I Tried To Find a Sustainable Litter Bag and It Broke Me

As much as I’m aware that blaming the climate crisis on individual consumer choices is a favorite smokescreen of large corporations and fossil fuel companies, it still totally kills me to buy single-use plastic bags. So when my household recently ran out of the 900 black disposable litter bags we’d bought on Wirecutter’s recommendation eons ago, I decided to be a Good Person and replace them with the most environmentally friendly option I could find. I mean, how hard could it be?

Hoo boy.

What started out as a naïve quest to find the greenest pet waste receptacle has become my Joker origin story. It’s turned me into Mark Ruffalo in Dark Water, except instead of taking on Dupont, I’m hounding companies with names like The Original Poop Bag and Doggy Do Good for the chemical makeup of their “green” bags. I’ve been red-pilled on advanced recycling. And, worst of all, I still haven’t actually bought a replacement — because the entire “green,” “biodegradable,” “plant-based,” “compostable” pet waste bag industry is built on misdirections, half-truths, and outright lies.

This might seem like a ridiculous thing to have spent my time obsessing over (and I don’t entirely disagree with you). But the greenwashing and obfuscation around these bags is part of a bigger story. Plastics are the fossil fuel industry’s last stand. The renewable energy transition, albeit in fits and starts, is here. Seeing the writing on the wall, companies like ExxonMobil, Shell, and Saudi Aramco are heavily investing in petrochemicals, which are used to make plastic and are expected to make up half of oil demand growth between now and 2050, according to the International Energy Agency (IEA). As Armco president and CEO Amin Nasser has reassured his cohorts, oil demand from petrochemicals is expected to remain high “no matter which energy transition scenario plays out.”

But I’m getting ahead of myself.

This story starts with much cuter villains: my cats.

The Case Against “Compostable” Bags

Meet the adorable antiheroes of this story, Marinka and Virginia:

This whole piece is just an excuse to show you a picture of my cats.Jeva Lange/Heatmap

These two cutie pies don’t know it, but they diligently contribute to the 5.1 million tons of feces produced by America’s dogs and cats every year. One estimate of the dog sector alone found that disposing of all that waste adds some 500 million single-use bags to U.S. landfills annually.

The evils of single-use plastic bags have already been drilled into most of our heads by now: They take years to break down and when they do, they don’t decompose but rather turn into tiny microplastics that end up in the soil, waterways, food chain, and even our bloodstreams and breast milk. There is one seemingly great and trendy way to get around this: compostable bags!

Alas, if something sounds too good to be true, it is. For one thing, the “compostable” claims made by eco-friendly pet companies are wildly misleading. Though brands like to imply that their bags decompose and disappear like any other yard waste, these products only break down within a year under the extremely specific conditions of a commercial composting facility — very, very few of which even accept pet waste in the first place. As a result, the FTC has flagged that “compostable claims for these products are generally untrue.”

A "compostable" poop bag available on Chewy.com...Chewy.com

...and why you should always read the fine print.Chewy.com

Companies love to exploit consumers’ lack of knowledge around these terms and processes, though, and are mostly free to do so since the language isn’t strongly regulated. Often brands will brag that their compostable bags meet the “ASTM D6400 standard,” which just means they meet the industrial composting standard — again, pretty useless for us in this context. (Touting the ASTM D6400 standard is also often a way for brands to hide that their bags are made with virgin fossil fuels … more on that soon).

The bigger question when it comes to composting pet waste is, do we even want to? Dogs and cats are meat eaters, which means their poop contains parasites and bacteria like roundworms and hookworms, which can last for years in the soil and even be passed onto humans if used as a fertilizer for edible plants. While maybe this doesn’t sound like it could be that big of a problem, it is: “A study by the Bureau of Sanitation found that 60% of the bacteria in a Marina Del Rey, [California,] waterway was because of animals, domesticated and feral,” the Los Angeles Times reports. Gross.

This is one time you’ll ever hear me say that dog people have it better, though. Done correctly, dog owners actually can home compost dog waste if they’re so inclined. That said, a major downside of compostable bags is that they seem to lead some people to the impression that they can litter trails and parks with their “green” bags since the bags will eventually “go away.” As previously discussed: No, they won’t.

Cat waste, however, never basically should end up in your garden: Felines carry the parasite Toxoplasma gondii, which can be passed onto humans via compost but has been found to kill wildlife, including the sea otters in California. “Toxoplasma infections contribute to the deaths of 8 percent of otters that are found dead, and is the primary cause of death in 3 percent,” The New York Times explains. While feral cats used to be blamed for spreading the parasite, new evidence shows house cats almost certainly are, too — through their waste.

So compostable pet waste bags are out. As one municipality put it, dog and cat poop should be treated like what it is: not a fertilizer, but a pollutant. That means it needs to be sequestered, one way or another, in a landfill.

The Case Against “Flushable” Bags

Just going to nip this one in the bud. For the same reason that composting pet waste isn’t advisable due to parasites and bacteria in four-legged meat-eaters’ feces, flushable pet waste bags and litter aren’t a safe or responsible choice, either.

Many waste treatment facilities don’t kill Toxoplasma, so putting cat poop in the toilet just expedites its journey into your local waterway. Indeed, in responding to an utterly unhinged email I sent them about cat waste, the California Association of Sanitation Agencies confirmed that “the only thing that should be flushed is human waste and toilet paper.”

The Case Against “Biodegradable” or “Plant-Based” Bags

Biodegradable pet waste bags are what radicalized me.

At first glance, these bags appear to be the best option. A number of them come on the recommendation of the sustainability website Treehugger. The product websites usually feature blogs full of reassuring information about how harmful plastic waste is, or boast 1% for the Planet certifications, or mention something about being made of cornstarch. Even the bags are green!

And almost all of them, despite their lofty claims, are made using virgin fossil fuels.

Polybutylene Adipate Terephthalate, or “PBAT,” is a biodegradable plastic made from the petrochemicals butanediol, purified terephthalic acid (PTA), and adipic acid. Translation: Fossil fuels must be extracted in order to make any bag that contains PBAT, which is virtually all of them.

Companies are exceptionally sneaky about this, though. Some of the brands boast outright about using PBAT as a traditional plastic alternative, likely assuming customers have no idea what the acronym means and won’t bother looking it up. Yet as Alice Judge, a former veterinarian and co-founder of the U.K.-based sustainable pet website Pet Impact, found in her own investigation, PBAT rarely makes up less than 60% of these supposedly “plant-based” pet waste bags. “There is some really concerning greenwashing and outright lying” going on in the industry, she told me. “We’ve found brands that are very big, reputable brands even saying explicitly ‘100% plant-based’ and in the same sentence saying ‘made from cornstarch and PBAT.’”

"Zero plastic" — but contains a fossil fuel-derived chemical called PBAT.Sirwaggingtons.com

PBAT is typically combined with cornstarch or sugarcane, so a “plant-based” bag advertising those ingredients can often be a tip-off that a fossil fuel product is also involved. Additionally, companies will frequently flag on their packaging that they meet the ASTM D6400 or BPI standards, though these have no provisions against certifying biodegradable products that contain PBAT.

Pet waste bag companies appear to go out of their way to avoid these admissions. Doggy Do Good, a popular sustainable pet waste company, told me in an email they use a “proprietary bio-based material” for “60.9% of the composition of their bags” — that is, the expected amount of PBAT — and added that “this fully biodegradable copolymer is an excellent alternative to polyethylene.” When I pressed to clarify if their proprietary “biodegradable copolymer” in question was PBAT, as I suspected, they stopped replying to my emails. The Original Poop Bag, another green bag company, didn’t answer me at all when I asked if their bags contained the fossil fuel product.

Despite these avoidance tactics, biodegradable bag companies aren’t using PBAT because they nefariously want to ruin the planet. It’s just the dirty secret of the pet waste bag business. As Judge explained in a blog post, “All poo bags have to include PBAT for strength and structure. If they were 100% plant-based, they would turn to mush very quickly when wet, lack strength, and tear easily (some qualities you really don’t want in a poo bag!).”

Fair enough. It’s the lack of transparency that is the problem: Most of these companies are selling fossil fuel-based products to customers who think they’re buying bags made from corn.

What's the other 62%?Doggydogood.com

Ultimately, there are two ways to think about the impact of the pet waste bags you buy: the impact of the materials used to make them and the impact of their disposal. If the latter is your biggest concern — what happens to bags after they’ve been used — biodegradable and “plant-based” bags are still probably the best, if imperfect, option available on the market. You can throw them in the trash (where they belong because again, pet poop is a pollutant) but also know at least that they’ll eventually biodegrade in a landfill (it should be noted, though, that everything is technically biodegradable, and the word means nothing without specification about the timeline and conditions).

From an “input” perspective — what the bags are made of, and how — biodegradable and “plant-based” bags are a little less exciting. They require less virgin fossil fuel than buying a bag entirely made out of traditional single-use plastic, though some research has suggested there is “no real difference in lifetime emissions between” products made with traditional plastic and those made from bioplastics. By another estimate, greenhouse gas emissions “are typically higher for bio-based plastics than recycled and virgin plastics” because “corn requires large amounts of energy, space, and water to grow industrially” and “turning the corn starch (once cultivated) into a polymer requires considerable energy.”

There is one major exception to all of this: Avoid “oxo-biodegradable” products. These are banned in the EU because they break down, sure — but into toxic microplastics.

The Case Against “Recycled Plastic” Bags

Though they’re comparatively rare, you can find “recycled plastic” pet waste bags on the market. They apparently cut down on virgin fossil fuels by recycling plastic that’s already been extracted. (Judge’s company, Pet Impact, sells its own poo bag made from recycled ocean plastic, oyster shell waste, and “about 25 to 30%” virgin fossil fuels).

Even 100% recycled materials have their problems.

But while recycled plastic sounds great, it has — you guessed it — its own complications.

“Chemical” or “advanced” plastic recycling is the current sweetheart of the oil and gas industry, despite evidence that recycling plastic isn’t nearly as good as it’s chalked up to be. For one thing, the process of converting old plastics into new plastics is incredibly emissions-intensive and thus requires the burning of fossil fuels to generate the required energy. The recycling process can also spew cancer-causing chemicals into the air that disproportionately poison low-income communities of color, like those in “Cancer Alley.”

This is a problem that stretches far beyond the humble poo bags: Hundreds of companies now sell everything from clothes to shoes to shampoo bottles on the boast that they’re made from recycled plastics. Yet “by feigning ‘recycling’ (really, downcycling) of plastic pollution, companies can divert attention from their role in perpetuating this crisis while pulling in profits,” stresses the advocacy group Plastic Pollution Coalition. Recycled plastic can be just another smokescreen when what’s really needed is a reduction of single-use plastics altogether.

The Case Against Buying Any Bags At All

But it was reducing single-use plastics that got me into this whole mess in the first place.

In March 2020, a month when nothing else of note was happening, New York City banned single-use carryout plastic bags, joining San Francisco and a number of other towns around the country. But like many pet owners, grocery store plastic bags had been our go-to litter scooping bags. As we became more conscious of single-use plastics in some parts of our lives, it led us to buy … a bunch of single-use plastics to use for our pets.

As the pandemic wore on, my husband and I eventually decided to fly across the country with Marinka and Virginia in order to be with our families. There, my stepmother introduced us to a revolutionary new poop bag. It didn’t require the extraction of any new fossil fuels, and while it doesn’t break down in a landfill, it also won’t poison any otters.

The name of this holy grail of poop bags? Trash.

Empty bread bags can become the perfect chutes for scoops of litter. Plastic packaging gets a second life as a final resting place for kitty unmentionables. Bags of dry cat food, once exhausted, can be refilled.

This isn’t a perfect solution, either (for example, “produce bags aren’t engineered to be particularly durable, nor to hold in liquids or odors,” Wirecutter warns with the confidence of experience). But if I’ve learned anything in this mad, scatological journey, it’s that there is no perfect solution. What satisfies one person’s environmental concerns — about greenhouse gas emissions, fossil fuel extraction, or waste and pollution — might not satisfy someone else’s. And at a certain point, you have to make a choice, and likely a compromise, and then move on to focusing on the things that make a bigger difference, like what you drive, where you get your power from, or what you eat.

All this is to say, the trash method works for me because it makes single-use plastics destined for the landfill anyway into twice-use plastics. And at least it allows me not to think about cat poop anymore.

I think I’ve done enough of that to last me a lifetime.