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					Washington, DC                                July 12, 1999

On the Need for Biologically Based Standards for Cell Phone Technology

       Martin Blank, PhD
       Associate Professor of Physiology and Cellular Biophysics
       Columbia University, New York

         There is a substantial and growing body of experimental evidence that electromagnetic
(EM) fields interact with cells and induce significant biological changes, such as altered levels of
mRNA and proteins, and increased enzyme activity. We have shown that exposure of cells to
environmental level EM fields induces stress genes and stress proteins. The cellular stress
response is a protective mechanism that enables animal, plant and bacterial cells to survive a
variety of environmental stresses, such as high temperature, toxic heavy metals and oxidative
stress. Induction of the stress response by EM fields shows that cells react to EM fields as a
potentially harmful stress.

        The widespread use of cellular phones and associated transmission towers has raised
concern regarding the potential risk of exposing people to the EM signals. Current safety
standards are based on temperature increases that accompany exposure to radio-frequency waves
used in cellular phones. But cell phones use a range of frequencies, including low frequency and
radio-frequency, and there are remarkable similarities in the biological responses to the low
frequency fields and modulated radio-frequency fields.

       It is hard to explain why safety standards for cell phone technology are based on heating
biological cells by radio-frequency EM fields, while the protective stress response is evoked by
very much lower EM field energies. We have shown that the energy threshold for stress proteins
induced by low frequency EM fields is (14 orders of magnitude) lower than the threshold for
thermal stress. To provide a basis for realistic exposure standards, it is essential to determine
whether the stress response evoked by cellular phones is EM or thermal in origin. The thermal
standard is inappropriate if the protective stress response is evoked in cells by much lower
exposures to EM fields.

References:
M Blank (1995)
       Editor and author of four chapters in "Electromagnetic Fields: Biological Interactions
       and Mechanisms", Advances in Chemistry, Vol. 250, American Chemical Society Press,
       512pp.
M Blank and R Goodman (1997) Do Electromagnetic Fields Interact Directly With DNA?
       Bioelectromagnetics 18:111-115.
R Goodman and M Blank (1998) A Non-thermal Low-energy Agent that Induces Stress
       Response Proteins: Magnetic Fields. Cell Stress and Chaperones 3:79-88.

				
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