My personal opinion is that there may be a higher risk in some people but not necessarily a direct causation in all brain tumors. Cell phones are so ubiquitous and a big part of the economy, there is a vested interest in opposing the results of any study.
Several years ago, phones were even rated as to the power they emitted. It stands to reason that maybe users might want to be more careful just in case.
Most of us are exposed to many other emissions of radio waves due to modern living. Some people have actually located well away from the grid in hopes of avoiding the risk. That is probably a little exteme.
How do I know but what I raise my risk considerably by sitting in front of my big screen imac so long each day?
We have smart meters that broadcast 24/7. They do so in every direction. One is located right outsidee my bedroom window. I was a little uncomfortable about it, but we had no options; I didn't make any waves.
When it came time for the water company to add their smart meter, I became a little concerned. We had to sign off on them. So I tell them I'm not real thrilled to have two emitting waves right outside my bedroom window. So I ask what will happen if I refuse? The answer was under their terms of service, I would be given so much time to comply, then my service would be shut off. IOW we have no viable choice. So I signed. They rigged it in a way I don't fully understand; it runs across the basement and is located on another side of the house where they drive by on a different street to read the meter.
I'm 1/2 mile from a cell phone tower. I don't use my microwave any more but not because of that. I play my radio when I am in bed for long hours. I use to sit close to my short wave radio with a tall antenna, and I ran a wire around the top of the room for better reception.
Then there's radon. I decided what will be will be. We are all at risk for something. The numbers for cancer are now 1 in 3 that in an adult's lifetime they will develop one form of cancer.
They don't really know for sure what causes most cancers. Food additives, smoking, pollutants, Roundup is a culprit now, and the beat goes on.
The bottom line is that maybe people should take care at least enough to turn their phones off at night and keep them away from their bodies where practicable, use ear plugs. It won't stop me from becoming a cell phone user if I decide I want one, and I can't see myself doing much texting even if I got proficient at it because the written word does not replace human conversations, and telephone do not replace face to face conversations.
There will undoubtedly be some societal changes in human interaction due to the way we communicate. The majority will rule.
I know one thing for certain. The amount of energy being emitted by your LED iMac is far less than the amount of energy that was once emitted by your big or little screen CRT monitors we used to sit in front of. . . Or the Fluorescent tube backlit LCD screens before the introduction of LED lit LCD screens. In fact, It is probably so small now that you'd be hard pressed to measure it outside of the visible light range.
I long ago decided that the government should pass a regulation requiring that every maternity hospital delivery room post a sign where every new born can see it when he or she can see it when his or her head pops out reading
Give the kid a chance to climb back in right then if he or she doesn't like the possibility that it might be too dangerous to go on out!