SAR – is it Relevant?

Evaluation of Specific Absorption Rate as a Dosimetric Quantity for Electromagnetic Fields Bioeffects,

  •  Dimitris J. Panagopoulos * E-mail: Affiliations: Department of Biology, University of Athens, Athens, Greece, Radiation and Environmental Biophysics Research Centre, Athens, Greece
  •  Olle Johansson,  Affiliation: Experimental Dermatology Unit, Department of Neuroscience, Karolinska Institute, Stockholm, Sweden
  •  George L. Carlo  Affiliation: The Science and Public Policy Institute, Institute for Healthful Adaptation, Washington, D.C., United States of America



Purpose: To evaluate SAR as a dosimetric quantity for EMF bioeffects, and identify ways for increasing the precision in EMF

dosimetry and bioactivity assessment.

Methods: We discuss the interaction of man-made electromagnetic waves with biological matter and calculate the energy transferred to a single free ion within a cell. We analyze the physics and biology of SAR and evaluate the methods of its estimation. We discuss the experimentally observed non-linearity between electromagnetic exposure and biological effect.

Results: We find that: a) The energy absorbed by living matter during exposure to environmentally accounted EMFs is normally well below the thermal level. b) All existing methods for SAR estimation, especially those based upon tissue conductivity and internal electric field, have serious deficiencies. c) The only method to estimate SAR without large error is by measuring temperature increases within biological tissue, which normally are negligible for environmental EMF intensities, and thus cannot be measured.

Conclusions: SAR actually refers to thermal effects, while the vast majority of the recorded biological effects from man-made non-ionizing environmental radiation are non-thermal. Even if SAR could be accurately estimated for a whole tissue, organ, or body, the biological/health effect is determined by tiny amounts of energy/power absorbed by specific biomolecules, which cannot be calculated. Moreover, it depends upon field parameters not taken into account in SAR calculation. Thus, SAR should not be used as the primary dosimetric quantity, but used only as a complementary measure, always reporting the estimating method and the corresponding error. Radiation/field intensity along with additional physical parameters (such as frequency, modulation etc) which can be directly and in any case more accurately measured on the surface of biological tissues, should constitute the primary measure for EMF exposures, in spite of similar uncertainty to predict the biological effect due to non-linearity.

Three Davids, one Goliath

Scientists collaborate to tell the world why microwave guidelines are inappropriate, by John Weigel

…Three of the most prominent minds in modern science have joined forces to produce a document that reformulates how electromagnetism affects living organisms and the failure – through intent or ignorance or indifference – of science, governments and big business to protect all living things…. The three eminent Scientists endeavor to bring insight into how we should be measuring microwave radiation as opposed to the way it is measured now. It is described as revolutionary as when Galileo told the people the world is round instead of flat. Currently we are measuring by SAR which is a thermal consideration and this does not cover the actual exposure of radiation effects on biological tissue/cells or the impact of the signal upon the nerves


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