Electromagnetic fields - EMF, cellphones emit them, are potentially harmful to humans. Virtually all scientists agree that more research is necessary to determine safe or dangerous levels. http://ewg.org.
It's like one big human experiment which we won't know the results of for several decades. There is increased risk of some brain tumors in long term cell phone users.
What we do know is that iron, which is necessary for healthy blood and is stored in the brain, is highly affected by EMFs. The permeability of the cell membranes of nerves, blood vessels, skin and other organs is also affected, as well as the intricate DNA of the chromosomes. Every bodily biochemical process involves precisely choreographed movement of EMF sensitive atoms, molecules, and ions..
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