4G Voice vs 3G vs 2G?

On the same phone how much difference is it normally between 4G Voice, 3G and 2G nets radiation wise? Lets say over one minute which one Tech is giving the most hazardous radiation and how much better are the tro other?

I don't know for voice, but 3G txt messages emit less pulses than 4G txt messages.  I think the strength of the signal should be the same, it's just the encoding/pulsing frequencies that are different.  Just try each one and see if there any felt difference.