Pine and cedar shavings - It has been found that both cedar and pine shavings are NOT acceptable as bedding for rats, mice, and other pocket pets. They are in fact dangerous! Studies have shown that exposure to the phenols in cedar and pine (the chemical that makes them smell nice) can cause respiratory difficulty, as well as liver and kidney damage. For details on the dangers of cedar and pine bedding, please reference the Cedar and Pine Toxicity article this website's Healthcare tab.
Other wood beddings - what could possibly be more uncomfortable than sleeping on wood? Who wants to be poked by sharp or jagged objects all the time? It would be like people sleeping on a bed of nails. Rats want to be comfortable in their cage. Please explore better options.
Fluffy beddings like Carefresh and similar products - these beddings may be soft, but they can contain live parasites just waiting to move into the fur of your rat. If you plan to use this type of bedding put the unopened bag directly into your freezer and leave it there for 3 days.
Wool and nylon fiber bedding - strands of it can get wrapped around a rat's neck, feet, ankles, paws, etc. cutting off circulation and resulting in amputation of a limb. We speak from experience!
Risks of wood, hay, straw, and fluffy bedding - At Tiny Toes Rat Rescue, we've had so many rats arrive with what seemed to be an eye injury and, upon examination by a veterinarian, it was found that the rat had either wood fragments, hay, straw, or fibers from bedding like Carefresh stuck in their eyes. Can you imagine how painful that is?
Clumping and clay-based kitty litters - they are not suitable as bedding. Clay-based litters are very dusty and can cause problems with the rat's delicate respiratory system. Clumping litters can cause problems if ingested. Rats are very clean animals and they surely don't want to lay in something that is only going to make them dirty like dusty litters will and then have to constantly swallow the residue from them as they try to clean themselves.
Fleece fabric blankets - they are ideal for rat cages and rats love to snuggle in them. Fold several layers over so rats can crawl in between them to stay warm. Blankets will soak up urine so they should be washed in hot water every 2-3 days so the rat has a clean fresh smelling environment. To save money you can buy blankets from thrift stores, but avoid blankets with fringe or anything else that could get wrapped around the rat's neck or be a choking hazard, and wash them first before using. Fabric stores always have sales on fleece so why not just buy several yards of it so you have plenty on hand? It's a great solution.
Clean newspaper - it is a great option in cages for furred rats. Not only do rats love it, but it is absorbent. These days newspapers are printed with non-toxic soy ink so it is safe for rats. Don't bother using the advertisements that are printed on the slick style papers because it is not absorbant. Rats will spend many happy hours shredding the newspaper and making nests. It is what rats love to do! Never use wood or newspaper in a cage for hairless rats because it is rough and will irritate their gentle skin. Instead, use layers of soft fabric like fleece in their cage and make sure they have enough to sleep under to stay warm. Fabric must be laundered every few days or the build up of ammonia and feces will irritate their delicate skin.