Introduction
In light of the colossal increase in mobile phone usage since the mid-1990s to over 5 billion users all over the globe today, a major public health issue has emerged concerning the connection between mobile phone use and its potential to cause chronic diseases such as cancer – particularly brain cancer. Since the introduction of mobile phones, there have been many epidemiologic studies on mobile phone use with particular focus on tumors of the central nervous system, in which the brain is the section most exposed to radio frequency electromagnetic fields emitted by a functional mobile phone held to the ear (Kundi 2009, p.318).
Findings of many different epidemiologic studies have only serve to heighten the controversies surrounding the appropriate interpretation and the level of bias and the level of increased and reduced risk estimates relating to mobile phone use and brain cancer. The inconclusiveness of the studies relating to this subject have been primary due to the nature of brain cancer to develop over a long period of time after exposure, conflicts of interests amongst research bodies, as well as the considerable room for improvement in the very experimental designs of the studies. In this regard, there is need for further comprehensive studies that corroborate both anecdotal and statistical evidence on the connection between mobile phone use and brain cancer so as to prove the existence of a link.
The potential cause of brain cancer as a result of mobile phone use essentially refers to the damage of brain cells due to the vibrating signals emanating from the mobile phone. The concern over the potential for mobile phones to result in brain cancer relates to three main type of brain tumors: (1) cancer of the parotid (a gland adjacent the ear); (2) glioma (a rapidly spreading type of brain tumor); and (3) acoustic neuroma (a type of tumor that usually develops on the nerve linking the ear and brain) (Kundi 2009, p.319).
The growing database notwithstanding, the concerns have not been laid to rest and the potential adverse health effects of mobile usage still abound at present. There is general consensus between those who support the connection and those who refute it to the effect that the form of electromagnetic radiation – the radiofrequency energy – has the potential to heat and potentially damage human tissues.
In this paper, I seek to provide critical evaluation of epidemiologic evidence that supports the lack of association between mobile phone usage and brain tumors. By use of evidence and critical analysis of available evidence, I posit that there is potential link where the mobile phone is used for an extended period (i.e. more than half an hour per day). This is because the radio frequency electromagnetic fields emitted by the mobile phone would start affecting the tissue in the area where it is held. This position would be supported research evidence pointing to the connection between extended use of cellular phone and brain cancer.
Lack of Connection
The concern over potential association between cellular phone use and the development of brain tumors, both benign and malignant, has attracted a host of epidemiological studies – most of which have found insignificant or no elevated risk for brain cancers or brain tumors. In general, the studies conclude that the radiofrequency energy emitted by cell phones is too low to warrant health issues concern (Kwabi-Addo & Lindstrom 2011, p.211).
In large scale-control studies comparing patients of brain cancer diagnosed between 1994 and 1998: Hardell et al. 1999 (Stockholm and Uppsala, Sweden); Muscat et al., 2000 (New York, Providence, and Boston); Inskip et al., 2001 (Phoenix, Boston, and Pittsburgh) all reached consistent results. Generally, all the studies concluded that none of the brain cancer types considered was significantly associated with mobile phone usage, no link between mobile phone use and specific location of brain tumors, no clear connection between the side the mobile phone was used and the side of head on which brain cancer occurred. A study by Johansen et al., 2001 also found lack of association between brain cancer risk and RF dose basing on the duration of mobile phone use, date since initial subscription, age at first subscription, as well as type of mobile phone used (Abdel-Wahab & El-Masry 2010, p.241).
The lack of connection between cellular phone use and brain cancer is supported by a number of expert organizations. The International Agency for Research on Cancer (IARC), which is a component of the World Health Organization (WHO), recently categorized radiofrequency fields produced by such agents like mobile phones as “possibly carcinogenic to humans.” This has been dismissed by critics as being founded on limited evidence drawn from human studies, weak mechanistic evidence from studies on genotoxicity, impacts on immune system function, cell signaling, gene and protein expression, oxidate stress, as well as research on potential implication of radiofrequency fields on blood-brain barrier.
The American Cancer Society (ACS) has interpreted the IARC classification as alluding to possibility of some level of risk related to cancer, but held that the evidence is weak to be regarded causal, warranting further research. The ACS advice that mobile phone users concerned about their exposure to radiofrequency energy should limit the exposure by considering using ear pieces and limiting their overall cell phone use (Prasad 2012, p.56). Another expert organization – the National Institute of Environmental Health Services (NIEHS) has expressed that the current scientific evidence is not weighty enough as it does not categorically link mobile phone usage with particular adverse health problems, but additional investigation into the issue is needed.
In the same breath, the U.S. Centers for Disease Control and Prevention (CDC) has taken the position that while some studies have expressed concerns pertaining to the potential risks of mobile phone usage, there is yet to be statistical evidence from scientific research as a whole to support strong connection between mobile phone use and health effects (Prasad 2012, p.69). Finally, the Federal Communications Commission (FCC) has expressed that there is lack of scientific evidence to attest that wireless phone usage has the potential of leading to cancer or other health problems such as headaches, memory loss, or dizziness.
The insignificant connection between cellular phone and brain tumors is also pointed to statistics showing that brain cancer incidence along with mortality rate have insignificantly changed in the last decade. In the United States, for instance, statistics indicate some 23,123 new diagnoses and about 14,080 deaths as a result of brain cancer in 2013.
Large scale studies have also been conducted in the recent past and came to the conclusion of lack of link between mobile phones use and brain cancer in general. A part of the Million Women Study that sampled about 79,000 women came to such conclusion in addition to ruling out the association between use of mobile phones and 18 other types of cancer (Kwabi-Addo & Lindstrom 2011, p.156). Specifically, the study found no evidence to link mobile phone usage and risk of giloma an meningioma (the two prevalent types of brain cancer). However, the research noted an elevated risk on acoustic neuroma (a rare type of brain tumor) for women had used cellular phone for not less than five years. In their analysis, the researchers attributed the result to chance, given that they had investigated a number of different types of cancer. It was also argued that if there was an elevated risk of acoustic neuroma as a result of mobile phone usage, there would be increased rates of the condition in the general population, which is not the case (Prasad 2012, p.76).
Similarly, the risk of acoustic neuroma as relates to mobile phone usage has been investigated through six population-based, shared-protocol, and case-control studies in the United Kingdom and four Nordic countries. The researchers concluded that there lacked connection of risk to duration of phone use, cumulative lifetime hours of use, along with number of calls, overall phone use, or for distinct analogue or digital phones (Abdel-Wahab & El-Masry 2010, p.242).
Another large scale study in this area, a Danish study, found no association between cellular phone use with any type of cancer including acoustic neuroma, leukaemia and other brain tumors. The sample of the study (over 420,000 people in Denmark over a period of 35 years) was said to have been mostly composed of mobile phone users of early-generation gadgets that emitted more radiation compared to new-generation phones. The research found that there was no difference in risk of getting brain cancer between patients with brain tumor or other central nervous system disease who used cell phones and similar patients who were not mobile phone users (Wascher 2010, p.46). While other studies have suggested that patients with brain cancer have high probability of developing brain tumors on the particular side of the head they hold their phone to, the overall risk has been concluded to be not any higher. More recent studies have suggested a possible high risk of glioma for the heaviest mobile phone users, but no overall increase in brain tumor.
Supportive evidence
There is a plethora of evidence to suggest the connection between mobile phone usage and brain cancer as there is evidence to the contrary. The mechanism of mobile phones is such that they transmit and receive radio frequency microwave radiation, which have been found to be dangerous and harmful to human health (Ayanda et al. 2012, p.403). These radio frequency are relatively stronger that those of an FM radio signal and a billionth the intensity of an X-ray. A significant part of the radiofrequency emitted by mobile phones has been demonstrated to be absorbed by the human head (Ayanda et al. 2012, p.404).
A 2007 Swedish meta-analysis of available international long-term follow up data was among the earliest reports to cite a positive correlation between mobile phone use and the risk of brain tumor (Khurana 2008, p.8). A study by Lakhola et al. (2007) found about 40 percent increase in a type of brain tumor for individuals who had use a mobile phone for a decade or more. A statistically significant increase in gliomas was not noted to accompany a trend indicating that brain tumor risk over the years with continued mobile phone use (Khurana 2008, p.8).
In a major study, Hardell et al. (2004) found that there was an 8 fold increase in the risk for brain tumors for 20-29 year olds just after 5 years of mobile phone usage. The study also found that those who begin mobile phone usage have are four to five times at greater risk of suffering from malignant brain tumor as compared to their age mates who did not use cell phones (Kundi 2009, p.321). This is particularly worrisome considering that children and teens are bound to have lifetime of exposure to the radio waves, and many of them often sleep with their phones next to their heads of under their pillows.
A 2011 report by the World Health Organization noted that a group of 31 scientists drawn from 14 countries meeting at IARC in Lyon, France had accessed the potential carcinogenic hazards due to exposure to radiofrequency electromagnetic fields, and reached conclusions that mobile phone usage could lead to cancer risk (Ayanda et al. 2012, p.405). According to Zada et al. (2012), the U.S. brain cancer registers are increasingly showing a rise in incidences of frontal and temporal lobe tumors, which are the parts of human brain most affected by mobile phone usage.
In view of the above evidence, it is my general stance in this paper that there is positive correlation between mobile phone usage and brain cancer, specifically where the cellular phone is used for an extended period of time i.e. more than 30 minutes each day. This is because the extended exposure would start impacting negatively on the part of the head that is the head is held against during call time (Prasad 2012, p.73).
It is evident that there currently exist insufficient epidemiological evidence because the bulk of the published clinical research data has been as a result of relatively low-powered research studies. This is especially the case considering that findings from meta-analysis studies (researches which integrate a multiple relatively low-powered studies to realize a more powerful meta study) have shown the correlation between the agent and brain cancer (Wascher 2010, p.95). For instance, a Korean meta-analysis analyzing 23 case-control studies generally found that mobile phone use did not appear to amplify the risk of benign or malignant brain tumors. Nonetheless, on analyzing only 13 highest quality clinical studies, it was established that there was an 18 percent increase in the risk of brain tumors as a result of mobile phone use (Robert 2010, 32).
In addition, the findings of most of these epidemiological studies are determined by the way in which the research studies themselves are designed. In many of these studies, patients with cancer are often asked to recall the frequency and manner of their mobile phone usage, usually many years ago (Prasad 2012, p.89). I find this problematic because, due to known memory issues typical with human beings, a respondent may not be in a position to accurately recall the details pertaining to their past phone usage. Generally, heavy users of mobile phones tend to overestimate their usage while light users often underestimate their use, resulting in an underestimation risk. This translates that true risk is indeed larger that the eventual published risk in most epidemiological studies on this subject.
There is also greater chance that the memory of a patient with brain tumor may be significantly compromised by the condition, rendering his/her feedback on cellular phone use unreliable (Cancer Research UK 2013, p.1). Even greater, there is greater probability for many people to be biased in light of their prior knowledge on the connection between mobile phone use and brain cancer from media outlets, media journals or the public.
My concern for 30 minutes use of mobile phone resulting in brain cancer is strongly supported by a recent case-control study undertaken in Japan. The research findings indicated that the use of mobile phones for as little as 20 minutes per day for a period of five years had positive causal relationship with the increased risk of a type of brain tumor, acoustic neuroma. The causal relationship between the agent and brain cancer is especially strong where an individual is exposed to such high frequency electromagnetic radiation emitting mobile phones (approximately 1900 MHz) on a daily basis for a period of time (20-30 minutes per day) for at least 10 years (Prasad 2012, p.92).
One study by the FDA also strongly support my deposition that mobile phone usage for half an hour or more a day could result in brain cancer on the part of the user. The findings by the FDA were to the effect that using a phone 50 minutes made the brain tissue on the part of the head exposed to the antenna-side to metabolize relatively increased levels of glucose as compare to the tissue of the parallel side of the brain.
Furthermore, the National Institute of Health in a report in a peer-reviewed journal, demonstrated that a single hour of mobile phone use considerably increased the rate of glucose metabolism at the body part closest to the antenna. It was further showed that even regions located far from the phone antennas demonstrated biological effects, attesting that the radiation emitted from the phone has the potential of non-thermal effects on the human brain (Prasad 2012, p.84). In this regard, a mobile phone radiation could stimulate free radicals to detrimental action or trigger some kind of inflammatory reaction with the brain. These have the potential to initiate a series of actions that culminate to tumor development in the brain of a mobile phone user.
Professor Hardell also showed significant increase in the risk of brain tumors because of use of mobile phone or cordless phone use for 10 or more years (Sadetzki et al 2007, p.87). Some of the significant findings of this independent concluded that the risk of brain cancer increased by as much as 5% for every 100 hours of mobile phone use; that the risk of brain cancer increased by 8 percent for every year of mobile phone use; that the risk of brain increased by 280% after 10 or more years of using a digital mobile phone; that the risk of brain cancer increased by 420% for digital mobile phone users who began using while teenagers or at a younger age (Prasad 2012, p.95).
Generally, therefore, it can be deduced that the higher the cumulative hours of codeless mobile phone use, the higher the risk; the higher the number of years of using mobile phone, the higher the risk for brain cancer; the higher the radiated energy from mobile phone use, the higher the risk for brain tumor; the higher the exposure (i.e. use on the same side of the head as the brain tumor), the greater the risk; and the younger the mobile phone user, the higher the risk for brain cancer or tumor (Aydin et al. 2011, p.1273).
As I see it, the current debate pertaining to the effects of mobile phone use on brain cancer risk is just analogous to similar controversies that persisted in early 1960s about the carcinogenic prospective of low-dose ionizing radiation. It is common knowledge that the school of thought denying the carcinogenic potential of the low-dose ionizing radiation prevailed for decades until only recently federal agencies came to admit that it was a significant human carcinogen (Kan et al 2008, p.77). In this regard, it is my believe that it would be a while before pundits positing that there is no connection between use of mobile phones and the risk of brain cancer eventually come to accept the reality. It must be appreciated that such solid tumors as brain tumors do not happen overnight, but rather take a number of years to trigger and form (Röösli et al 2007, p.14). On this ground, one would not be mistaken to predict that the currently disputed associations between extended mobile phone usage and brain cancer will be definitively established in medical literature in the next 5-10 years if appropriate measures are not taken by both the Industry and consumers in time (Aydin et al. 2011, p.1269).
The electromagnetic field exposure limits stressed upon by industry and governments are made from a long-running false premise claiming that a mobile phone’s electromagnetic radiation lacks biological effects on humans except for heating (Röösli et al 2007, p.79). This is often in total disregard of the growing epidemiological and laboratory evidence showing that biological effects due to electromagnetic radiation at relatively too low exposure levels there heating occurs (non-thermal effects). Such evidence are readily available in the BioInitiative Report at www.bioinitiatie.org.
In addition, there is need to appreciate the fact that mobile phones is a new phenomenon that is taking root in society and a great sensation in nature. It is evident that that there has not been much time for researchers to carry out long-term studies pertaining to the effects of mobile phones to our health, with particular focus of their effects on the brain. The established latency time (i.e. the time between exposure and diagnosis) for brain cancer is 30+ years (Sadetzki et al 2007, p.22). In the same sense, it is practically difficult for a generation that has never known life without a mobile phone to objectively believe it may have far reaching side effects. The truth of the matter is that mobile technology continues to explode at unprecedented rates beyond our ability to take note of the safety of the widely accepted products.
Recommendations
In this paper, I propose that we adopt the Precautionary Principle as a guiding principle in dealing the risk of brain cancer as a result of our extended use of mobile phones. Essentially, the Precautionary Principle holds that if there is some degree of evidence that a concern may exist, and low or no-cost actions are within reach, then these actions ought to be considered. If mobile phone use has the potential to induce brain cancer, the potential public health cost are then enormous. It is only reasonable that we take measures to significantly reduce the amount of mobile phone radiation at virtually no cost.
It has been demonstrated by a number of studies that mobile phone radiation decreases with the increasing square distance from the phone. This translates that we can significantly reduce the risk of brain cancer by increasing the distance at which we hold our mobile phones during calls. Similarly, mobile phone users would benefit from using a headset connect to the phone so that they do not always hold the phone directly against the year – this would reduce the absorbed mobile phone radiation by several orders-of-magnitude. In light of the greater vulnerability of younger users to mobile phone radiation, governments and schools should consider posting warning relaying the potential adverse health effects resulting from extended exposure to microwave radiation from phones.
References:
ABDEL-WAHAB, A. G., & EL-MASRY, A. A. A. (2011). Mobile information communication technologies adoption in developing countries: effects and implications. Hershey, PA, Information Science Reference.
Angelo G Levis, Nadia Minicuci, Paolo Ricci, Valerio Gennaro and Spiridione Garbisa, 2011, Mobile phones and head tumours. The discrepancies in cause-effect relationships in the epidemiological studies – how do they arise? Journal of National Cancer Institute 2011; 103:p. 1-13. [http://www.ehjournal.net/content/10/1/59].
Aydin D, Feychting M, Schüz J, Tynes T, Andersen TV, Schmidt LS, Poulsen AH, Johansen C, Prochazka M, Lannering B, Klaeboe L, Eggen T, Jenni D, Grotzer M, Von der Weid NX, Kuehni CE, Roeoesli M., 2011, Mobile phone use and brain tumors in children and adolescents: a multicenter case-control study. Journal of the National Cancer Institute 2011;103:1264-1276.
BOUGHTON, B., STEFANEK, M., & GANSLER, T. S. (2010). Reduce your cancer risk twelve steps to a healthier life. New York, Demos Health.
DEMONTE, F. (2007). Tumors of the brain and spine. New York, Springer.
FRANCIS, R. (2011). Never fear cancer again: how to prevent and reverse cancer. Deerfield Beach, FL, HCI.
Kan, P, et al., Cellular phone use and brain tumor: a meta-analysis. Journal of Neurooncology, 2008. 86: p. 71-78.
KHURANA, V. G. (2008). Mobile phones and brain tumours: a public health concern. Canberra, The Author]. http://www.brain-surgery.us/mobilephone.html.
Kundi, M., 2009, The Controversy about a Possible Relationship between Mobile Phone Use and Cancer, Environ Health Perspect. 2009 March; 117(3): 316–324.
KWABI-ADDO, B., & LINDSTROM, T. L. (2011). Cancer causes and controversies: understanding risk reduction and prevention. Santa Barbara, Calif, Praeger.
LIN, J. C. (2009). Health effects of cell phone radiation. Dordrecht, Springer.
MEHTA, M. P. (2011). Principles and practice of neuro-oncology: a multidisciplinary approach. New York, Demos Medical.
MELNICK, E. L., & EVERITT, B. (2008). Encyclopedia of quantitative risk analysis and assessment. Chichester, West Sussex, England, John Wiley.
OBE, G. (2011). Cancer risk assessment: methods and trenda. Weinheim, Wiley-Blackwell.
OLSEN, J. (2010). An introduction to epidemiology for health professionals. New York, Springer. http://site.ebrary.com/id/10397021.
Prasad, N.K., 2012, Radiation Injury Prevention and Mitigation in Humans. United States: CRC Press.
Röösli M, Michel G, Kuehni CE, Spoerri A. 2007, Cellular telephone use and time trends in brain tumour mortality in Switzerland form 1969 to 2002.European Journal of Cancer Prevention 2007;16:77-82.
Sadetzki, Siegal, Angela Chetrit, Avital Jarus-Hakak, Elisabeth Cardis, Yonit Deutch, Shay Duvdevani, Ahuva Zultan, Ilya Novikov, Laurence Freedman, and Michael Wolf, 2007, “Cellular Phone Use and Risk of Benign and Malignant Parotid Gland Tumors—A Nationwide Case-Control Study,” American Journal of Epidemiology, Vol. 167, No. 4, 2007.
SLEEMAN, J. (2010). Health: the casualty of modern times. Mount Barker, S. Aust, Dragon Lair Publishing.
UMAR, A. (2004). Mobile computing and wireless communications: applications, networks, platforms, architectures, and security. [S.l.], NGE Solutions.
WASCHER, R. A. (2010). A cancer prevention guide for the human race. Indianapolis, IN, Dog Ear Publishing.
