We can all guess that kitty litter is bad for the environment, but do you know why?  

Strip mining is required to make clay-based kitty litter.
Litter is most often made with a natural clay called sodium bentonite.  Natural means green, right?  Wrong.  This non-renewable resource is strip mined for the specific purpose of producing cat litter. Strip mining is an extremely destructive process that destroys the land simply to dry out the clay for your cat to defecate in a box. Harmful to the earth and its inhabitants. Plus, kitty litter typically contains silica dust, a known carcinogen. 

Used cat litter sits in landfills for...well, forever. 
Most cat litter is non-biodegradable and it pollutes groundwater. Throwing out used litter in a plastic grocery bag certainly isn't helping the environment either. Some litters are advertised as flushable, but that doesn't mean they're environmentally friendly.  Cats often carry parasites that many water treatment facilities are not equipped to remove.

Eco-friendly litter options (that cost a bit more money). 
Some litter is made from recycled newspaper compressed into pellets. Some products use corn or wheat husk or pine.  These plant-based litters are the byproducts of other industries, which is better than strip mining the Earth to make cat litter.  Remember that biodegradable doesn't necessarily mean that a product is actually breaking down--it may still end up clogging a landfill, especially if you tie the litter in a plastic bag from the grocery store.  Here are biodegradable kitty litter options with the most positive reviews:

Feline Pine: 100% natural pine , available as clumping or original non-clumping. Check out their website to try it free with rebate or download printable coupons.

Purina Yesterday’s News: Not only is the packaging recyclable, these pellets are made from recycled newpaper. Choose from original formula or softer texture pellets.

Swheat Scoop: Natural wheat litter, with multi-cat formula available.

Low-cost alternative: Toilet train your cat!
Cats don't like being told what to do, and telling Kitty to starting using the human toilet is no exception. Toilet training your cat be quite stressful for your cat and for you--trust me, I know.  But making the switch from the litter box to the toilet can help save the environment and even save you money, not to mention no more cleaning a litter box. You can buy a training kit online (try CitiKitty As Seen on TV) or make your own using a metal mixing bowl and a plastic deli tray, which is what I did for my cat in the picture above.  The training kits will tell you that Kitty could be using the toilet in as little as 6 weeks.  Maybe.  But my super clean cat who hates the litter box still hasn't come close to agreeing to balance on the toilet seat, and we've been working on it for almost 2 months now.  But how awesome will that be when I have a cat who uses the toilet?