If you are talking about irradiated food, then it is safe enough to eat because it probably won’t kill you right away. Any microorganisms that is still living in the irradiated food will be destroyed if microwaved long enough. Because most irradiated food has less nutritional value than non-irradiated food, I suggest staying away from it as much as possible.

The thing that concerns me about irradiated food is that the radiation can change the chemical structure of the food. This is similar to cooking food for too long. When consumed, the body may treat the strange molecules as foreign agents. This may lead to autoimmune and other disorders.