Can Cell Phones Really Cause Cancer? A Look at Recent Studies

Last Updated on October 2, 2023

As the prevalence of cell phones and wireless technology only continues to become more widespread, scientists are recognizing the need to explore the role of electromagnetic field radiation (EMF), and cell phone radiation in particular, in the development of certain cancers.

Over the past decade, evidence has shown that habitually making calls on a cell phone may encourage the growth of tumors in the brain and nervous system.

Recent research on cancer rates seems to support this possibility: a study published earlier in 2018 found that the incidence of glioblastoma (an aggressive malignant brain tumor) in the United Kingdom has more than doubled from 1995 to 2015.

Rise in Cancer Rates

Though modern medicine has allowed us to triumph over many ailments that once were considered deadly, some diseases have actually become more common, particularly in first-world countries.

Cancer is one of these–currently, it is the second leading cause of death for people of industrialized nations (with only heart disease placing higher on the list)–and research done at the University of Manchester suggests that in earlier millennia, these genetic mutations were very uncommon indeed.

Researchers studied hundreds of mummified remains from ancient Egypt and found only one incidence of cancer; references to the disease in literature from the time period were also rare.

According to professor Rosalie David, this suggests that cancer is “a man-made disease, down to pollution and changes to our diet and lifestyle”.

Many refute this connection by instead attributing the rise in cancer rates to the fact that we’re living so much longer than we did back then (ancient Egyptians would be lucky to make it to their early thirties!). The inevitable result of a longer lifespan is more chances for errors to occur as our cells continue to replace themselves.

Given enough time, these errors can build up in our bodies and become unchecked, eventually resulting in a tumor.

Though growing older undoubtedly increases cancer risk, this fails to explain the rising rates of cancer in children and adolescents.

In 2016, the National Cancer Institute found that in children 19 and under, cancer rates have increased by 27 percent since 1975. And for children, brain and nervous system tumors are the second most common type.

Though it is still rare for a child to be diagnosed with cancer (they only account for 1 out of every 100 new cases in this country), the fact that we’re seeing such a significant increase in a population that is lacking the disease’s greatest risk factor means it’s likely that environmental factors are to blame.

Recent Findings: Malignant Tumors in Exposed Rats

In 2018, the National Toxicology Program (NTP) published the findings of a 10-year study that exposed roughly 3,000 rats and mice to varying levels of cell phone radiation.

The study was conducted to test the widely-held assumption that cell phone radio frequency radiation could not cause cancers or other adverse health effects because non-ionizing radiation didn’t contain enough energy to break chemical bonds in our cells.

The NTP labeled this research as ”the most comprehensive assessment, to date, of health effects in rats and mice from exposure to RFR.”

The subjects were exposed to Radio Frequency (RF) radiation in 10-minute increments for 9 hours a day, using 2G and 3G frequencies and modulations. Exposure levels varied, with the study’s lowest threshold equal to the highest level currently permitted for local tissue exposure to cell phone radiation in humans.

This was based on the same criterion used by the Federal Communications Commission (FCC) to establish exposure guidelines for radio-frequency radiation.

The study found that male rats, in particular, had higher incidences of malignant schwannoma (a rare type of tumor that grows in the tissue surrounding nerve cells) of the heart, which positively correlated with increasing exposure levels. In rats of both genders, heart tissue damage was also observed, as well as the occurrence of tumors in the brain, prostate gland, liver, and other organs. And in female rats, newborns and their mothers had lower body weights when exposed to high levels of RF radiation during pregnancy and lactation.

Scientists at the Ramazzini Institute found similar results when they tested 2,448 rats with radio frequency radiation over their lifetimes. The male rats exposed to the highest exposure of radio-frequency radiation also were significantly more likely to develop tumors in Schwann cells in their hearts.

Though NTP researchers say their study’s findings cannot establish a direct causal relationship between RF radiation and the malignant schwannoma found in the rats, they do mention that the association is very strong and the evidence is clear. A panel of academics and pharmaceutical industry experts reviewed the findings and in March concluded that, in the case of male rats, it showed “clear evidence of carcinogenic activity.”

In NIH’s news release, NTP senior scientist John Bucher said, “We believe that the link between radio frequency radiation and tumors in male rats is real and the external experts agreed.”

The NTP findings demonstrate that the assumption that non-ionizing radiation cannot cause adverse health effects is wrong. Even at the highest levels, body temperatures never rose more than 1 degree Celsius, so the scientists could rule out heating as a cause of any damage from radio waves. It shows that biological changes do exist, regardless of the thermal heating of cells–initially thought of as the only way non-ionizing radiation could do damage.

Learn More about Cell Phone Radiation

Comparative Studies in Humans

The NTP rat study discovery is especially concerning to the researchers because epidemiological studies have already shown that heavy cellphone users are more likely to develop rare brain tumors in the same kind of cells.

Scientists in Sweden analyzed and pooled the results of two case-controlled studies of cell phone use in relation to the development of glioma, the most common type of malignant brain tumor.

The subjects ranged from 20-80 years of age, and data on habits regarding mobile phone use (average minutes of daily use, preferred ear, what type of phone was used, etc.) was collected via questionnaire. The latency period (the time elapsed from the first year of mobile phone use to the time of diagnosis) ranged from 1 year to greater than 25 years.

It was found that both long-term and heavy use of mobile and cordless phones corresponded with greater risk for developing a malignant brain tumor. On average, the subjects developed glioma within 8 years of first use. 3G phones appeared to carry a greater risk than older wireless phones, although unfortunately, not enough time has passed for long-term analysis of their effects. Ipsilateral phone use (primarily holding the phone to one ear instead of switching between both) also increased cancer risk.

The chances for glioma development were highest in those who had started using wireless phones before the age of 20. This is likely because children and adolescents have thinner skulls, smaller heads, and their brains are still developing and thus more susceptible to neurotoxins.

In light of these findings, Swedish researchers concluded that the study “clearly shows an increased risk for glioma associated with the use of both mobile and cordless phones, a risk that increased significantly with latency and cumulative use.”

Another relevant study published in 2014 looked for a possible link between vestibular schwannomas (a slow-growing tumor that develops on the vestibular nerve, which connects the inner ear to the brain) and cell phone usage.

The study included 119 patients who had undergone surgery to remove the schwannomas, and like the Swedish study, data was collected on their mobile phone habits through a series of questions about past use. The subjects’ MRI scans were also examined for differences in tumor growth patterns and characteristics.

The results were similar to those of the Swedish survey: the schwannomas in those who used cell phones regularly (defined as at least once a week for 6 or more months) were significantly larger than those found in non-regular users. And within the regular-use group, those who used their phones heavily (20+ minutes of talk time daily) had higher tumor volumes than those who talked on their phones less frequently.

All of this suggests that exposure to RF EMF radiation from mobile phones encourages the growth of existing CNS tumors. Whether or not it increases one’s chances of developing a tumor in the first place is less clear.

Researchers speculate that the thermal energy transferred to tissues near an existing schwannoma (which takes place when we hold the phone to our ear for extended periods) may encourage the tumor to grow more quickly.

Watch Video: Biological Health Effects of EMF Radiation from Wireless Mobile Devices

Until We Know More, It May Be Safer to Assume the Worst

Though more research is needed to establish a cause-and-effect relationship between cell phone use and cancer, what we already know about EMFs and cell phone radiation indicates that we should apply the precautionary principle. If an activity raises threats to human health, precautionary measures should be taken even if there isn’t overwhelming scientific evidence to support it.

The fact that the rats in the NTP study experienced higher rates of malignant tumors at exposure rates only slightly higher than what is considered safe for humans is a cause for concern.

This is even truer when we recall that the standards for safe levels of human exposure are all but obsolete.

Henry Lai of the University of Washington, who has studied the biological effects of EMF emissions, states that “The SAR rating itself is not meaningful…What we really need to know is at what level we begin to see biological effects. And there are several published studies suggesting it’s at much lower levels than what the FDA or FCC says is safe.”

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