LG -TM510 Operator's Manual page 33

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 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 Telecommunication
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 tests. 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 a 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)
(1) Muscat et al. Epidemiological Study of Cellular Telephone Use and Malignant Brain Tumors. In:
States of the Science Symposium;1999 June 20; Long Beach, California.
(2) Tice et al. Tests of mobile phone signals for activity in genotoxicity and other laboratory assays. In:
Annual Meeting of the Environmental Mutagen Society; March 29, 1999, Washington, D.C.; and
personal communication, unpublished results.
(3) Preece, AW, Iwi, G, Davies-Smith, A, Wesnes, k, Butler, s, Lim, E, and Varey, A. Effect of a 915-Mhz
simulated mobile phone signal on cognitive function in man. Int. J. Radiat. Biol., April 8, 1999.
(4) Hardell, L, Nasman, A, Pahlson, A, Hallquist, A and Mild, KH. Use of cellular telephones and the
risk for brain tumors: a case-control study. Int. J. Oncol., 15: 113-116, 1999
32 M510 Ver. 1.1.5