The following excerpt is from Zapped: From Infrared to X-rays, the Curious History of Invisible Light, by Bob Berman (2017, Little, Brown).
The issue of whether cell phone radiation is putting us in danger has generated much press, some thoughtful, some paranoid. An example of the latter is the widespread belief, expressed all over the Web, that corporations involved in the cell-phone industry (including manufacturers, electronics and software companies, and the carriers themselves), as well as government regulatory agencies and even large mainstream health organizations such as the American Cancer Society and the Mayo Clinic, are actively conspiring to suppress microwave hazards of which they are supposedly well aware.
Some of the fears are based on a report issued in 2011 by the World Health Organization’s International Agency for Research on Cancer (IARC). The agency had gathered in Lyon, France, to discuss scientific studies surrounding the question of whether there’s a relationship between radio-frequency-modulated electromagnetic fields (RF-EMF) and cancer. After intense deliberations, and to the great surprise of the world at large, experts decided to classify RF-EMF waves emitted by cell phones, cell towers, and Wi-Fi networks as category 2B, indicating a “possible human carcinogen.”
On the other hand, as a New York Times article pointed out in 2016, there have been many studies conducted on the issue, including the Million Women Study, in Britain, a Danish study of more than 350,000 cell-phone users, and studies examining the effects of radio waves in animals and cells growing in petri dishes. Those studies indicated that there is still “no convincing evidence of any link between cellphone use and cancer or any other disease. Also, the incidence of brain cancer in the United States has remained steady since 1992, despite the stark increase in cellphone use.”
Between the alarming conspiracy theories, the “possible human carcinogen” verdict, and reassuring reports like the one in the Times, it’s hard to know what to believe, and that in itself can cause anxiety, because we certainly need to know. More than a billion people use cell phones daily. Are our phones putting us in danger or not?
The short answer is probably not, but it’s still better to take certain precautions.
First of all, the microwave and radio bands consist entirely of nonionizing radiations. They simply don’t have the energy to knock electrons out of their orbits, which means they can’t cause changes on an atomic level. So even with prolonged exposure to microwaves or radio waves, there’s no danger of gene mutations or chromosome damage. And presumably there’s no possibility of such rays being carcinogenic.
Indeed, microwaves lie not merely outside the ionizing part of the electromagnetic spectrum but also far from it. Microwaves are less energetic than infrared radiation, which in turn is less energetic than visible light. And nobody can be harmed by, say, red mood lighting, even if it’s bright.
Is it okay to warm up your teenager’s brain? Regardless of whether microwaves can cause cancer (we’ll get to that in a second), we know that they do make atoms jiggle faster — another way of saying they heat tissue. One study showed a measurably increased blood flow on the side of the head where a cell phone was held. The effect was undeniable. But was it deleterious? Might it simply mean that a certain part of the brain had become actively engaged? One might point out that drinking a bowl of soup or enjoying a cup of tea will heat far more tissue, and to a much greater degree, than talking on a cell phone will, yet we don’t worry about the potential health risks of frequent tea drinking. Moreover, taking a single hot shower heats far more body tissue in one shot than using your cell phone non- stop for a month. So this “heating tissue” business is a good example of a real effect caused by radio-frequency radiation that sounds scary but in all probability is inconsequential.
Now to the cancer question: as of 2016, there are more than seven thousand major studies of RF “radiation” in the medical literature. As the Times reported, the very largest studies have failed to detect an association between cell-phone use and brain tumors or other cancers.
The largest investigation is the Interphone Study, which involved thirteen countries, including Canada, the United Kingdom, Denmark, and Japan. Researchers questioned more than seven thousand people who had been diagnosed with a brain tumor as well as a control group of fourteen thousand healthy people about their previous cell-phone use. The study found no association between cell-phone use and glioma (cancerous brain tumor) rates except in the group of participants who reported using their cell phone for at least 1,640 hours in their lifetimes without a headset. Those participants were 40 percent more likely than those who never used a cell phone to have a glioma. Since this finding contradicted other studies that uncovered no increased cancer risk, the Interphone Study authors speculated that people with brain tumors, looking for an explanation for the tragic disease that had befallen them, might be more likely than healthy people to exaggerate their cell-phone use.
Also reassuring are the results of studies involving workers whose occupations expose them to more than a thousand times more RF energy than the rest of us get. These lab technicians, cell-phone-tower maintenance workers, radar technicians, and others show no increased cancer rate whatsoever.