I recently read in a book by a trusted author that most all of the damage done by radiation was in to form of its interaction with water therby forming radicals that then proceded to do the damage. Is this "in general" true and other books that attribute different actions with different forms of radiation were oversimplifing the details? One memorable example was a microbiology text book that associated UV radiation with small chincks and dimmers in a chromosome, while stateing that gamma radiation was far more dangerouse as it split the DNA completely in to two pieces making the damage nearly unrepairable unless the cell was lucky enough to have a repair molecule working at that spot at that time. Aparently (and logicly) after a few seconds the ends of the DNA hit by gama radiation would be so far apart there would be no way to reconnect them. However after some reflection the idea that radation does damage directly is a bit silly. Tons of water in a cell, far more likely to hit that imho. Well thanks for reading this, maybe someone with some physics knowledge can speak authoritatively on this because id really like to know.