( CNN ) -- Radiation from cell phones can possibly cause cancer , according to the World Health Organization . The agency now lists mobile phone use in the same `` carcinogenic hazard '' category as lead , engine exhaust and chloroform . Before its announcement Tuesday , WHO had assured consumers that no adverse health effects had been established . A team of 31 scientists from 14 countries , including the United States , made the decision after reviewing peer-reviewed studies on cell phone safety . The team found enough evidence to categorize personal exposure as `` possibly carcinogenic to humans . '' What that means is they found some evidence of increase in glioma and acoustic neuroma brain cancer for mobile phone users , but have not been able to draw conclusions for other types of cancers . `` The biggest problem we have is that we know most environmental factors take several decades of exposure before we really see the consequences , '' said Dr. Keith Black , chairman of neurology at Cedars-Sinai Medical Center in Los Angeles . The type of radiation coming out of a cell phone is called non-ionizing . It is not like an X-ray , but more like a very low-powered microwave oven . `` What microwave radiation does in most simplistic terms is similar to what happens to food in microwaves , essentially cooking the brain , '' Black said . `` So in addition to leading to a development of cancer and tumors , there could be a whole host of other effects like cognitive memory function , since the memory temporal lobes are where we hold our cell phones . '' Wireless industry responded to Tuesday 's announcement saying it `` does not mean cell phones cause cancer . '' CTIA-The Wireless Association added that WHO researchers `` did not conduct any new research , but rather reviewed published studies . '' The European Environmental Agency has pushed for more studies , saying cell phones could be as big a public health risk as smoking , asbestos and leaded gasoline . The head of a prominent cancer-research institute at the University of Pittsburgh sent a memo to all employees urging them to limit cell phone use because of a possible risk of cancer . `` When you look at cancer development -- particularly brain cancer -- it takes a long time to develop . I think it is a good idea to give the public some sort of warning that long-term exposure to radiation from your cell phone could possibly cause cancer , '' said Dr. Henry Lai , research professor in bioengineering at University of Washington who has studied radiation for more than 30 years . Results from the largest international study on cell phones and cancer was released in 2010 . It showed participants in the study who used a cell phone for 10 years or more had doubled the rate of brain glioma , a type of tumor . To date , there have been no long-term studies on the effects of cell phone usage among children . `` Children 's skulls and scalps are thinner . So the radiation can penetrate deeper into the brain of children and young adults . Their cells are at a dividing faster rate , so the impact of radiation can be much larger . '' said Black of Cedars-Sinai Medical Center . In February , a study by researchers at the National Institutes of Health , revealed radiation emitted after just 50 minutes on a mobile phone increases the activity in brain cells . The effects of brain activity being artificially stimulated are still unknown . Neurosurgeon and CNN chief medical correspondent Dr. Sanjay Gupta says Tuesday 's announcement , `` dealt a blow to those who have long said , 'There is no possible mechanism for cell phones to cause cancer . ' By classifying cell phones as a possible carcinogen , they also seem to be tacitly admitting a mechanism could exist . '' Manufacturers of many popular cell phones already warn consumers to keep their device away from their body and medical experts say there other ways to minimize cell phone radiation . The Apple iPhone 4 safety manual says users ' radiation exposure should not exceed FCC guidelines : `` When using iPhone near your body for voice calls or for wireless data transmission over a cellular network , keep iPhone at least 15 millimeters ( 5/8 inch ) away from the body . '' BlackBerry Bold advises users to `` keep the BlackBerry device at least 0.98 inch ( 25 millimeters ) from your body when the BlackBerry device is transmitting . '' The logic behind such recommendations is that the further the phone is from the body , the less radiation is absorbed . Users can also use the speakerphone function or a wired earpiece to gain some distance . Users can text instead of talk if they want to keep the phone away from their faces . Finally , cell phones emit the most radiation when they are attempting to connect to cellular towers . A moving phone , or a phone in an area with a weak signal , has to work harder , giving of more radiation . So users can avoid using their cell phones in elevators , buildings and rural areas if they want to reduce their exposure , experts say .
NEW : This means the product will ship as received by the manufacturer, sealed, with all advertised components, and with the manufacturer warranty. It 's in the same `` hazard '' category as lead , engine exhaust and chloroform . Until now , WHO has said no adverse health effects have been established . The cell phone industry maintains that there is no conclusive evidence of danger .