Appendix C
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2 Researchers conducted a large battery of laboratory tests to assess
the effect of exposure to mobile phone RF on genetic material.
These included tests for several kinds of abnormalities, including
mutations, chromosomal aberrations, DNA strand breaks, and
structural changes in the genetic material of blood cells called
lymphocytes. None of the tests showed any effect from the RF
except for the micronucleus assay, which detects structural effects
on the genetic material. The cells in this assay showed changes
after exposure to simulated cell phone radiation, but only after 24
hours of exposure. It is possible that exposing the test cells to
radiation for this long resulted in heating. Since this assay is known
to be sensitive to heating, heat alone could have caused the
abnormalities to occur. The data already in the literature on the
response of the micronucleus assay to RF are conflicting. Thus,
follow-up research is necessary.2
FDA is currently working with government, industry, and academic
groups to ensure the proper follow-up to these industry-funded
research findings. Collaboration with the Cellular
Telecommunications Industry Association (CTIA) in particular is
expected to lead to FDA providing research recommendations and
scientific oversight of new CTIA-funded research based on such
recommendations.
Two other studies of interest have been reported recently in the
literature:
1 Two groups of 18 people were exposed to simulated mobile phone
signals under laboratory conditions while they performed cognitive
function test. There were no changes in the subjects’ ability to recall
words, numbers, or pictures, or in their spatial memory, but they
were able to make choices more quickly in one visual test when they
were exposed to simulated mobile phone signals. This was the only
change noted among more than 20 variables compared.3
2 In study of 209 brain tumor cases and 425 matched controls, there
was no increased risk of brain tumors associated with mobile phone
use. When tumors did exist in certain locations, however, they were
more likely to be on the side of the head where the mobile phone
was used. Because this occurred in only a small number of cases,
the increased likelihood was too small to be statistically significant.4
In summary, we do not have enough information at this point to
assure the public that there are, or are not, any low incident
health problems associated with use of mobile phones. FDA
continues to work with all parties, including other federal agencie s
and industry, to assure that research is undertaken to provid e the
necessary answers to the outstanding questions about the safety
of mobile phones.