April 13, 2005... Could cell phone radiation actually protect against brain cancer? Could it provide “vitamins for the brain”, as one irreverent epidemiologist suggested recently? Such a possibility, however improbable, is not as far fetched as it may sound.

This is not a new idea, but a new epidemiological study, published yesterday in Neurology brings it back to mind. A team led by Chrisoffer Johansen of the Danish Cancer Society in Copenhagen was looking at whether cell phones could promote brain tumors. They did not see an increased risk but did find that users had fewer aggressive tumors than non-users and that, in general, the tumors that did develop were smaller among users. These so-called “regular users” had only a little more than half as many high-grade gliomas as expected. And the tumors were, overall, 25% smaller.

The Danish study is the second brain tumor study to appear from the Interphone project, which is being coordinated by IARC, the International Agency for Research on Cancer in Lyon, France. (In all, 13 countries are participating). Maria Feychting and coworkers at the Karolinska Institute in Stockholm published their results last month in the American Journal of Epidemiology (AJE). They also saw fewer gliomas among cell phone users, though this difference was not statistically significant. While the Danes observed the greatest protection for the high-grade gliomas, the Swedes found it for the low-grade, or less aggressive, gliomas.

Since the Karolinska paper appeared on March 15, there has been much talk among epidemiologists about the fact that practically all the observed risks were smaller than expected. Amazingly, in one table (Table 2) presenting approximately 50 different categories of cell phone use, the Swedes found only a single risk above unity. (A relative risk of one signifies no effect; without a protective or deleterious effect, one would expect to see the risks randomly distributed above and below one.)

Sam Milham, the well-known epidemiologist, was the first to spot the skewed distribution of observed risks in the Swedish paper and has pointed this out in a letter which will appear in the AJE. If cell phones are not protective, then there was some kind of bias in the way the Swedes collected their data. This could mean that the whole study is faulty, calling into questions their conclusion that cell phones are not linked to brain cancer. Indeed, Milham believes that the Karolinska study points to a brain tumor risk on the same side of the head as a phone is used.

What’s so tantalizing about these two sets of findings is that there is some experimental evidence to support a protective effect. More than 15 years ago, Steve Cleary of Virginia Commonwealth University in Richmond showed that microwaves could either stimulate or suppress the growth of human glioma cells exposed in a laboratory setting. The direction of the effect depended on the intensity of the radiation (see MWN, M/A90)

To be sure, Cleary used some relatively high power levels in his experiments, but Jerry Phillips, in some experiments sponsored by Motorola, later showed a similar delicate balance between beneficial and deleterious effects in experiments on RF-induced DNA breaks. Phillips exposed human cancer cells at intensities that are common for users of cell phones (see MWN, J/F98).

A number of animal studies have also pointed to a protective effect The most notable of these was the experiment run by the late Ross Adey for Motorola (see MWN, M/A96 and J/A96). In essentially all these cases, the protective effect has been due to digital or pulsed microwave signals. (For an overview of these studies, see MWN, S/O02.).

The Danes and the Swedes who participated in the newly published epidemiological studies mostly used analog phones —at least in the early years. So one should be careful before jumping to any conclusions, but the results are provocative and should, we would hope, stimulate some interesting experiments. That is of course, if there is any money for follow-up work, always a dicey proposition.

The Danish group dismisses the possibility of a protective effect because of a lack of a “biologic plausibility.” But we would counter that many say that there is no biological plausibility for a detrimental effect.

Until we better understand what’s really going on, we are in uncharted waters and all possibilities should be considered. These two epidemiological studies and the others due from the Interphone project are only a preliminary picture of the long-term impact of cell phone use. So far at least, they have included only a small number of subjects who have used phones for ten or more years, with substantial air time over that period.

[It is worth noting that the definition of a “regular user” of a cell phone in all the Interphone studies is the use of a mobile phone on average once per week during at least six months.” Today, mobile phone companies routinely sell plans that allow thousands of minutes per month.]

The issues discussed here go far beyond hazard research. They raise fascinating questions about basic science that need to be answered. We shall see if anyone out there is interested in science or if this is really all about telling people that it’s okay to keep using their mobile phones.

April 8, 2005... Fire fighters want to know if placing cell phone towers on fire stations puts them at risk. Until a study can provide some reassurance that there is no radiation hazard, the International Association of Fire Fighters wants to ban antennas from fire stations.

We wish them luck, but we bet that the study will never get off the ground. In any case, if an epidemiological study were to be done, this is not the one to do.

The fire fighters’ appeal reminds us what happened when, some 15 years ago, police officers asked the government to look into allegations that radar guns could cause cancer. The police had some powerful friends. Democratic Sens. Chris Dodd and Joe Lieberman asked the NIEHS and the NIOSH for an epidemiological study while the International Brotherhood of Police Officers campaigned for a ban on the use of radar guns. At a Senate hearing held on August 10, 1992, representatives from government, industry and academia all voiced support for a study.

“Senator Dodd and I are going to stick with this until we get some answers,” Lieberman promised that day. Space hero Sen. John Glenn showed up and said that he was “extremely disturbed” by the reported link between police radar and cancer. And Dodd urged the NIH to get on with it because his patience was “about to run out” (see MWN, S/O92). That summer, the controversy was featured on a segment of 60 Minutes. But nothing ever happened. There was no study, there was no follow-up. The next summer, an epidemiologist and a pathologist jointly reported in the American Journal of Industrial Medicine an abnormal clustering of testicular cancer among police officers who had used hand-held radar guns (see MWN, J/A93). But that also failed to prompt any action from NIH. And five years later, the same journal published a paper pointing to a link between both testicular cancer and skin cancer (melanoma) with radar guns (see MWN, J/A98). Again, nothing happened.

The fire fighters have a much tougher battle than the police officers because very few people think it’s worth spending the money to investigate cancer rates around a cell site. If they really want a study, the union will have to pay for it. But even if the fire fighters pony up the money, it’s unlikely they will get any reliable answers. These types of studies are notoriously hard to do and, in this case, it will be even more difficult because the microwaves from cell towers are not very strong. It will be a torturous task to untangle all the various factors at work.

We must believe that the fire fighters have been warned about how hard the epidemiology will be. And that they have been told that it would be much easier to study those who use hand-held phones. After all, it’s essentially the same type of radiation and although the exposures from the phones are intermittent, their intensity is approximately a thousand times higher.

Another approach would be to study radio and TV towers, which broadcast much stronger radiation signals. That was the logic of Bruce Hocking, who once was the chief medical officer of Australia Telecom (later called Telstra). He wanted to show that cell towers were safe and figured that if he could show that TV towers were not associated with cancer, he would reassure the locals who were fighting cell towers. It did not turn out the way he expected. He found higher rates of leukemia among children living near the TV antennas in Sydney (see MWN, N/D95).

To no one's surprise, a controversy erupted and no one dared to repeat the study. This too is unresolved.

As long as each group limits itself to a special case, there will be no answers. Progress will only come when the various factions understand that they have common interests. A useful first step would be for the firefighters to look beyond the towers and ask for studies of cell phone users. In the long run, that’s their only hope of finding out whether those antennas are safe.


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