Until recently, cell phones were used largely by adults.  However, for a number of reasons they’ve become increasingly common among children, starting with high-school students and working down to younger children.  Now, a bioengineering professor at the University of Washington is suggesting that parents should think twice before giving their children cell phones. 

Dr. Henry Lai states that “we don’t know very much about the health effects of cell phone use on kids, but there are speculations.”  Among these speculations are concerns that most of the energy given off by cell phones is absorbed by the head, and Dr. Lai worries that because children’s skulls are thinner, they may provide less protection to the growing brain.  It’s estimated that brain tumors may take 30-40 years to develop, so people who begin cell phone use early in life would have a longer period of exposure during their lifetimes, which could lead to a potentially greater impact of any adverse health effects.  (Associated Press, March 21, 2005)

…And Another Reassuring Study In Adults

 To determine whether long-term use of cell phones increases the risk of brain tumors, researchers in Sweden identified adults with newly-diagnosed brain tumors (gliomas and meningiomas) and then interviewed them about their past cell phone use; for comparison, they conducted the same interviews among a similar number of adults, from the same regions of Sweden, who did not have brain tumors.

 The authors found no evidence that cell phone use increased the risk of either kind of tumor, and they found similar results when they looked at people who had used their phones for more that 10 years.  They also looked at risks according to the type of tumor tissue, the type of phone, and the amount of time people spent on the phone—and none of those risks was increased. 

The study included a large number of long-term cell phone users, and for these reasons the authors conclude that “the data do not support the hypothesis that mobile phone use is related to an increased risk of glioma or meningioma.”  (Lonn S et al: American Journal of Epidemiology, March 15 2005, pp. 526-534)

COMMENT:  This study from Sweden was conducted by the same authors who last fall reported an increased risk of another kind of tumor (called acoustic neuroma) on the side of the head where cell phones were usually held; this risk was observed after at least 10 years of use.  The experience from the Swedish group reflects what other researchers have found--most studies of brain tumors have been reassuring, but there have been occasional studies that are not.  As a result, many experts consider the debate still open on this subject.  But while the debate goes on, it’s useful to keep in mind that when something poses a very strong health risk, such as smoking and lung cancer, that risk is found by almost every study that’s undertaken; on the other hand, when results are inconsistent, as is the case with cell phones, it’s a pretty good bet that even if there does eventually prove to be a risk, it isn’t likely to be very large.

But what about use of cell phones by children?  As Dr. Lai pointed out, children’s brains may be more vulnerable to the effects of cell phones, and if kids use cell phones from the time they’re 10 years old, they have that many more years of likely exposure ahead of them.  The largely reassuring information we have to date applies to adults—we don’t know that it applies to children.  Since use of cell phones among children is a relatively new thing,  we don’t have enough long-term follow-up research to know what effects—if any—such use will have.

It’s not just kids who ask for cell phones; many parents feel they provide important security value for their children.  As a result, we expect that cell phone use will likely increase among children in the coming years.  Until we know more about their possible risks, perhaps the logical compromise is to encourage the use of ear buds or other devices that put some distance between the phone and the child’s head.  Encouraging kids to keep their phones in backpacks or handbags seems like a good approach to us.