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The energy levels associated with radio frequency energy,
including both radio waves and microwaves, are not great
enough to cause ionization of atoms and molecules.
Therefore, RF energy is a type of non-ionizing radiation.
Other types of non-ionizing radiation include visible light,
infrared radiation (heat), and other forms of electromagnetic
radiation with relatively low frequencies.
While RF energy does not ionize particles, large amounts can
increase body temperatures and cause tissue damage. Two
areas of the body, the eyes and the testes, are particularly
vulnerable to RF heating because there is relatively little
blood flow in them to carry away excess heat.
Research Results to Date: Is there a connection
between RF and certain health problems?
The results of most studies conducted to date say no. In
addition, attempts to replicate and confirm the few studies
that have shown a connection have failed.
The scientific community at large therefore believes that the
weight of scientific evidence does not show an association
between exposure to Radio Frequency (RF) from cell phones
and adverse health outcomes. Still the scientific community
has supported additional research to address gaps in
knowledge. Some of these studies are described below.
Interphone Study
Interphone is a large international study designed to
determine whether cell phones increase the risk of head and
neck cancer. A report published in the International Journal
of Epidemiology (June, 2010) compared cell phone usage for
more than 5,000 people with brain tumors (glioma and
meningioma) and a similar number of healthy controls.
Results of this study did NOT show that cell phones caused
brain cancer. In this study, most people had no increased risk
of brain cancer from using cell phones. For people with the
heaviest use of cell phones (an average of more than ½ hour
per day, every day, for over 10 years) the study suggested a
slight increase in brain cancer. However, the authors
determined that biases and errors prevented any conclusions
being drawn from this data. Additional information about
Interphone can be found at
http://www.iarc.fr/en/media-centre/pr/2010/pdfs/pr200_E.pdf.
Interphone is the largest cell phone study to date, but it did
not answer all questions about cell phone safety. Additional
research is being conducted around the world, and the FDA
continues to monitor developments in this field.