Andrew Ireland
The danger posed by electromagnetic radiation from cell phones: a literature review.
Introduction:
Because cell phone use has skyrocketed in the 21st century, health problems caused by cell
phone use are a source of major concern. Also, the fact that over 90 percent of Americans own cell
phones means that a large population would be at risk if it were determined that they are detrimental
to human health (Khurana 2).
Cell phones work by sending low frequency electromagnetic radiation back and forth between
the phone and a nearby cell phone tower. Electromagnetic radiation has been hypothesized to be a
cause of tumors in humans and animals. Due to the proximity between the phone receiver and brain
tissue, many people worry that the radiation can cause heating of brain tissue and tumors. Research has
been conducted on the subject to determine whether there is a definite link between increased risk in
tumor formation and cell phone use. There is not enough evidence to support the statement that there
is a definite link between low-frequency electromagnetic radiation from cell phone use and an increase
in risk of development of brain tumors, such as glioma, meningioma, and acoustic neuroma. Gliomas are
tumors that form in glial cells (nerve cells in the brain and spinal cord). Meningiomas are among the
most common brain tumors and are typically benign, but sometimes malignant. Acoustic neuromas are
benign but space-occupying tumors on the auditory nerve.
Methods:
ScienceDirect was used to search for reputable sources that were written in the years between
2000 and 2011. The keywords “cell phones”, “tumors”, “radiation” and “cancer” were used. Several
papers were excluded from my research because they were outdated (published before the year 2000)
to still be considered accurate considering the exponential expansion of cell phone use since that time.
Results:
Many studies have been done on the effect of radiofrequency radiation on rats because they are
genetically and physiologically very similar to humans (Pollick 1). Thus studies done on the effects of cell
phone radiation on rats have implications on humans.
B.C. Zook conducted a study to test whether radiofrequency electromagnetic radiation
shortened the latency (time delay until onset) of brain tumors in rats that had been born with the
mutagen ethylnitrosourea (ENU). The study used rats born to a mother who had been intravenously
injected with ENU and exposed group 1 to 860MHz radiofrequency while groups 2 and 3 were exposed
to no radiofrequency. Group 1 showed no increase in incidence or latency of brain tumors when
compared to groups 2 and 3. This study disproves any link between tumor formation and mobile phone
use (Zook 1-3).
Brain tumor incidence among serially sacrificed rats exposed to 10.0 mg/kg ENU; rats irradiated with a
PRF are compared to sham and cage control rats
Age at
sacrifice
(days)
172
Exposure Groups
PRF (%)
67
Sham (%) 57
Cage (%) 73
202
232
262
292
63
57
40
73
77
58
58
78
80
57
33
60
The above table (Zook 2) illustrates the percentage of rats that were found to have brain tumors at
certain times of sacrifice. The table shows no significant differences in tumor formation at any date of
sacrifice between rats that had been exposed to PRF (pulsed radiofrequency radiation) and rats that had
been held in control (sham and cage groups)
Adamantia F. Fragopoulou conducted a study in which he exposed pregnant mice to
electromagnetic radiation from a commercially available cell phone and compared the health of the
offspring to a control group that was exposed to no radiation. The newborn offspring were sacrificed
and examined. Newborns that had been exposed to radiation showed the same phenotype as control
group mice. There was no increase in tumor occurrence for the mice that had been exposed to radiation
compared to the control groups. Newborns exposed to radiation also showed small effects in the
ossification of bones. The effects ranged from harmless to beneficial. It can be inferred from the results
of this study that the mice exposed to electromagnetic radiation had no increase in risk of tumor
formation but that the electromagnetic radiation had some effect on the development of their bones
(Fragopoulou).
Through review of the Fragapoulou and Zook studies, we can determine that cell phone use had
no effect on brain tumor incidence or latency in rats and mice. The Fragopoulou study found that cell
phone use could have some effect on the development and ossification of bones, but more studies
would need to be done on the topic to determine what link, if any, exists between the radiation and
bone ossification. Because of the similarity between mice/rats and humans, the results of these studies
can be applied to humans.
The three most often mentioned tumors in literature concerning cell phone dangers are glioma,
meningioma, and acoustic neuroma. Khurana reports that “The data achieve statistical significance for
glioma and acoustic neuroma but not for meningioma” (Khurana 1). Vini G. Khurana’s study yielded that
over ten years of cell phone use, users had an increase in risk of development of gliomas and acoustic
neuromas when compared to non-users, but had no increase in risk for meningioma. Khurana’s study
was a literature review that surveyed several long-term studies on cell phone use and tumor formation.
Khurana’s study does imply some connection between cell phone use and tumor formation, but does
not put enough restraints upon the participants in the study for the results to be accepted as direct
evidence that cell phone use causes an increase in risk of tumor formation.
It has been hypothesized by some that radiation can cause damage to DNA, but non-ionizing
radiation (like radiation from cell phones) does not contain enough energy to cause direct damage to
DNA (Sage 3). “However both ELF and RF radiation induce reactive oxygen species, free radicals that
react with cellular molecules including DNA” (Sage 3). The end result is altered DNA which increases the
risk of cancer. Although the logic is sound, any effect of oxidative stress caused by cell phone radiation
that would increase the risk of cancer would be measured in the studies done by B.C. Zook and
Adamantia F Fragopoulou as an increase in tumor formation in rats/mice exposed to cell phone
radiation. Because they measured no significant difference in tumor formation, oxidative stress’ effects
on tumor formation must be insignificant.
The first graph (Khurana 2) shows the incidence of brain tumors per 100,000 people per year in the
United States as reported by the Central Brain Tumor Registry of the United States. The second graph
(Khurana 8) illustrates the percentage of the population that uses cell phones as reported by the
International Telecommunication Union. A steady increase in both incidence of brain tumors and use of
cell phones can be seen from the graphs between the years 195 and 2004, but this does not necessarily
imply a connection between brain tumor incidence and cell phone use.
Conclusions:
Because irrefutable evidence linking cell phone use to an increase in risk of brain tumors, it
cannot be stated that cell phone use leads to an increased risk for brain tumors such as meningioma,
glioma, and acoustic neuroma. Although the study done by Vini G. Khurana offered compelling evidence
that long term users of cell phones did suffer from an increased risk of brain tumor formation, the study
itself is a literature review that surveyed the results of several case studies that were all conducted with
different parameters and thus had results that were not all parallel. Because each of the case studies
had different aims, uniting the data of each study into one results section would be difficult. Thus results
of the literature review are not as compelling as the results of the case studies conducted by Zook and
Fragapoulou. Meanwhile, two other studies on the effects of radiation on mice and rats offered data
that suggested that there was no correlation at all between exposure to cell phone radiation and tumor
formation. The study conducted by B.C. Zook found no increase in tumor incidence among rats that had
been exposed to radiation analogous to cell phone radiation when compared to control groups in a well
conducted experiment. Meanwhile, the study conducted by Adamantia F. Fragapoulou found negligible
effects in the ossification of bones in developing mice but recorded no changes in tumor incidence
between mice which had been exposed to radiation compared to control group mice. Because the study
by Khurana was a comprehensive literature review of several case studies, it was not controlled
uniformly and its results are not as compelling compared to the hard numbers supplied by Zook’s and
Fragapoulou’s studies.
The result of this literature review shows that more research needs to be done on the possible
link between cell phone use and tumor incidence. Because some results showed compelling evidence
against a link, and other results showed uncompelling evidence that there was a link between tumor
formation and cell phone use, it would be prudent to conduct more long-term case studies where cellphone users and non-users are held separate over a period of ten years after which the percentage of
each group that has tumors is measured. Such studies would provide irrefutable evidence of any such
link.
The results of further research would have strong implications in the wireless technologies
industries. The large amount of Americans that use cell phones (over 90 percent) indicates a large
population that would be at risk of glioma, meningioma, and acoustic neuroma if a link between cell
phone use and cancer formation was confirmed. If such a link was confirmed, large-scale changes would
need to be made to the lifestyles of cell phone users. Personal action would likely be the most prudent
way to protect people from the dangers of radiation because it would be difficult to pass legislation that
would properly protect people from such dangers. If the link is confirmed by further research, Congress
should pass a bill that would require cell phones to have warning labels warning of the dangers of
excessive use.
References
Blackman C. 2009. Cell phone radiation: Evidence from ELF and RF studies supporting more
inclusive risk identification and assessment. Pathophysiology 16(2-3):205-16.
Fragopoulou AF, Koussoulakos SL, Margaritis LH. 2010. Cranial and postcranial skeletal
variations induced in mouse embryos by mobile phone radiation. Pathophysiology
17(3):169-77.
Khurana VG, Teo C, Kundi M, Hardell L, Carlberg M. 2009. Cell phones and brain tumors: A
review including the long-term epidemiologic data. Surg Neurol 72(3):205-14.
Why are rats used in animal testing? [Internet]; c2010 [cited 2010 November 1, 2010]. Available
from: http://www.wisegeek.com/why-are-rats-used-in-animal-testing.htm .
Sage C and Carpenter DO. 2009. Public health implications of wireless technologies.
Pathophysiology 16(2-3):233-46.
Zhao T, Zou S, Knapp PE. 2007. Exposure to cell phone radiation up-regulates apoptosis genes
in primary cultures of neurons and astrocytes. Neurosci Lett 412(1):34-8.
Zook BC and Simmens SJ. 2002. Effects of a cell phone radiofrequency (860 MHz) on the
latency of brain tumors in rats. Int Congr Ser 1236:137-9.