Here is some advice from Nam:
Jennifer wrote:
Activated carbon/charcoal also works wonders. It actually absorbs the odor, rather than covering it up (which is what things like Fabreeze does) and it’s a lot more environmentally safe. 🙂
You can get it at any pet store or any superstore that has a pet section. They sell it for fish tanks. Some places also sell it in the garden department.
I put the piece in a freezer bag and pour an amount of the carbon into a dixie cup and leave it for a few days, works very well.