vital news to anyone who uses a cell phone. today, world health organization panel took a fresh look at the medical research and concluded that cell phones are possibly carcinogenic. days after dr. sanjay gupta investigated serious questions about the current research on cell phones and cancer. here s a portion of sanjay s report, which aired as recently as last night, foreshadowing today s stunning 180 from the w.h.o. on cell phone safety. if you ve ever put a cell phone to your ear, you should listen to what neurosurgeon dr. keith black has to say. there s no way to say cell phone use is safe. i think that the public has a right to know that there could be a potential risk. the public generally assumes if one is selling something on the market that we have had assurances that that device is safe. to be clear, dr. black s message is at odds with headlines from the largest international study on cell phones in cancer. their conclusion, little or no evidence cell phones
but if you look just one layer deeper into the appendix of that same study, and you ll see something unsettling. turns out participants in the study who used a cell phone for ten years or more had doubled the rate of brain glioma, a type of tumor. and keep in mind cell phone use in the united states has only been popular for around 15 years. back in 1996 there were 34 million cell phone users. today nearly 300 million in use, according to industry figures. environmental factors take decades to see their effect, not a few years. reporter: so if it may take decades to get a clear answer, what can we say about cell phone safety now? scientists here in san jose, california are trying to answer that very question. so one of the things we have to do first is literally put the brain inside the head. exactly. it s very light now. reporter: the fcc requires all cell phones emit below 1.6 watts per kilogram of radiation.
associated with brain tumors. but if you look just one layer deeper into the appendix of that same study, and you ll see something unsettling. turns out participants in the study who used a cell phone for ten years or more had doubled the rate of brain glioma, a type of tumor. and keep in mind cell phone use in the united states has only been popular for around 15 years. back in 1996 there were 34 million cell phone users. today nearly 300 million in use, according to industry figures. environmental factors take decades to see their effect, not a few years. reporter: so if it may take decades to get a clear answer, what can we say about cell phone safety now? scientists here in san jose, california are trying to answer that very question. so one of the things we have to do first is literally put the brain inside the head. exactly. it s very light now.
their conclusion, little or no evidence cell phones are associated with brain tumors. but if you look just one layer deeper into the appendix of that same study, and you ll see something unsettling. turns out participants in the study who used a cell phone for ten years or more had doubled the rate of brain glioma, a type of tumor. and keep in mind cell phone use in the united states has only been popular for around 15 years. back in 1996 there were 34 million cell phone users. today nearly 300 million in use, according to industry figures. environmental factors take decades to see their effect, not a few years. reporter: so if it may take decades to get a clear answer, what can we say about cell phone safety now? scientists here in san jose, california are trying to answer that very question. so one of the things we have to do first is literally put the brain inside the head. exactly. it s very light now. reporter: the fcc requires all cell phones emit below 1.6 watts per ki
cell phone use is safe. i think the public has a right to know that there could be a potential risk. the public generally assumes that, if one is selling something on the market, that we have had assurances that that device is safe. reporter: to be clear, dr. black s message is at odds with headlines from the largest international study on cell phones and cancer. their conclusion, little or no evidence cell phones are associated with brain tumors. but if you look just one layer deeper into the appendix of that same study, and you ll see something unsettling. turns out participants in the study who use a cell phone for ten years or more had double the rate of brain glioma, a type of tumor. and keep in mind cell phone use in the united states has only been popular for around 15 years. back in 1996 there were 34 million cell phone users. today nearly 300 million in use