That’s the gist of a report recently released by the World Health Organization’s International Agency for Research on Cancer (IARC), the United Nations body responsible for oncological studies. In the report, IARC scientists have classified mobile phone usage as a possible cause of cancer, meaning that, while the data currently available is still inconclusive, the subject deserves further research before a call can be made one way or another.
The problem with radio waves
The question of whether mobile phone users should worry is a tough one to answer because of the multitude of intricate factors involved. And understanding all the scientific reports can be difficult due to the confusing jargon.
Much of the public controversy that surrounds this problem revolves around the concept of radiation. “When people talk about radiation, it’s often in the context of something they fear: radiation coming out of their microwaves, radiation emitted from nuclear materials, radiation from medical imaging devices and so on,” says Joël Perras, a physicist and software developer based in Montréal, Canada. “However, the term ‘radiation’ can be used to describe any wave or particles that travels through space,” without regard to its effects on human health.
Today’s mobile phones are, essentially, extremely sophisticated radios and, as such, emit electromagnetic waves. Much like the vast majority of radiation that surrounds us – from visible light to AM and FM radio waves – electromagnetic waves do not possess enough energy to interact directly with the tissues in our bodies in a way that can cause direct damage.
“The radiation that mobile phones emit is nowhere near the kind of radiation that x-ray machines, for example, emit,” says Perras. “X-rays […] have much, much shorter wavelengths. Consequently, [they] carry much more energy and thus have much more penetrating power, which is required to be able to image the interior of the human body.”
X-rays and other “hard” waves are called ionizing radiation because they can interact with the human body in a way that leads to the creation of chemical compounds called free radicals that can, in turn, be responsible for mutations and the incidence of cancer.
The fact that the radio waves emitted by mobile phones are non-ionizing, however, doesn’t mean that they are automatically safe. After all, the microwave oven in the average kitchen uses electromagnetic radiation to cook food – something that would definitely not be good for any of your body parts.
Of course, microwave ovens project a lot of radio waves into a small, enclosed space, whereas the power output of mobile phones has been decreasing over time: Today’s average handset produces 0.75W of radiation – less than one thousandth of what you use to cook a bag of popcorn.
Cancer difficult to link
The focus of much of the currently-ongoing scientific research, then, is on whether the radiation emitted by mobile phones is focused enough to be absorbed into the body and cause heating, which could, in the long run, damage human tissue and eventually lead to cancer.
The issue is particularly important because most users still hold their phones close to the head; since the brain is particularly sensitive to external stimuli, even a small amount of heat could lead to medical trouble in the long term.
What makes it challenging to determine if a link between mobile phones and cancer actually exists are the many variables involved. “The incidence of brain tumors is quite small, making it more difficult to study in large numbers,” says Dr. Eric Olyejar, a Radiation Oncologist from Ironwood Cancer and Research Centres, based in Chandler, Ariz. That means “quantifying the lifetime dose each patient received is extremely difficult.” (Oncologists are medical doctors who specialise in researching and treating cancer.)
To make things more difficult, cancer often develops as a result of many different factors. “Family history, exposure to chemicals or radiation, growth defects, the amount of radiation that is actually coming from the phone, amount of time used, proximity to the brain, skull thickness and wave frequency are only a few of the many variables,” Olyejar says.
Part of the problem is also that mobile phones have become so ubiquitous that it’s hard to compare the health of users and non-users. “A control arm that does not use mobile phones would be ideal to serve as a comparator; however, that is virtually impossible in today’s world,” noted Dr. Jack Jacoub, a medical oncologist at MemorialCare Cancer Institute at Orange Coast Memorial Medical Care Centre in Fountain Valley, Calif.
As a result, medical research surrounding mobile phones has, so far, been largely inconclusive. Even the IARC report only classifies handsets as “possible” causes of cancer; the present data, which the IARC calls “limited” in scope, does not allow the nongovernmental body to form a conclusion one way or the other.
“There are many things in our environment that are classified as a possible carcinogens or weak carcinogens,” Jacoub says. “However, when you are talking about five billion people who are exposed to mobile phones, which have become an essential part in how we live, [a possible link with cancer] makes a huge splash.” Mobile phones aren’t alone, though: The list of “possible” carcinogens maintained by IARC includes other everyday items, like coffee, diesel fuel and even some drugs used to battle cancer itself.
Significance to users and industry
The types of cancer identified by the IARC report – glioma and acoustic neuroma – are both connected with the brain. The risk is “a matter of lifetime dose, which likely can be minimised by proximity and time,” according to Olyejar. “Using headsets or speakerphones will certainly decrease the dose via proximity one receives.” Although he hasn’t seen the data on this particular issue, he also adds that “some mobile phones will have more penetration than others and [I] believe that regulations will follow regarding this – so, which mobile phone one chooses will probably be important.”
Given that hands-free usage is becoming more prevalent for reasons unrelated to its possible medical benefits – many jurisdictions now prohibit handset usage in cars for safety reasons, for example – resolving any issue related to cancer concerns may, therefore, simply be a matter of properly educating the public.
This is particularly important for youngsters, who are likely to receive a longer cumulative exposure from mobile phone usage. “Given that the jury remains ‘out,’ one should strongly consider limited mobile phone use by children, given their increased sensitivity to potential carcinogens,” Jacoub says.
This problem could also have significant repercussions on the mobile phone industry at large. If convincing evidence of a link between handsets and cancer is eventually discovered, manufacturers could find themselves in the crosshairs of regulators and lawyers, much as the tobacco industry has in recent years. (Though, to be fair, tobacco companies were aware of the dangers their products presented to human health and tried to hide that information from the public).
In the meantime, should you be worried? Jacoub said that “to be ‘concerned’ may be an exaggeration at this point, as the data thus far has been conflicting with some studies suggesting no risk and others a very weak risk. Rather, people should be aware that there are differing opinions and that indeed there may be a link for rare brain tumors.”
Adds Olyejar: “It appears that there is at least a weak association between mobile phone use and the incidence of benign brain tumors. The correlation is likely quite weak and it is important to remember that there are other factors that contribute to the development of a brain tumor.”
In other words, there is no need to panic, at least until more thorough research has been done. In the meantime, if you are concerned about your health, simple steps like the ones outlined by the FDA can help you minimise your exposure to mobile phone radiation while medical researchers continue in their attempts to collect and analyze data to produce meaningful results.