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resulted in two findings in particular that merit
additional study:
1. In a hospital-based, case-control study,
researchers looked for an association
between mobile phone use and either glioma
(a type of brain cancer) or acoustic neuroma
(a benign tumor of the nerve sheath). No
statistically significant association was found
between mobile phone use and acoustic
neuroma. There was also no association
between mobile phone use and gliomas
when all types of types of gliomas were
considered together. It should be noted that
the average length of mobile phone exposure
in this study was less than three years.
When 20 types of glioma were considered
separately, however, an association was
found between mobile phone use and one
rare type of glioma, neuroepithelliomatous
tumors. It is possible with multiple
comparisons of the same sample that this
association occurred by chance. Moreover,
the risk did not increase with how often the
mobile phone was used, or the length of the
calls. In fact, the risk actually decreased with
cumulative hours of mobile phone use. Most
cancer causing agents increase risk with
increased exposure. An ongoing study of
brain cancers by the National Cancer
Institute is expected to bear on the accuracy
and repeatability of these results.1
2. Researchers conducted a large battery of
laboratory tests to assess the effects 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 of the RF
except for the micronucleus assay, which
detects structural effects on the genetic
material. The cells in this assay showed