The potential radiation risks of using cell phones have been studied ever since the devices came out. The primary concern around cell phone radiation centers on effects of long-term exposure: Does it cause damage in humans, particularly in areas of the body that are often closely exposed to cell phones?
A recent The Journal of the American Medical Association study with 47 participants evaluated whether cell phone exposure affects the amount of brain activity. The study found that, when compared to people who were not using cell phones, 50-minute exposure to cell phone radiation was associated with increased brain activity in the region closest to the antenna. However, it was acknowledged that the findings are of unknown clinical significance. So, the study found that something is happening when users hold cell phones up to their heads, but it did not detail exactly what is happening, and there was no attempt to leap to a conclusion about possible ramifications.
The results of this study notwithstanding, some studies have linked cell phone radiation to a host of maladies, including: migraines, vertigo, tumors of the salivary gland, brain cancer, tissue damage, and low sperm count. Perhaps one of the most comprehensive meta studies on the topic was released in September 2009 by the Environmental Working Group (EWG). In the report about cell phone radiation (PDF), the group described concerns about some research methods used in some of the studies. The group also had concerns that the funding sources for some of the studies could create a perception of bias in the results. Despite these concerns, the group's "report of reports" indicates there is credible evidence linking cell phone usage with health problems. The group's researchers admit that they have not stopped using their cell phones, but they recommend consumers educate themselves about the potential dangers and purchase devices with low radiation emissions. To this end, the group has created an interactive guide to cell phone emissions, covering more than 1,000 phones currently on the market.
The group uses a standard metric for measuring the radiation output: specific absorption rate (SAR); this measures the rate at which the body absorbs radiation as a function of the power absorbed per mass of tissue. SAR is measured in terms of watts per kilogram (W/kg) and is usually cited in one of two ways: averaged over the entire body or localized over a specific area.
In the United States, the Federal Communications Commission (FCC) requires that all cell phones sold test below 1.6 W/kg. Canada has the same 1.6 W/kg requirement, while consumers that fall under the Council of the European Union can buy phones with a SAR rating of up to 2.0 W/kg.
Multi-frequency phones have different SAR measurements for each frequency. This is due to differences in wavelength of the propagating signal. Different wavelengths have different characteristics. For example, for an iPhone 4 on GSM 850, the body SAR value is 1.11, while for GSM 1900, this value plummets to 0.43. Apple also takes care to note that, in order to meet their published SAR values, you should keep your phone at least 15 mm or 5/8 inch away from your body -- this would mean not putting the device in your pants pocket.
Before I provide lists of high SAR and low SAR phones, I'll point you to some sources of information regarding ionizing and non-ionizing radiation. Cell phones emit non-ionizing radiation, which means that the radiation does not have enough power to eject an electron from an atom through which the radiation passes or move the electron to a higher energy level. At best, the radiation is able to excite electrons in its path. The result: Non-ionizing radiation can heat tissue through which it travels. Here's a site you can use to learn a bit more about some of the negative consequences of exposure to ionizing radiation. It's an interesting read.
Best and worst smartphones in terms of radiation
EWG ranks smartphones from best to worst from a radiation perspective. I've taken their lists and added columns showing you the SAR values when held up to the ear and when worn on the body. This is all about the radiation pattern, so there are different values for each area of the body.
The 10 smartphones with the lowest radiation (December 2010)
|LG Quantum [AT&T]||0.35||0.30|
|Samsung Mesmerize (Galaxy S) [U.S. Cellular]||0.57||0.52|
|Samsung Fascinate [Verizon Wireless]||0.57||0.52|
|Samsung Continuum [Verizon Wireless]||0.70||0.47|
|Samsung Captivate (I897) [AT&T]||0.42||0.70|
|Motorola Devour [Verizon Wireless]||0.45||0.72|
|Motorola Flipside (MB508) [AT&T]||0.50||0.76|
|Motorola Backflip Enzo [AT&T]||0.79||0.62|
|Samsung Transform [Sprint, CREDO] - PCS||0.73||0.71|
|Samsung Transform [Sprint, CREDO] - CDMA||0.75||0.82|
|Garmin-Asus Garminfone [T-Mobile]||0.71||0.91|
The 10 smartphones with the highest radiation (December 2010)
|Motorola Bravo (MB520) [AT&T]||1.59||0.53|
|Motorola Droid 2 Global [Verizon Wireless]||1.58||0.89|
|Palm Pixi [Sprint]||1.56||0.63|
|HTC Magic (T-Mobile myTouch 3G) [T-Mobile]||1.55||1.43|
|BlackBerry Bold 9700 RCN71UW [AT&T, T-Mobile]||1.39||0.67|
|BlackBerry Bold 9700 RCM17UW [AT&T, T-Mobile]||1.55||0.77|
|Motorola DEFY [T-Mobile]||1.52||1.53|
|Motorola CHARM [T-Mobile]||1.43||1.53|
|Motorola Droid 2 [Verizon Wireless]||1.49||1.50|
|Motorola Droid 2 R2D2 [Verizon Wireless]||1.49||1.50|
Food for thought
Is there absolute, concrete evidence that cell phone use causes brain cancer or other specific health ailments? No, but there is proof of increased brain activity; the potential impact of this activity needs much further study before specific data-driven action can be taken. However, that doesn't mean that you shouldn't at least take some reasonable precautions. The EWG provides a number of steps that you can take to protect you and your children. I've outlined some of their recommendations, and listed additional suggestions:
- Keep the phone away from your kids. Playing games on your iPhone is one thing, but letting your four-year-old make frequent calls to grandma could create problems for his developing brain, body, and tissue. Either eliminate or limit use of cell phones for phone calls by small children. I see this advice everywhere and can understand why it's out there.
- Use a hands-free kits or speakerphone whenever possible. Consider using a hands-free kit or, at the very least, your phone's speaker.
- Hold the phone away from your body. I use a holster, which does help to keep my phone a little bit away from my body. Whenever you can, do that; don't store your phone in your pocket, especially if you're male and want to have children (yes, there are studies on that specific aspect of cell phone radiation).
- Watch the SAR value. If you're buying a phone and have narrowed down your choices, buy the one with the lower SAR value. Although any radiation might be bad, a lower SAR value means that it accumulates more slowly.
- Use a landline. At work, don't take constant calls on your cell phone. Instead, forward calls to your cell to your work desk phone, if you're allowed to do so.
The tips above are pretty easy steps to take to protect yourself from the potentially harmful rays of radiation emanating from your hip pocket. I'm certain that there will be further studies on this issue. The recent study showing increased brain activity during cell phone use is compelling evidence that more research is needed to determine the full extent to which people may put themselves at harm through the use of their cell phones. Although I doubt that people will stop using their phones, the first step to mitigating a problem is awareness.
- Radio Frequency Safety (FCC)
- Radiation-Emitting Products (FDA)
- Ionizing & Non-Ionizing Radiation (U.S. Environmental Protection Agency)
- Cell phone radiation levels (CNET Reviews)
- Gupta: Cell phones, brain tumors and a wired earpiece (CNN)
- Cell phones with the lowest radiation levels (CNET News.com, March 2010)
- 20 highest radiation cell phones (CNET News.com, March 2010)
- Radiation threats: The 10 most potentially hazardous smartphones (TechRepublic, September 2009)
Since 1994, Scott Lowe has been providing technology solutions to a variety of organizations. After spending 10 years in multiple CIO roles, Scott is now an independent consultant, blogger, author, owner of The 1610 Group, and a Senior IT Executive with CampusWorks, Inc. Scott is available for consulting, writing, and speaking engagements and can be reached at firstname.lastname@example.org.