What's the Greenest Way to Dispose of Cat Litter?

greener ways to dispose of cat litter illustration

Treehugger / Ellen Lindner

There are multiple green and eco-friendly ways to dispose of cat litter, each with its own advantages and disadvantages. Because of the wide variety of cat litters, the different wastewater treatment and sewer systems in each municipality, and the difficulty in composting cat waste, there isn’t one solution that will work for everyone.

You’ll first need to research what kind of litter will work best for you and your fluffy friend. Litter these days is made out of a wide range of materials, from potentially toxic to all-natural materials. You’ll then have to decide how you want to dispose of the litter. (Flushing it down your toilet is not a safe or responsible option.)

Cat waste is different from dog waste. If not properly disposed of, cat waste has the potential to be hazardous to you and the environment. Being a green pet owner isn’t always easy, but it’s important to be aware of every option before you purchase cat litter in order to make the most sustainable decision. 

Biodegradable Litter

person studies cat litter bag ingredients hovering over a cat litter box

Treehugger / Lesly Junieth

Choose a kitty litter made of natural materials that break down and return to the earth. Look for ingredients such as recycled compressed paper, wood shavings, corn, grass seed, pine, wheat, and sawdust. Most biodegradable cat litter is made of various plant-based products and can be more expensive than grocery store litter. Keep in mind that many of those mainstream cat litters contain silica dust, which has been found to cause upper respiratory infections in humans. Also, avoid litters that contain sodium bentonite (clay) or fragrances. These materials are harmful to both cats and the environment due to their extraction methods and use of chemicals.  

Biodegradable Bags

tattooed hand carries brown paper bag with cat waste past litter box

Treehugger / Lesly Junieth

The easiest and most common method to dispose of cat waste is to scoop it out of the box, tightly seal it in a bag, and toss it in the trash. A biodegradable bag designed for cat litter may seem like a great option. However, these kinds of bags, allegedly designed to compost more quickly, have very mixed results. 

If you must contain the waste in a bag before you add it to your trash bin, opt to use a brown paper bag. These take less time to break down than a plastic bag or even current biodegradable bags on the market. 

Studies and FTC Ruling

Biodegradable bags seem like a great idea, but unfortunately, they don’t always perform as they should. In a 2019 study conducted by the University of Plymouth, researchers took five kinds of plastic bags and exposed them to air, buried them in the ground, and submerged them in the sea for three years. Three years later, the biodegradable, oxo-biodegradable, and conventional plastic formulations were still strong enough to carry groceries after being in the soil or the marine environment. This raises a lot of questions about whether these biodegradable bags can actually deteriorate enough to make them a viable substitute for standard trash bags.

According to a press release put out by the Federal Trade Commission (FTC) in 2015, manufacturers and marketers of dog waste bags were told that “their ‘biodegradable,’ ‘compostable,’ and other environmental claims may be deceptive.” Do your due diligence before buying compostable bags. You can look up ASTM International standards to figure out the level to which plastics are biodegradable — make sure the poop bags you purchase meet their strictest criteria.

Why You Shouldn’t Flush Cat Litter

cat studies toilet while sitting on gray rug in bathroom

Treehugger / Lesly Junieth

Flushing cat litter and waste down the toilet is risky and potentially harmful to the environment. For starters, cat waste can clog your pipes, contaminate drinking water, and hurt ecosystems. Even if it’s advertised as “flushable litter,” it might not be safe for your pipe system. Some litters aren’t designed for septic systems, let alone the fact that many septic systems can’t break down certain materials like cat waste, no matter what litter you use.


Cat waste can contain the parasite Toxoplasma gondii, which can cause toxoplasmosis—a disease that is especially dangerous for pregnant women and anyone with a weakened immune system. Because T. gondii can be spread in water and soil, flushing cat litter or cat poop creates a risk of infection. Always dispose of cat waste in safer ways.

How to Safely Compost Cat Litter

gray and white kitty sits on outdoor balcony net to fiddle leaf fig plant

Treehugger / Lesly Junieth

Some cat people claim composting cat poop is possible, but this can also be dangerous to humans because cat feces can contain T. gondii. If you plan on using compost on or near any edible gardens, avoid using any pet waste. Compost made of pet waste is to be used only on lawns or non-edible crops (like a rose garden or perennials).

You can build your own pet compost if you have the room in your backyard, and don’t mind dealing with some really stinky materials. Keep in mind it will require plenty of precaution and patience. Ideally, pet waste compost should sit at least one year before use, as it will need plenty of time and heat to kill any nasty pathogens.

If you’re still interested in taking this route, contact a local composting expert. You’ll want to get expert advice in your area on whether or not to do it and how to do it safely. Never put anything from your cat’s litter box into your municipal yard waste or curbside composting container. It will cause everything in the container to be thrown in the garbage, defeating the whole purpose of composting. 

Cat Diet and Sustainable Litter Boxes

kitty walks past a stainless steel litter box and pauses to look back

Treehugger / Lesly Junieth

What goes in, must come out. If your cat is eating highly processed foods with little nutrients and lots of preservatives, Fluffy’s fecal matter will also have few nutrients and contain a lot of preservatives. This is problematic for the environment because the fewer naturally derived ingredients a substance has, the less it will break down. As with most trash in the U.S., waste that sits in already overflowing landfills means higher methane emissions, which means more greenhouse gases in our air. It’s a good idea to feed your cat food that is as natural as can be. The same rules for nutritious human foods can be followed with your pets: Always strive for food as close to its natural state as possible, with an emphasis on sustainable meat or plant-based options whenever feasible. 

Most cat litter boxes are made from plastic, which is a fossil fuel byproduct that Treehugger highly discourages purchasing brand new. Consider upcycling a plastic tub that would otherwise get tossed in the trash, or pick one up at your local thrift store. If you want to make an investment in a long-lasting option that won’t absorb odors, consider a (used) stainless steel steam pan. 

While it’s true that our pets’ environmental footprint is bigger than we’d like to think, researching every option and making informed purchasing decisions will help you and your Fluffy live a more sustainable life.

View Article Sources
  1. "Toxoplasmosis: General FAQs." Centers for Disease Control and Prevention.

  2. "Health Effects of Particulate Matter and Silica Exposure." University of Wisconsin Eau-Claire.

  3. Napper, Imogen E., and Thompson, Richard C. "Environmental Deterioration of Biodegradable, Oxo-Biodegradable, Compostable, and Plastic Carrier Bags in the Sea, Soil, and Open-Air Over a 3-Year Period." Environmental Science and Technology, vol. 53, no. 9, 2019, pp. 4775-4783. doi:10.1021/acs.est.8b06984

  4. "Composting Dog Waste." United States Department of Agriculture.