Because the refill is made from compostable materials, once you have finished using it you can put it in your compost heap (make sure to rinse it and then cut it into pieces to make it biodegrade quicker). By composting the bamboo refill, you contribute to enriching the soil and supporting the growth of new plants!
If you don’t have a compost heap, put your refill in the general waste where it will break down naturally in landfill in less than two years without causing any harm to the environment. That’s faster than a banana peel!