If you know who Blight from Batman Beyond is, similar to that. Basically, he would be able to emit radiation both generally, and in concentrated waves and beams. However, this causes his skin to progressively fall off as he uses it, until he is nothing but a glowing skeleton. He would be able to regrow skin lost in this manner over time though. He would also be able to absorb concentrated amounts of radiation, with the opposite effect of causing tumors on his skin which eventually will fall off. I also have no problem with the populace despising him because of this.