Dear EarthTalk: What kinds of cat litters are kinder to the environment: traditional clay litters (so-called clumping litters) or other varieties? What about some of the new alternatives, such as those made out of wheat and corn?
—Stef Gandolfi, Oakland, CA
Traditional clay-based clumping cat litters are the most common and widely sold in supermarkets and pet supply stores. Clay litters do not biodegrade and instead pile up in landfills, producing chemicals that can potentially harm human health. According to the International Agency for Research on Cancer, clay litters also produce dusts that contain silicon particles, which are known human carcinogens. In addition, the clay used for litter is obtained through strip-mining, a practice that causing adverse environmental effects on surrounding soil, water and air.
Some pet owners have reported respiratory and other health problems in their cats due to both the inhalation and ingestion of clumping clay litters. Once inside the lungs or digestive tracts, the litter can expand from moisture and cause irritation and blockages. In the lungs this can lead to infection, and in the intestines dehydration and a decrease in nutrient absorption can result. Scientific studies and documented cases of such incidents seem to be in short supply, however, and such claims seem to only be anecdotal.
To be safe, however, there are a number of environmentally friendly alternatives that are deemed safer for people and cats alike. Recycled newspaper, for one, can be used to create cat litter in pellet form. It is biodegradable, flushable, burnable and 99 percent dust-free. It also has the advantage of not getting tracked around the house, unlike clay litters. Fibre Cycle, a company with the primary mission of finding innovative and environmentally friendly uses for recycled paper, sells such paper-based cat litter and claims it to be highly absorbent, biodegradable, long-lasting, lightweight, and virtually dust-free. Plant-based litters are made from materials such as corn, corncobs, cornhusks, wheat byproducts, wheat grass, and beet pulp.
According to Worldwise, a leading manufacturer of environmentally responsible pet products, plain ground corncobs are a good choice because they are made of natural, flushable biodegradable materials, have no odor, are very absorbent, and don’t produce the same kind or volume of dust as clay litters. Litters made from pine and cedar saw dusts offer yet another clay-based alternative. As with the plant-based offerings, they are made from natural scrap materials that biodegrade. They also eliminate odor naturally — because of the innate ability of both pine and cedar to absorb and neutralize ammonia — rather than cover up odors with chemicals and perfumes.
Feline Pine, from Florida-based Nature’s Earth Products, is a wood litter made from 100 percent natural pine that has been heated and pressurized to remove any harmful wood oils. When ready for changing, the biodegradable litter — available in both clumping and pellet varieties — can simply be emptied into the backyard compost or mulching pile. One caution about pine, though: Some cats have a sensitivity to pine aroma and as a result could shun the litterbox altogether.