It will be discharged out of your body lah.... dont worry so
much...
When I was in the army last time, the out-rations were also served
in styrofoam boxes... and as we have no spoons, we would usually
tear out a small corner of the box and use it as a scoop... and in
the process, we might have accidentally eaten quite a lot of the
styrofoam... hahahaha
But nowadays army out-rations are packed in cardboard boxes
already....