While the flurry of anxiety and research related to cellphones and possible links to brain cancer, appears to have largely dissipated, with the COVID-19 pandemic having overtaken many hot healthcare topics, there is possibly more to it in this case, experts say.
They say people might have simply lost interest and, even if there were an association between radiofrequency radiation (RFR) and cancer, would now be unlikely to give up their phones. Or limitations on research could have stifled conversations.
MedPage Today reports that another possibility could be that while animal studies have concerned some experts in the field, others believe studies in humans have all but eliminated their worries. Still others explain that of the many risks for cancer, cellphone use
just isn't one of them.
Even so, there are still areas of research that could be ripe for future findings, such as cellphone use in children, and the move to 5G. Also, the public health lessons from cellphones and brain cancer may prove beneficial beyond the research itself.
To help sort out whether people may still need to be concerned about cell phones and the risk of cancer, MedPage Today asked several experts familiar with the research and the potential considerations in the future.
“It’s becoming more of a quiet area,” said Dr Emanuela Taioli, PhD, of the Icahn School of Medicine at Mount Sinai in New York City, “although it was very intense and controversial five to 10 years ago.”
One reason for the drop-off is that numerous large studies that were being conducted showed no real association between cellphone use and brain cancer, she added.
Notably, the Interphone Study by the International Agency for Research on Cancer was conducted in 13 countries and in 2011 did not find an increased risk of brain cancer from cellphone use.
Other large-scale studies have included a nationwide cohort study in Denmark that found that cellphones do not cause brain cancer, as well as the UK Million Women Study, which also concluded that cellphone use under usual conditions does not increase the incidence of brain tumours.
When those studies were launched, there was interest in conducting large-scale research that would cost many millions of dollars, because, even if the risk was small, “since we are all exposed, the public health relevance would be really high”, Taioli said.
In those early days, there was a lot of concern, she noted. Phones would produce heat, and that was considered a potential sign of radiation entering the body.
Scientists worried what the overall effect would be down the line, she added, but years later, the results from numerous studies, as well as the fact that incidence of brain tumours is decreasing in adults, may have contributed to waning interest.
Of note, research involving cellphone use is inherently hard to conduct.
So much of it relies on self-reporting, Taioli said. It also involves trying to directly measure the use of the cellphone while it’s against the head, she said. Other questions include whether the phone is pointed at another organ, how many hours a day the phone is directly against the head, and how long it has been used in that way.
Though Timothy Rebbeck, PhD, of the Dana-Farber Cancer Institute and Harvard TH Chan School of Public Health in Boston, concurred with certain limitations of large human studies, he said he believed experts in the field view the issue as largely settled.
“My take on it is, when you get to a certain level of human data … the risk that might be conferred by cellphone use is so small,” he said.
There are experts who prefer animal studies because they argue that the epidemiological studies in people have limitations that might prevent researchers from seeing certain outcomes, he acknowledged.
Leeka Kheifets, PhD, of the UCLA School of Public Health in Los Angeles, said that while epidemiological studies don’t really point to a risk, there have been animal studies that were “a bit worrisome”.
The National Toxicity Programme reported that its studies found high exposure to RFR was associated with clear evidence of tumours in the hearts of male rats, as well as some evidence of tumours in the brains and adrenal glands of male rats.
“To better understand the biological basis for the cancer findings reported in the National Toxicology Program'’s earlier cellphone radiofrequency radiation studies, the NIEHS (National Institute of Environmental Health Sciences) built smaller RFR exposure chambers that use a broader range of frequencies, allowing scientists to evaluate newer telecommunications technologies. Studies are being conducted to test the performance and operations of the smaller exposure chambers,” a spokesperson for the NIEHS told MedPage Today.
As far as timing, “some technical issues were identified with the exposure system, delaying the start of both the mouse and rat studies”, the spokesperson added. “Some pilot studies in the newly constructed systems have now been completed, and manuscripts are being developed to share the findings. One of the first papers being developed will focus on the exposure system being used for the studies.”
Kheifets said it might be important to study the effects of the move to 5G, and how that might affect exposure, with more towers and more information being transmitted.
Despite this, Rebbeck said there are others who continue to believe that what is seen in animal models does not reflect what is seen in humans.
Limitations similarly exist in the study of pesticides and chemical exposure – it can be difficult to measure in people, he noted.
However, with cellphone studies, enough of them have been well done, and “we can be pretty sure there isn’t anything that we’re missing”, he added. “I think we can make a policy or public health decision that cellphones don't cause cancer based on the summary of the evidence,” he said.
“Moreover, messaging on the topic is crucial to help put it all in perspective. It’s important to consider the things that really matter when it comes to cancer risk, such as smoking.
“There are things people can do – cancer screening, prevention and vaccines – that really make a big difference. If you’re worried about cancer, there are many other things you can do to reduce your cancer risk, that are real.”
Another area of study that hasn't been thoroughly examined is cellphone use in children, experts said.
“They are more vulnerable in general,” Taioli noted. “General radiation for diagnostic x-rays… we try to avoid them in kids because the organs are developing.”
Children from a very young age now have exposure to cellphones, she said. And that itself may be worth studying.
One thing upon which all of the experts agreed is that much of the concern over cellphones and brain cancer has been all but erased. It’s certainly not often that any of them see people with phones pressed up against their head anymore.
Between head/earphones and text messaging, cellphone use as society once knew it, has virtually disappeared.
The switch may be more important from a public health perspective than meets the eye, Taioli said.
“This is an example where people adopted a healthier behaviour without having official direction or guidance,” she noted. “But people… just by reading and looking at each other, they introduced a healthier way of using the phone. I can’t think of another example of this in the field.”
See more from MedicalBrief archives:
Large study to look at impact of mobile phone use on teenagers
Newest cellphones may pose ‘significant risk’ to pacemakers and ICDs
FDA warning on cellphone effects on implanted medical devices
How to kick cellphone addiction — And other bad habits
Texting doctors allows for better healthcare