This May, the World Health Organization formally classified the electromagnetic fields produced by mobile phones as “possibly carcinogenic to humans” based on the Interphone study conducted by the International Agency for Research on Cancer (IARC). This declaration has further fanned the flames of worry about the link between cell phones and cancer. Though the results of the Interphone study (released in spring of 2010) were inconclusive, the possibility of a link could not be ruled out by the data.
Even though organizations—including the American Cancer Society, the Centers for Disease Control, the Food and Drug Administration, and the Federal Communications Commission—agree that more study is needed and that no definitive evidence that cell phones cause cancer exists, consumers remain concerned. Should you take steps to protect yourself from the risks, even if they’re minimal? Or should you just tune out the debate until someone has a definitive answer?
According to a World Health Organization fact sheet, “To date, no adverse health effects have been established as being caused by mobile phone use.” So what’s up with the carcinogen classification?
In an interview last year, one of the Interphone study’s authors, Dr. Daniel Krewski, noted that even though part of the data suggested an increased risk of a type of brain tumor, the data used to reach that conclusion was partially flawed. That’s because the study’s participants guessed how much and how often they used their phones. Still, the indication of some link—even with the questionable data—was enough to warrant continued concern and further study.
Another factor is that the study began in 2000, when there were about a third as many cell phone users as there were in 2010 (based on data from the CTIA). The usage pattern—amount and frequency of calls—has also changed in that time. How that will affect current users isn’t known, and may not be known for 20 to 30 years.
Until more studies are conducted, the WHO is erring on the side of caution, stating that the classification is used “when a causal association is considered credible, but when chance, bias or confounding cannot be ruled out with reasonable confidence.”
As you might expect, the wireless industry is less than thrilled with the WHO’s carcinogenic classification for mobile phone radio frequency fields. John Walls, vice president of public affairs for CTIA, released a statement dismissing the significance of the IARC’s findings, noting that pickled vegetables and coffee had received similar classifications in the past.
Mobile phones use radiofrequency (RF) energy, which is a non-ionizing type of radiation. Ionizing radiation, found in X-rays, does pose a known cancer risk. Biologically, the only known and proven effect of RF energy is heat. And the level of non-ionizing radiation that cell phones generate apparently can’t raise a person’s local body temperature significantly.
However, scientists are currently looking at the myriad ways in which RF energy could affect the body. For instance, there’s one study attempting to measure how much the signals affect brain glucose metabolism, which marks brain activity, published in the Journal of the American Medical Association. One study sponsored by the European Union suggests that non-ionizing radiation can be harmful to DNA.
The Mayo Clinic recently listed heavy mobile phone use as a possible risk factor for acoustic neuroma, a non-cancerous tumor that develops in the inner ear. But a recent study out of Denmark published in the American Journal of Epidemiology found that people who used a cell phone for 11 to 15 years were no more likely to develop an acoustic neuroma than those who had never used a cell phone.
Of course, each study comes with the familiar caveat that the findings aren’t conclusive and that more research and time are needed.
An article titled “Mobile Phones, Brain Tumours and the Interphone Study: Where Are We Now?” published in the July 2011 issue of the Environmental Health Perspectives journal concluded that the evidence is “against the hypothesis that mobile phone use can cause brain tumours in adults” while admitting that there is some uncertainty. The article’s authors based this conclusion on close examination of the Interphone study, and their main criterion for dismissing the cancer/cell phone link was the methodology, which the WHO has already admitted is problematic.
Dr. Devra Davis, founder and president of Environmental Health Trust, believes that not enough attention is being paid to studies that draw more conclusive links between RF energy and adverse effects on the body. She has also pointed out that part of the funding for the Interphone study was provided by wireless companies, and she suspects that scientific data pointing to the dangers of cell phone use is being suppressed or unfairly maligned by the wireless industry.
The WHO has defended its use of money from the wireless industry by noting that a third-party organization served as a buffer between the organization and the study authors to avoid any influence.
In the end, Dr. Davis admits that we don’t know the full extent of the danger right now. And though the ACS, CDC, FCC, and FDA all emphasize that the risks are unknown and unproven, each agency offers advice to consumers for minimizing their exposure to RF energy.
Cell phone manufacturers include warnings in the (often-unread) user manuals that advise consumers to use handsets at a certain distance from the body. It should be noted that every phone’s SAR rating is based on tests that measure the RF absorbtion in multiple scenarios, including when held against the head. Phones cannot exceed the FCC limit at any distance. However, the SAR limit was established in 1996 and is based on an “average” adult human body. What about children?
A recent study published by the National Cancer Institute suggests that cell phone use doesn’t the increase cancer risk for kids. When comparing the cell phone habits of nearly 1,000 children and adolescents between the ages of 7 and 19 in Western Europe, researchers found that regular cell phone users were no more likely to have developed a brain tumor than those who had never used a phone.
Because most study participants had only been using cell phones for about four years, some experts believe that this period may not be sufficient to determine the risk of cancer. As per usual, scientists recommend continued monitoring.
The amount of information on cell phones and cancer is overwhelming and confusing. Given all this data, what should consumers do? “I suggest being prudent and erring on the side of caution,” says Mark Huffman, contributing editor at ConsumerAffairs.com. “The unfortunate thing is that the studies come out and they’re treated in the news cycle. [Consumer advocates] probably do need to step back and do a more comprehensive take on it.”