How dangerous are alpha, beta and gamma radiation?

Alpha radiation can be very dangerous because it is strongly ionising but can be easily stopped by dead cells on the skin’s surface. But if alpha emitters are inhaled from contaminated dust or swallowed from contaminated food, they can be extremely dangerous. When swallowed or inhaled the alpha particles cash into living cells and damage their DNA. While Beta particles are less dangerous because they are less ionising but can easily penetrate into the body and damage cells. Because gamma radiation is weekly ionising and therefore less dangerous, it can penetrate into the body but is likely to pass straight through.