Cell phones sold in the U.S. vary in terms of their Specific Absorption Rate or SAR, the Federal government's measure of the maximum amount of microwave radiation absorbed by the head or body. A cell phone's SAR is assessed using an artificial laboratory model of a very large adult male. In the U.S., the SAR is measured in watts per kilogram averaged over one gram of tissue. (2) The lower the SAR, the less the user is exposed to microwave radiation.
Users of the twenty highest SAR cell phones sold in the U.S. can absorb up to four times as much radiation in their heads as users of the twenty lowest SAR phones. (3)
Samsung sells twelve of the twenty lowest SAR phones available in the U.S. None of the lowest SAR phones are made by the leading U.S. companies, Apple, Motorola, or RIM Blackberry. (4)
In contrast, thirteen of the twenty highest SAR phones are sold by U.S. companies (eight Motorola and five RIM Blackberry), and none are sold by Samsung. (5)
The new Samsung Galaxy SIII smartphone has a maximum SAR of 0.48 watts per kilogram. (2) In comparison, the SAR for the Apple iPhone 4S is 1.11, and for the Motorola Droid Razr Maxx, it is 1.45. (2)
Among cell phones sold in the U.S., why are those produced by U.S. companies among the highest in user exposure to microwave radiation? It's time for U.S. companies to compete in terms of improving user safety. Moreover, Samsung has demonstrated that enhanced antenna technology can improve cell phone performance while it reduces microwave radiation absorption in the user's head and body. So adoption of this technology is a "win-win" for both the industry and the consumer.
All cell phones sold in the US must have a maximum SAR of 1.6 watts per kilogram averaged over one gram of tissue. Six countries have adopted the U.S. standard including Canada, Taiwan, New Zealand, South Korea, Bolivia, and recently, India. The cell phone industry, however, has been lobbying to weaken the U.S. standard because the ICNIRP or international standard allows up to 2.0 watts per kilogram averaged over ten grams of tissue. Although this may sound like a trivial difference, it is not because measuring radiation absorption over a larger volume of tissue averages out the "hot spots." Adoption of the ICNIRP standard in the U.S. could triple the amount of cell phone radiation absorbed by Americans. (6)
Although many health researchers have questioned the utility of assessing only a cell phone's SAR, this is all that governments currently regulate. Throughout the world, governments want the public to believe that all legally marketed cell phones are safe, and that a cell phone's SAR doesn't matter as long as it meets their certification test. The SAR standards, however, were developed decades ago to protect users only from the acute effects of the heat generated by microwave radiation, and do not protect users from non-thermal effects of cell phone radiation which may cause harm from long term exposure including increased cancer risk and sperm damage. (e.g., 7, 8)
For further discussion of why the SAR is inadequate for protecting your health and simple steps one can take to reduce risk, see the web sites for the Environmental Working Group and the Environmental Health Trust and prior news releases from the UC Berkeley Center for Family and Community Health. (9)
Note (9/4/2012 update): The SARs on the c|net website only pertain to the head SAR. The partial body SAR may be less than or greater than the head SAR. The Samsung Galaxy S3 in our example has a partial body SAR of 1.49 watts per kilogram.
(1) Valentine M. "Embedded antennas reduce handset radiation exposure" Mobile Dev&Design Dec 7, 2006; http://mobiledevdesign.com/
(2) c|net. Cell phone radiation levels. http://reviews.cnet.com/
(3) Average of 20 highest SAR phones is 1.48 watts/kilogram vs. 0.36 watts/kilogram for the 20 lowest SAR phones (see (4) and (5) for data).
(4) c|net. 20 lowest-radiation cell phones (United States). http://reviews.cnet.com/
(5) c|net. 20 highest-radiation cell phones (United States). http://reviews.cnet.com/
(6) “'A mobile phone compliant with the ICNIRP standard of 2.0 W/kg SAR in 10 g of tissue may lead to a 2.5 to 3 times excess above the FCC standard of 1.6 W/kg in 1 g of tissue (i.e., 4-5 W/kg in a cube of 1 g of tissue)'(Gandhi and Kang, 2002)." (cited in Gandhi et al. Exposure limits: the underestimation of absorbed cell phone radiation, especially in children. Electromagnetic Biology and Medicine. 2012. 31(1):34-51. http://www.ncbi.nlm.nih.gov/
“James Lin of the University of Illinois, Chicago, who was recently appointed a member of ICNIRP, has called this proposal to increase the averaging volume from 1g to 10g ‘scientifically indefensible’
(7) Giuliani L. Soffritti M. Non-thermal effects and mechanisms of interaction between electromagnetic fields and living matter. ICEMS Monograph. Bologna, Italy: National Institute for the Study and Control of Cancer. 2010. http://www.icems.eu/
(8) Wolchover N. Radiation Risk: Are Some Cellphones More Dangerous Than Others? Life's Little Mysteries. June 23, 2011. http://www.lifeslittlemysteries.com/
(9) Environmental Working Group. Where is EWG's cell phone database? http://www.ewg.org/
Environmental Health Trust: http://www.saferphonezone.com
UC Berkeley Center for Family and Community Health news releases: http://pressroom.prlog.org/