Cell Phones Increase the Risk of Two Types of Brain Tumor According to Study

*Cancer Monthly*
*

Using mobile phones for more than 10 years gives a consistent pattern of
increased risk for at least two different types of brain tumors. This
was the conclusion of a summary that reviewed sixteen other research
studies from seven countries – USA, Finland, Sweden, Denmark, United
Kingdom, Germany, and Japan.(1)

Cell Phones Are Like Radios

Cell phones are more like radios than traditional telephones in your
home. They emit low levels of radiofrequency energy (RF) in the
microwave range while being used. They also emit very low levels of RF
when in the stand-by mode. Using a cell phone can place the radiation
antenna close to the user’s brain and this can lead to the absorption of
comparatively large amounts of electromagnetic energy.

There has been an on-going debate about the safety of cell phones for
many years. While, not surprisingly, the cell phone industry and various
health authorities have assured users that the technology is safe,
recent research has suggested otherwise.

Researchers at the Department of Oncology, University Hospital in Sweden
reviewed sixteen published studies that looked at cell phone use and the
rate of brain cancers. They concluded that:

“For both acoustic neuroma and glioma (two types of brain cancer),
overall risk was increased in the whole group, but significantly
increased for ipsilateral exposure (tumor on the same side of the brain
as cell phone exposure)…These results are certainly of biological
relevance, as the highest risk was found for tumors in the most exposed
area of the brain, using a latency period that is relevant in
carcinogenesis.”

Increased Risk of Acoustic Neuromas

Acoustic neuromas, also called schwannomas, are a non-cancerous tumor
that develops on the nerve that connects the ear to the brain. The tumor
usually grows slowly. As it grows, it presses against the nerves
responsible for hearing and balance. Radiosurgery is usually the
standard treatment.

Signs and symptoms of acoustic neuromas may include hearing loss,
usually gradual — although in some cases sudden — and occurring on only
one side or more pronounced on one side, ringing (tinnitus) in the
affected ear, dizziness (vertigo), loss of balance, facial numbness and
tingling. The tumor also may press on the brainstem and in rare cases,
it may grow large enough to compress the brainstem and be life-threatening.

After reviewing the previous studies that looked at cell phone usage and
neuromas, the authors found “an association with acoustic neuroma…in
four studies in the group with at least 10 years use of a mobile phone.”

Their discussion of this issue included the following observations:

• Acoustic neuroma might be a “signal” tumor type for increased brain
tumor risk from microwave exposure, as it is located in an anatomical
area that receives high exposure during calls with cellular or cordless
phones.

• Three studies did not have follow-up of at least 10 years, but two of
them showed a somewhat increased risk for shorter latency periods.

• Three of the four studies with data on over ten years use showed a
statistically significantly increased risk overall or for ipsilateral
exposure to microwaves. (In this context, ipsilateral exposure means the
tumor is on the same side of the brain as cell phone exposure).

• In one study, no association was found but the result was based on
only two cases.

• The tumors were significantly larger among mobile phone users.

Increased Risk of Gliomas

The researchers also found that the risk of glioma increased
significantly per year of use.

A glioma is a type of primary central nervous system (CNS) tumor that
arises from glial cells. The most common site of involvement is the
brain, but they can also affect the spinal cord or any other part of the
CNS, such as the optic nerves. Gliomas can be either benign (slow
growing) or malignant (fast growing). Types of gliomas include:

• astrocytomas
• ependymomas
• oligodendrogliomas
• mixed gliomas

Treatment for a glioma — and survival odds — depends on tumor type, size
and location, and the patient’s age and overall health. Often, treatment
is a combined approach, using surgery, radiation therapy, and
chemotherapy. High grade gliomas like anaplastic astrocytomas and
glioblastoma multiforme can be particularly difficult to treat.

Symptoms of gliomas depend on which part of the central nervous system
is affected. A brain glioma can cause headaches, nausea and vomiting,
seizures, and cranial nerve disorders as a result of increased
intracranial pressure. A glioma of the optic nerve can cause visual
loss. Spinal cord gliomas can cause pain, weakness or numbness in the
extremities.

In respect to gliomas and cell phones, the researchers concluded “that
using a ten year or more latency period gives a consistent pattern of
association between use of mobile phones and malignant brain tumors,
especially high-grade glioma.” The researchers also found an increased
overall risk more pronounced for ipsilateral use of the cell phone
(tumor on the same side of the brain as cell phone exposure).

What to Do?

This study did not say that cell phone use leads to brain tumors, only
that long-term use may increase one’s statistical risk of certain brain
tumors. In addition, it should be noted, that other studies have
concluded that there is no connection between cell phones and increased
risk of cancer. This issue is far from resolved. But for those heavy
cell-phone users who want to err on the side of caution, it may be wise
to use one of the various non-RF devices (such as headphones) that can
place some distance between a cell phone and the user’s brain.

Endnotes

(1) Hardell L, et al., Long-term use of cellular phones and brain
tumors: increased risk associated with use for > or =10 years. Occup
Environ Med. 2007 Sep;64(9):626-32.