How safe are cell­phones? Science is mixed

Times Colonist - - Life - W. GIFFORD-JONES The Doc­tor Game

Are some cell­phone users des­tined to de­velop can­cer af­ter years of use? Or is this fear be­ing over­played? For years, I’ve tried to find an un­bi­ased in­for­ma­tive source. Now, a report from the Univer­sity of Cal­i­for­nia at­tempts to an­swer this per­plex­ing ques­tion.

We know that high fre­quency ion­iz­ing ra­di­a­tion from ex­ces­sive X-ray ex­po­sure can pos­si­bly cause ma­lig­nancy. This ra­di­a­tion is cu­mu­la­tive, and like an ele­phant, it never for­gets the amount of ra­di­a­tion re­ceived. But cell­phones emit very low-in­ten­sity non-ion­iz­ing ra­diofre­quency en­ergy that’s gen­er­ally as­sumed to be safe.

Re­searchers at the Univer­sity of Cal­i­for­nia an­a­lyzed sev­eral stud­ies from around the world. They be­lieved the de­bate would be set­tled by the “In­ter­phone Study.” This re­search in­volved 13 coun­tries and the World Health Or­ga­ni­za­tion at a cost of $25 mil­lion. But the re­sults were con­sid­ered in­con­clu­sive, or as they re­ported, “down­right mud­dled.”

It did show that the use of cell­phones 30 min­utes a day re­sulted in a higher risk of a brain ma­lig­nancy known as a glioma. This can­cer oc­curs on the side of the head where the cell­phone is used. The report re­minded me of a case I pre­vi­ously wrote about, of a woman who de­vel­oped breast can­cer af­ter re­ly­ing on her bra to hold the phone.

Crit­ics pointed out sev­eral flaws in the study, which was pub­lished in 2010. They said the data was too old, as the study dated back to the 1990s. More­over, older cell­phones emit­ted dif­fer­ent amounts of en­ergy and ra­dio fre­quen­cies. Peo­ple also used cell­phones less at that time than to­day. And no chil­dren were in­volved in the study.

Then in 2011, the Bri­tish Med­i­cal Jour­nal pub­lished a study of 358,000 Dan­ish cell­phone users. This report showed no in­crease in the risk of brain tu­mours, even in those who used cell­phones for more than 13 years. And an ac­com­pa­ny­ing editorial stated that brain-can­cer rates had not in­creased in Scan­di­na­vian coun­tries.

How­ever, it was not all good news. The same year, the In­ter­na­tional Jour­nal of On­col­ogy re­ported an­other Swedish study. It dis­cov­ered an in­creased risk of brain ma­lig­nancy in those who used cell­phones for 10 years or longer, par­tic­u­larly those who used cell­phones be­fore age 20.

A year later, the same jour­nal had more dis­turb­ing news. A fol­lowup study showed a three-fold in­crease in gliomas when cell­phones were used for 25 years or longer.

But be­fore cell­phone users could get ner­vous, the In­ter­na­tional Jour­nal of Epi­demi­ol­ogy pub­lished the Mil­lion Women Study in the U.K. This showed no over­all in­creased risk for var­i­ous brain tu­mours among cell­phone users. That same year, a French study in Oc­cu­pa­tional and En­vi­ron­men­tal Medicine also re­ported no link be­tween cell­phone use and brain ma­lig­nancy.

The U.S. Na­tional Tox­i­col­ogy Program has re­ported a re­cent study of male rats. For two years, be­gin­ning at the early em­bryo stage, rats were ex­posed to the same ra­di­a­tion as that pro­duced by cell­phones for nine hours a day. Re­searchers found an in­creased risk of two types of tu­mours, in­clud­ing glioma. But rats are not hu­mans, so again the study was ques­tion­able.

So there is still no def­i­nite an­swer and it may be years be­fore an an­swer is known. How­ever, it’s well to re­mem­ber that mil­lions have now been us­ing cell­phones, and dur­ing the last two decades, there has been lit­tle in­crease in brain can­cer. But Ger­many, France, Is­rael, Britain and Rus­sia have nev­er­the­less is­sued pre­cau­tion­ary warn­ings about the use of cell­phones by chil­dren. This is rea­son­able, as the brain is less de­vel­oped at this age.

One thing is cer­tain: Cell­phones are here to stay, and in all prob­a­bil­ity, the risk of brain can­cer is small. This risk can be de­creased by sev­eral mea­sures. Use the speak­er­phone rather than hold­ing the phone next to your ear. Text rather than call. Limit phone use when the bar shows a weak sig­nal, which in­creases ra­di­a­tion. And re­mem­ber that 20 per cent of car crashes (1.1 mil­lion a year in the U.S.) in­volve the use of cell­phones while driv­ing. Cana­di­ans are no smarter.

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