Introduction

Types of cat litter

Somewhat surprisingly, there has not been a methodical, scientific, side-by-side comparison test of cat litter in nearly 20 years. In 1990, animal behaviorist Dr. Peter Borchelt compared 14 types of commercial kitty litter as well as topsoil mixed with clay litter and playbox sand -- in three 10-day tests. However, his investigation was aimed at determining which types of litter cats prefer, rather than identifying the best individual brands. Consumer Reports, which shines in so many other product categories, has never conducted a comparative roundup of cat litter.

Fortunately, there's no shortage of cat owners, cat experts and veterinarians who've compared and contrasted various brands and types of cat litter. A review at Gomestic.com compares five different brands of cat litter, while a similar review published on Slate.com covers four cat litter brands, using the author's cat, Izzy, as the guinea pig. We found comparable reviews at The Lighthouse Online and Suite101.com, as well as the San Francisco Chronicle and About.com. Because choosing the proper type of cat litter (clumping clay, biodegradable, crystal, etc.) is so important, we also looked for advice in articles from Petfinder.com and Cats International, in which expert authors discuss (and sometimes debunk) beliefs about various cat litter formulations.

Over the past few years, one major issue has dominated considerations about cat litter -- the advantages of organic, biodegradable cat litters over fine-grained, clumping clay litters. Unlike clay kitty litters, biodegradable cat litter -- which can be made of everything from corn to pine wood to recycled newspapers -- can be flushed down the toilet or used as mulch or compost. Some owners also claim these litters do a better job of controlling odors.

Environmental issues aside, support for biodegradable cat litter rests on two shaky assumptions. First, there has been much Internet chatter in recent years about the feline health effects of sodium bentonite, the chemical in clay litters that causes them to clump (that is, to condense into hard, scoopable lumps on contact with cat urine). Jacque Lynn Schultz, an adviser at the American Society for the Prevention of Cruelty to Animals (ASPCA),  writes in an article posted on Petfinder.com debunking this notion, citing the director of Cornell University's Feline Health Center, who says he has seen no adverse health impact on cats from using clumping clay litters.

Perhaps more importantly, in a 1990 comparative study, Dr. Peter Borchelt reached the conclusion that most cats naturally prefer fine-grained clumping clay litters to other types, at a rate of almost two to one. Interestingly, some types, such as wood chips, corn and recycled paper cat litters weren't preferred at all by cats in the test.

You may want to seriously consider a biodegradable cat litter, especially if your cat (or kitten) hasn't already gotten used to the feel of a clumping clay litter. One of the most recommended brands of cat litter among experts and owners is Feline Pine (*Est. $12 for 20 lbs.) by Nature's Earth, which is made out of pellets of pine. Cats are notorious creatures of habit, so if yours has been using a specific type or brand of litter for years, it will be very difficult to get it to switch. For that reason, owners report better success using biodegradable cat litter with young cats. Smaller, 7-pound bags are also available (*est. $5) for cat owners who are unsure if their cats will successfully transition to a new litter.

In comparative reviews, owners rave about Feline Pine's economy -- one 20-pound bag can last as long as 60 pounds of clay litter -- because you only have to put a small amount in the litter box. Owners also like its fresh scent and eco-friendliness. One added advantage of this organic cat litter is that it's safe for very young kittens (younger than three months), which should not use fine-grained clumping clay litter because they can accidentally ingest the particles. However, Feline Pine has two downsides: First, it doesn't clump, which can make the litter box harder to clean. And second (as mentioned above), many cats simply don't take to its large-grained texture.

For those who use Feline Pine but would also like a biodegradable litter that clumps, Nature's Earth has come out with Feline Pine Scoop (*Est. $12 for 11 lbs.), which is the consistency of saw dust rather than large pellets. Kate Benjamin at ModernCat.net lists it as one of her favorites because it clumps fairly well. She says that her cats like the texture, but that it's not the best in odor control. There are not many user reviews for Feline Pine Scoop, but of those that do exist, most praise its clumping factor and its ability to mask odor. One consumer at Amazon.com complains of it tracking all over the house, but most find that its eco-friendliness outweighs a little sweeping.