I was called out to a job yesterday where a rat had set up home in a less than year old Mitsubishi Outlander and eaten through most of the wiring loom whilst peeing everywhere. The smell and the mess was astonishing. The damn thing had even left droppings between the headlining and the roof. Composts heaps are fairly common places for rats to make a nest at this time of year, cars thankfully less so.
I wouldn’t be using that compost for food now that you’ve been flinging poison in. Truth be told it probably wouldn’t be very good for much mixed with that stuff.
The active ingredients in rat bait are never present in a concentration of more that 0.005% in most cases and only have an active life of a few weeks inside bodily tissues and vital organs. The presence of a decomposing rat in the compost would be more of a concern.