The Problem with Cedar and Pine Shavings as Pet Bedding and Litter
Cedar and pine shavings are commonly available pet bedding products - but are they harmful to the very animals for which they are intended?
Cedar and pine became popular for pet bedding material because they are good at controlling odor and have some natural insecticidal properties (they kill or repel bugs, especially cedar). These softwood shavings smell nice due to the volatile compounds (e.g. aromatic hydrocarbons, phenols) that are given off. Unfortunately these compounds have been implicated as a potential health risk, especially with regards to respiratory problems (asthma, inflammation, allergic responses) and changes in the liver.
Many of the studies on wood toxicity have actually been conducted on humans, who are exposed to these woods and their by products in the wood product industry (such as those who work in lumber mills who are exposed to lots of wood dust), and these studies often compare the incidence of disease in workers in the wood product industry compared to other workers or the average population.
Studies of laboratory animals have shown fairly dramatic changes in liver enzymes on animals housed on cedar bedding. This in turn can effect the metabolism of drugs including anesthetics, but a direct link between these changes and disease or clinical symptoms hasn't been as clear.
However, based on the studies that implicate the compounds in allergic and respiratory diseases as well as the impact on liver enzymes, it seems prudent to avoid cedar shavings as bedding or litter, especially since alternatives are available.
With pine shavings, the problem isn't quite as clear cut. Pine shavings emit similar volatile compounds but the risks aren't as clear. Many say that drying the shavings releases most of the volatile compounds, so that products such as kiln dried pine are safe. You may still wish to use an alternative bedding or litter completely free of these compounds to be on the safe side.
If you are used to using wood shavings, aspen is a good option that is widely available. There is an increasing number of other litter or pellet type products on the market now, which are appropriate for use as bedding or in litter boxes. The best option depends on the type of animal and what the litter is used for. Some of the harder pellet products might be better used in the litter box of a ferret or rabbit, while the softer types of bedding/litter are good for the smaller pets that need their cage lined. However, even some of the pelleted products can be used as a substrate/bedding for rodents, especially as cage liner with some softer bedding provided as a top layer.
Some of the newer alternative include paper-based pellets (absorbent and hold together so the wet parts can easily be scooped out), litters made from a variety of other organic materials (e.g. cherry/maple wood, aspen wood or bark, grain by-products, wood pulp fibers), and even paper strips (which are soft, but not very absorbent). Another often overlooked alternative is alfalfa pellets (e.g. rabbit food) which are cheap and fairly absorbent. For a compilation of alternatives that are fairly readily available depending where you are see:
References and Recommended Reading
~ Lianne McLeod