performed cognitive function tests. There were no changes 

in the subjects  ability to recall words, numbers, or pictures, 

or in their spatial memory, but they were able to make 

choices more quickly in one visual test when they were 

exposed to simulated mobile phone signals. This was the 

only change noted among more than 20 variables 

compared.

3

2

In a study of 209 brain tumor cases and 425 matched 

controls, there was no increased risk of brain tumors 

associated with mobile phone use. When tumors did exist in 

certain locations, however, they were more likely to be on 

the side of the head where the mobile phone was used.

Because this occurred in only a small number of cases, the 

increased likelihood was too small to be statistically 

significant.

4

In summary, we do not have enough information at this point to 

assure the public that there are, or are not, any low incident 

health problems associated with use of mobile phones. FDA 

continues to work with all parties, including other federal 

agencies and industry, to assure that research is undertaken to 

provide the necessary answers to the outstanding questions 

about the safety of mobile phones.

What is known about cases of human cancer that 

have been reported in users of hand held mobile 

phones?

Some people who have used mobile phones have been 

diagnosed with brain cancer. But it is important to understand 

that this type of cancer also occurs among people who have not 

used mobile phones. In fact, brain cancer occurs in the U.S. 

population at a rate of about 6 new cases per 100,000 people 

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