I used to test medical devices, and one if the techniques they use to sterilize things is to expose them to high levels of gamma ray radiation.

...unbelievably high.  As in:  would wipe out small towns if divided up equally.  We had to do testing to verify that the radiation hadn't damaged the plastic too much.

Rod Basler - COFIT (Crotchety Old Fart In Training)

>On Sun, Jun 17, 2018 at 06:44:03PM -0400, Kurt Feltenberger wrote:
>> 1. Wouldn't the radiation have killed the bacteria that would cause
>> decomposition?
>
>Probably not. Although some bacteria are no more radiation resistant
>than our body's cells, a single-celled organism doesn't need the
>support provided by billions of other functioning cells to survive.