I had to scroll for a while to get past the politics or explanations of how the radiation is produced. Here's the only explanation I could find of what "harmful" entails:
> Many biologists and electromagnetic field scientists believe the modulation of wireless devices makes the energy more biologically active, which interferes with our cellular mechanisms, opening up calcium channels, for example, and allowing calcium to flow into the cell and into the mitochondria within the cell, interfering with our natural cellular processes and leading to the creation of stress proteins and free radicals and, possibly, DNA damage. And, in other cases, it may lead to cell death.
> Many biologists and electromagnetic field scientists believe the modulation of wireless devices makes the energy more biologically active, which interferes with our cellular mechanisms, opening up calcium channels, for example, and allowing calcium to flow into the cell and into the mitochondria within the cell, interfering with our natural cellular processes and leading to the creation of stress proteins and free radicals and, possibly, DNA damage. And, in other cases, it may lead to cell death.