It starts with 100% pure kiln dried pine that is then processed into pellets. These premium pellets are sterile and free from any bacteria or pathogens. They are free of silica dust and will not stick to the fur or feet of your cat so you will not have any messy tracks throughout your home .Environmentally Friendly, Feline Fresh premium pine pellets are made from 100% pure pine, non-toxic and completely safe for all pets and people, even if ingested. When you change your litter box you can dispose of the used litter (solid waste removed) into your compost pile or use it as mulch in the garden. Planet Wise Products utilizes 100% pine that is a natural by-product of the lumber industry.