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Radiation Causes Cancer in Rats. What About Humans?

An update on the science and how big telecoms emit a deadly smog of radiation

It has been over two years since the National Toxicology Program (NTP) released partial findings from a long-term study of the effects of cellphone radiofrequency radiation (RFR) on mice and rats. As we reported in this column at the time, the report did not suggest a strong link between exposure and cancer in rodents. Nor did it speculate on whether cellphones cause cancer in humans, though the study did acknowledge that cellphone radiation is classified as a “possible human carcinogen” by the International Agency for Research on Cancer (IARC). When a draft of the final report was released in February of this year, the evidence linking cellphone RFR to cancer was still deemed “equivocal.” That’s one step up from “no evidence” in the NTP’s scale of evidence.

In late March, the NTP convened two peer review panels, one to assess the technology used in the study, and one to make recommendations on its findings. The first panel found that the “reverberation chamber technology was adequate” for simulating the effects of cellphone RFR exposure in rats and mice. The second panel voted to accept the “conclusions as written” in the study of RFR exposure on mice, which found “equivocal evidence of carcinogenic activity” from exposure to both Global System for Mobile Communications- (GSM) and Code Division Multiple Access-modulated RFR.

However, in their review of the study on rats, the panel voted to recommend increasing the NTP’s evidence level to “clear evidence” of carcinogenic activity in the male heart, and “some evidence” in the male adrenal gland (GSM only) and brain (gliomas). They also increased the evidence rating regarding the female heart. You can see how they voted on each recommendation and watch the panel discussions, which were recorded live.

This study was one of the most expensive and technically complex of its kind. By itself, the panel’s finding of clear evidence that cellphone RFR causes cancer in rats should have been a major story in the press. From a journalistic perspective, this should have been even more of a headline, given that in the same week that the panel publicized its recommendations, another scientific study published by the Ramazzini Institute in Italy replicated the NTP’s findings on rats, raising the confidence level in the study’s evidence. The director of research at the Ramazzini Institute suggested it was time for IARC to “consider changing the RF radiation designation to a ‘probable’ human carcinogen.”

Yet as The Guardian noted, “Not one major news organization in the US or Europe reported this scientific news.” One of the problems with our media is the tendency to avoid publicizing scientific studies that do not provide reporters with clear-cut answers to questions of cause and effect. In this case, the focus on rats might have seemed less newsworthy than a conclusive study on humans. Many scientists would disagree.

As the former NTP senior toxicologist who designed the study pointed out, from a scientific perspective “it’s unlikely any future study could conclude with certainty that there is no risk to humans from cellphone use.” The key phrase “any future study” implies that science is still working on the answer. The layperson might interpret that as a sign not to worry. The point of the NTP study was to find out if simulated cellphone RFR could possibly produce a cancerous tumor. Like the Ramazzini group, the NTP concluded that it is possible. That’s big news—or should be—because it propels future studies toward the discovery of the mechanism that links cellphone RFR exposure to cancer.

Until that discovery is made, many doubts will overshadow the NTP’s research. A lack of consistent evidence in human-centered epidemiological studies has encouraged a passive response to the NTP findings, largely because there has not been an overall increase of cancerous brain tumors observed since cellphone ownership skyrocketed (though some research has shown tumor-rate increases in areas of the brain next to where people hold their phone). And the widely-cited INTERPHONE study, which found no link between normal cellphone use and brain cancer, employed a case-control method that relied in part on subject interviews. That made the evidence hard to interpret because of implausibly high self-reporting of cellphone usage. Meanwhile, the National Cancer Institute has not tracked benign brain tumors long enough to accumulate meaningful evidence.

Another problem is that the NTP and Ramazzini studies challenge the expectations of scientists who are taught that wireless and cellphone RFR are benign. As Newsweek put it, “Scientists have clung to one reassuring point: According to everything we know about physics and biology, cellphones should not cause cancer. The radio waves they emit are ‘nonionizing,’ meaning they don’t damage our DNA the way ultraviolet light from the sun or X-rays do.” This is a powerful idea that encourages many in the scientific community to sideline research showing a link between cellphone and wireless RFR and a range of health risks, including, inter alia, damage to DNA, reduced sperm count, oxidative stress, and impaired memory. Take a look at commentary by well-educated debunkers and skeptics and you’ll probably find a key part of their reasoning based on this assumption.

Finally, there is the political-economic situation. It gives inordinate power to the wireless and telecommunication industry to define how we think about the health risks of cellphones. For example, the US telecommunication industry has accumulated cellphone usage data over decades but refuses to release it for scientific research. The Cellular Telecommunications Industry Association (CTIA)—the powerful wireless industry trade group—filed lawsuits against the cities of San Francisco and Berkeley when they passed “right to know” ordinances to warn shoppers of RFR exposure risks when carrying mobile phones in their shirt pockets, pants, or bras. San Francisco gave up its effort after losing in federal appeals court. The Berkeley case is still being litigated. CTIA’s lawsuit argues that the warnings violate cellphone merchants’ free speech rights, a move that US Supreme Court Justice Kagan called “weaponizing the First Amendment” against “workaday economic and regulatory policy.

Clearly, CTIA does not want the public to think about the possible risks of cellphone use. This is evident both in its investment to suppress a public warning that merely summarized the Federal Communications Commission (FCC)’s mandated disclosure of radiofrequency risks as well as in the tens of millions of dollars that the association has spent lobbying the federal government on behalf of the telecommunications industry over the last decade.

Speaking of the FCC guidelines on RF exposure, these have not changed since the mid-1990s when the agency established safe levels based on “specific absorption rate,” or SAR, by testing simulated exposure using a model of an adult male skull (SAR levels have never accounted for children’s or women’s risks of exposure). The FCC does not independently test for SAR levels, trusting instead that manufacturers’ self-reported SAR levels are accurate—another example of how the agency has been “captured” by the corporations we expect it to regulate.

The way it’s supposed to work is this: the Food and Drug Administration (FDA) advises the FCC on setting guidelines after reviewing available research. But after the initial draft of the NTP study was announced in February, the FDA was not moved to instruct the FCC to make any changes to the safety guidelines. It remains to be seen how the Administration responds when the final NTP draft is published in the coming weeks.

All of the above presents a worrisome prelude to the seemingly inevitable deployment of 5G technology, which will exponentially increase exposure to radio frequency and electromagnetic fields (EMF). The telecommunication industry is poised to build an extensive network of 5G transmitters, saturating the environment with RF and EMF radiation in service of a new regime of internet-enabled devices known as the Internet of Things. Because radiation from these powerful transmitters can only travel a short distance, they’ll have to be placed close together and in close proximity to people. For some, the prospects are frightening. Last year, over 180 scientists called for a moratorium on 5G because of the health risks posed by adding even more radiation on top of 2G, 3G, and 4G. In the words of Joel Moskowitz, director of the Center for Family and Community Health at the University of California, Berkeley, “people will be bathed in a smog of radiation 24/7.”

Over 95 percent of Americans own cellphones. Our increasing dependence on these devices and the networks that interconnect them give the telecommunications industry and their lobbyists leverage in Washington DC—where all their wishes, so far, have come true. It’s time to shrink the power of the telecommunications industry and its uncontrolled wireless experiment on our bodies. To do so, we need a vigorous and alert form of journalism that can cope with the careful, contingent nature of doing science and does not simply ignore stories without clearly sad or happy endings.

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