Cat waste should not be composted, but always scooped from the litter box and put in your trash. BioBag cat litter pan liners are made from corn instead of polyethylene. They "breathe", which allows heat and moisture to escape or evaporate, reducing bacterial build-up of collected waste and the resulting odor. BioBags will decompose in a controlled composting environment in 10-45 days, leaving no harmful residue behind.Each liner is approximately 31.1" x 15.3" and 1.12" thick.