Do cell phones cause cancer? The question has nagged researchers and users for the entire time - roughly the last 20 years - that these phones have been in common use.
The Food and Drug Administration's website states, "The weight of scientific evidence has not linked cell phones with any health problems." The FDA emphasizes that cell phones emit low-level, non-heating radiofrequency (RF) energy, rather than electron-stripping ionizing radiation, the type proven to permanently damage tissues and disrupt DNA.
But damage from RF energy may be cumulative over very long periods. Since cell phones show no signs of going away - indeed, most American children today face a lifetime of exposure - it's vital to focus closely on the most recently published studies, the ones that show the effects of longer-term exposure.
I am not persuaded that the FDA has done that sufficiently.
Recently, the Environmental Working Group (EWG), a Washington, D.C.-based nonprofit organization that advocates for health-protective policies, has reported on key studies (including, crucially, several recent ones, published from 2007 to 2009) that link radiation from long-term cell phone use with increased risks of brain and salivary gland tumors, migraines and vertigo, as well as behavior problems in children, including hyperactivity. Among the findings cited:
- An analysis of 25 earlier studies by two research groups showing a 50 to 90 percent increase in the risk of glioma (a brain tumor that is frequently malignant) on the side of the head favored for cell phone use in individuals who had used cell phones for more than 10 years. It also showed a 60 percent increase in acoustic neuromas, benign but troublesome tumors of a cranial nerve among long-term cell phone users
- A 50 to 60 percent increased risk of salivary gland tumors among people who used cell phones frequently.
- A 10 to 20 percent increased risk of hospitalization for migraine and vertigo among long-term cell phone users.
- An 80 percent increased risk for emotional and hyperactivity problems among young children who use cell phones and whose mothers used cell phones during pregnancy.
All of this sounds very alarming, and it is not good news, but it is important to keep the numbers in perspective. When speaking in terms of a percentage increase in risk, bear in mind that if, for example, one person out of 100 is normally at risk of a brain tumor, a 100 percent increase in risk means that two people out of 100 would be at risk. It does not mean that as a cell phone user, you have a 100 percent chance of developing a brain tumor. The actual risk to a given individual indicated by these studies is quite small.
Still, I believe prudence is warranted.
The EWG report maintains that current U.S. government radiation standards are outdated. It noted that in 2008, the European Parliament passed a resolution urging member countries to develop lower radiation limits for cell phones - no such steps have been taken in the U.S. Here, particular concern is focused on the amount of radiation that could penetrate a child's softer, thinner skull (roughly twice the amount that could penetrate an adult skull) and that long-term cell phone use starting in childhood could pose even bigger risks than those already documented. Experts in the U.S. and Europe have advised limiting youngsters' cell phone use.
Fortunately, the smart response to this report is not necessarily to abandon or even curtail cell phone use, but rather to use them more carefully. The saving grace of cell phones is that, like all point-sources of radiation, they obey the inverse-square law: the strength of an electromagnetic field is inversely proportional to the square of the distance from the source point. This means that if you move the phone twice as far away from your head, you get one quarter the RF; move it three times farther, you get one-ninth the RF. So rather than clasping the phone to your ear (roughly one inch from your brain), use the phone in speaker mode (roughly 15 inches from your brain) and you'll drop the RF to your brain to a mere 1/225th of the against-the-ear dosage.Aside from that, the EWG check list for safe cell phone use is similar the safety tips I've been recommending for some time:
- Save long conversations for land-line phones.
- Use a headset or the speakerphone setting, and keep the phone itself away from your body.
- Find out how much radiofrequency energy your cell phone emits. This measurement is called the Specific Absorption Rate or SAR. The SAR permitted in the United States is 1.6 watts per kilogram. The FCC maintains a list of the SAR of various phone models; the EWG also has a simple tool to check your phone's emissions.
Specific Absorption Rate or SAR. The SAR permitted in the United States is 1.6 watts per kilogram. The FCC maintains a list of the SAR of various phone models; the EWG also has a simple tool to check your phone's emissions.
The EWG also contends that the U.S. government should require phones to be labeled with their radiation emissions at the point of sale. I agree.
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