RF energy in the 800MHz and above ranges has been linked to all...

sorts of cancers.
Notably when Motorola first came out with the cellphones that preceded the 'flip phones' there was a very high incidence of brain cancer and tumours in frequent users.
The development of the flip phone and a lot of money spent behind the scenes to stifle the controversy pretty much put the whole issue on the back burner.
Unfortunately the problems haven't gone away

It has gotten to the point now with WiFi, etc. that the incidences of cancer in the groin area have risen drastically...due to the proximity of laptop computers, Pads and other wireless Internet appliances.
An alarming rate of cancers has appeared in the youngest users of these devices; presumably because many of them are still growing and their metabolisms in a fragile state!

There is lots of research and clinical evidence out there if you want to read it

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