Sept. 9, 2009 -- Recent scientific studies linking cell phone use with health effects such as brain cancer are showing increasing evidence of harm, according to a report by the Environmental Working Group (EWG), a public health advocacy group based in Washington, D.C.
However, other experts roundly criticized the report as a one-sided effort that focuses only on evidence linking mobile phone use with ill health effects while ignoring studies that found no ill effects.
Even so, EWG scientists say there is cause for concern. ''Recent studies are showing a 50% to 90% increased risk for two types of brain tumors -- gliomas and acoustic neuromas -- among people who have used cell phones for at least 10 years," says Jane Houlihan, EWG's senior vice president for research.
"Studies in the past few years are showing a higher risk for brain tumors," she tells WebMD, prompting the EWG to review the scientific literature and issue its report, which also urges the federal government to require that mobile phones be labeled with radiation emission, among other actions.
Still, Houlihan tells WebMD, "The science certainly isn't definitive. The question of whether cell phone use causes tumors and cancer is considered to be inconclusive."
More than 4 billion people worldwide use mobile phones, according to the report, which analyzed more than 200 peer-reviewed studies, government advisories, and industry documents.
In the review of scientific evidence, EWG scientists found recent studies linking cell phone radiation to:
- Brain tumors, specifically gliomas and acoustic neuromas.
- Tumors of the salivary gland. In one study, an increased risk of 50% to 60% was found among those who used cell phones the most.
- Behavioral problems. In one study of more than 13,000 Danish children, an 80% increased risk for emotional problems and hyperactivity was found for young children who used cell phones and for those born to women who used them while pregnant.
- Migraines and vertigo. In a study of more than 420,000 Danish adults, long-term mobile phone users were 10% to 20% more likely to be admitted to the hospital for vertigo or migraine, compared to those who used cell phone for less time.
EWG Ranks Cell Phones by Radiation Emission
EWG's scientists say they are still using their cell phones, but they suggest consumers buy phones with the lowest radiation emissions.
The EWG issued a mobile phone guide, rating more than 1,000 cell phones on their radiation emissions. A high ranking on the list does not mean the phone is the best or the safest, but simply that the phones had the lowest emissions among the models for which data were available.
Here are the phones on the top 10 list for lowest radiation emissions:
- Samsung Impression
- Motorola RAZR V8
- Samsung SGH-t229
- Samsung Rugby
- Samsung Propel Pro
- Samsung Gravity
- T Mobile Sidekick
- LG Xenon
- Motorola Karma
- Sanyo Kantana II
The popular iPhone 3G landed about midway on the complete list. Data on emissions for several phones were not available, the EWG says.
Much lower on the list, the phones with the highest radiation emissions were:
- T-Mobile Shadow
- Motorola W385
- Blackberry Curve 8330
- T-Mobile myTouch3G
- Motorola MOTO VU204
- Kyocera Jax S1300
''There has been a flurry of attention from advocacy groups regarding cell phones and cancer," says Michael Thun, MD, the emeritus head of epidemiology research for the American Cancer Society, who reviewed the report for WebMD.
The conclusion that evidence of ill effects is rising is faulty, he tells WebMD. "Basically the idea that there is a sea change in the evidence in the past two or three years is incorrect," he says. "Essentially this report focuses on studies that support their hypothesis that cell phones increase brain cancer risk. The description of the evidence selectively emphasizes the studies that suggest the risk and omit the evidence that suggests no risk."
As for the argument that earlier studies finding no ill health effects from cell phone use were not conclusive because they didn't examine long-term use, Thun points to Sweden, ''the country that has had the longest cell phone use. And there is no increase in brain cancer in Sweden."
That's true, he says, although the percent of the population there using mobile phones increased over the past two decades.
Even so, Thun says the report's conclusion -- that more government regulation of mobile phones is needed -- is reasonable.
On its web page, the American Cancer Society notes that "cell phones wouldn't be expected to cause cancer because they don't emit ionizing radiation." Says Thun: "It's nonionizing. It doesn't break up DNA."
In the view of the American Cancer Society, Thun says, those concerned about cell phone use can choose to use a corded or cordless earpiece. ''Exposure [to the cell phones' electromagnetic waves] comes from the antenna. If you are using an earpiece, you are getting virtually no exposure.''
Despite his criticisms of the report, Thun says continued research on cell phones and health effects is crucial. "The issue is important," he says. But, he adds, ''this report presents a one-sided view of the evidence. Going forward, it is important that people who are concerned know they can limit their exposure by using an earpiece. It's also important that surveillance be continued and that evidence be reviewed in its entirely in a process that is able to look critically at the evidence."
''As yet the scientific evidence for harm isn't there," he says. "The evidence at this point does not suggest we need a sea change in the way we approach cell phones."
A prepared statement attributed to John Walls, vice president of public affairs for CTIA--The Wireless Association, the industry group for cellular phones, says in part: ''The peer-reviewed scientific evidence has overwhelmingly indicated that wireless devices do not pose a public health risk.''
CTIA points to the opinion of health organizations such as the American Cancer Society, which concur with its view.