Which cat litter is the most environmentally friendly? (column)

Eartha Steward
Special to the Daily
dustpan on cat litter
Getty Images/iStockphoto | iStockphoto

Dear Eartha,

My cat prefers to do his business outside but now that the ground is covered in snow he has to use his litter box. Recently, I went to buy new litter and was confounded by all the different types. Which litter is the most environmentally friendly?

— Sly, Frisco

Sly, that is an excellent question! Did you know that before World War II indoor cats were given a box of sand or ashes to use? If you hate how much litter ends up around your home (I find it in my sheets — bad kitty!), imagine how much worse it would have been back then! The idea to use clay came from an ex-sailor named Ed Lowe. He knew about the absorbent qualities of clay from his father’s firm, which used it to clean up industrial spills in wartime factories. It caught on and now close to 2 million tons of clay are used yearly here in America for absorption of pet waste.

Where does all that clay come from? It is mined, and all mining operations have an environmental impact. Mining the active ingredient necessary for clumping litter, sodium bentonite, is only economical when the material is close to the surface, so the environmental impact is similar to strip mining.

Yes, laws mandate reclamation for this type of mining. However, there are disputes over the extent and timing of those efforts and whether the environmental impacts can ever be fully addressed through reclamation. Regardless, it takes millions of years for new mineral deposits to form in the Earth, so clay is a nonrenewable resource.

As Mr. Steward points out, however, we rely on a lot of things that come from strip mining: some baby powders, aluminum foil and all our electronic devices that we love so dearly just to name a few.

What is an environmentally sensitive cat owner to do? Thankfully there are lots of options. Let’s briefly look at some pros and cons:

Silica Gel-Based Litter

This litter is made from silica dioxide, which is sand found in quartz, and is then mixed with oxygen and water to make silica gel. Quartz is also a nonrenewable resource with mining impacts on the environment making it a non-environmentally friendly option. Yet, it lasts longer so you don’t need as much, which is good news when you think about litter sitting in a landfill and never decomposing.

Plant-Based Litter

There are many companies experimenting with all sorts of eco-friendly materials for cat litter, including recycled newspaper, corn cobs, wheat, pine sawdust and wood chips. There are considerations for how those crops are grown that may make them less than eco-friendly, but overall they have a less harmful impact than non-renewable clay. If you plan on composting the litter after it has been used be sure to remove the feces and only use the compost on non-edible plants.

Compost Mix

Here at the Eartha household we are working to re-create the outdoor environment that our kitty loves by combining our own compost and pine litter from a local store — an environmentally friendly and affordable combination. The jury is still out as we experiment with different proportions but I am hopeful we’ll find a mix that kitty likes.

Toilet Training

From an environmental standpoint this is arguably better than the alternatives. However, from the cat’s point of view, it could be seen as stressful and confusing. Cats have a natural instinct to dig and cover, which a toilet doesn’t allow. And, as our furry friends age, straddling a toilet may not be such a good idea.

This brings me to my final point: Which cat litter to buy isn’t up to us. It’s up to our very smart, very picky feline companions. If our cute kitties don’t like the smell, feel and texture of the litter, they will take their business elsewhere. Case in point, in 1990 Dr. Peter Borchelt ran tests to determine litter preference using commercial products ranging from clay-based litters to plant-based litters. In test after test, fine-grain, clay-based clumping litter was used more than twice as often as its nearest competitor. Interestingly the litter boxes with wood chips, grain litter and recycled paper litter weren’t touched.

Sly, my advice to you is to decide what combination of pros and cons you prefer, present your cat with options, and live with kitty’s choice. It’s worth the effort because as Charles Dickens wrote, “What greater gift than the love of a cat.”

Ask Eartha Steward is written by the staff at the High Country Conservation Center, a nonprofit organization dedicated to waste reduction and resource conservation. Submit questions to Eartha at

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