Show me some research backing this up. Are you saying, for example, that a fragment of rope would spontaneously decompose in the absence of air, moisture and light? How long would this take? Show me some research.
If you’re curious dig it up. It’s not likely available on the net, since it was done by a private company (Applied Radiation Co. Later bought out by High Voltage Co.) in about 1960. I was in highschool at the time, but spent considerable time in their lab, and in the cave, after school and on saturdays. Foods sealed in poly wrap and then irradiated would keep for years, still looking fresh, but the same foods just left in the wrap un treated would usually mold out within a few days. I had a deal with them to irradiate our camping rations for our scout troop (it was strictly illegal at the time), so we didn’t need to carry any ice with us.
There is just a huge amount of bacteria and molds on about every suqare inch of the earth, and it works fast.