzyme systems, liquid crystals and other biologically important systems, as well as growth and viability in tissue culture and animal systems.
Many studies observed subjective effects such as fatigue, irritability, and changes in appetite that are difficult to assess quantitatively. Others show a lack of concern for dosimetry, replication, or other important experimental characteristics, and few literature references appear to meet all the necessary standards for reliable scientific reporting.
Only Ketchen, Porter and Bolten (1978) attempted to postulate human exposure limits, at 0.02 T for continuous static field exposure. The remaining reviews concluded explicitly or implicitly that data inadequacies do not allow informed statements regarding permissible levels of exposure to static magnetic fields.