Hello, it’s me: your friendly, neighborhood environmental journalist, here to ruin your day. Or the very least, your lunch.

If you’ve eaten at Sweetgreen, Chipotle, or pretty much any “fast-casual” chain in the past few years, you’ve likely been served your quick workday lunch in a light brown “100 percent compostable” molded fiber bowl. You know the one — the smooth lines of an Apple product, the earthy color of a cage-free farmer’s market egg, the pleasing texture of an organic cotton tunic. It’s the kind of bowl designed to make you feel good even when it comes time to scrape out the dregs of your burrito, one that seems to whisper that it’s okay you didn’t bring your own lunch in a reusable, glass container.

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Well, I’m here to blow some cold reality onto those eco warm and fuzzies. According to a new report from The New Food Economy, those bowls aren’t actually biodegradable. Not only that, they contain cancer-linked “forever chemicals” that likely endanger your health and the environment.

A view of the Shophouse Rice Bowl during Chipotle presents “Cultivate Denver,” a culinary celebration in Denver's City Park on August 17, 2013 in Denver, Colorado.

Jason Bahr / Getty Images

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Unlike styrofoam, wax-lined paper or, Gaia forbid, plastic, molded fiber bowls seemed to offer a guilt-free way to use single-use to-go containers. Both consumers and companies like the idea that we can make a big enough climate difference while not changing our habits one bit. But as has proven to be the case with denim, recycling, and carbon offsets, the idea that “we can have our cake and eat it too” is largely a consumerism myth. And take-out bowls, it seems, are no exception. You probably would have been better off throwing that bowl in the trash (many people do, anyway).

So what’s wrong with molded fiber bowls specifically? The big issue is that they, like many consumer products, contain PFAS, or per- and poly-fluoroalkyl substances. Those are a broad class of manmade chemicals that do not biodegrade naturally — ever. Like, not in ten years, not in 10,000 years.

Best known as the chemical behind Teflon non-stick pans, they can be found in a variety of products, like fire-fighting foam, stain-resistant clothing, and food packaging (Apparently, treatment with PFAS is what made molded fiber bowls so good at holding hot and greasy foodstuffs without falling apart.)

And although several states have moved to ban the stuff in products such as food packaging, PFAS’ long-lasting nature means they’ll likely remain in our water, soil, and bodies for the foreseeable future. So to sum up: Not only do these “compostable” bowls not actually biodegrade, they end up making industrial compost, the water used to process it, and the eventual soil they are meant to replenish, toxic.

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Some companies have been using these bowls to serve their customers for years, giving their corporate environmental responsibility optics a helpful green-haloed boost. (Note: there is no evidence that the restaurants knew about the presence of PFAS in the bowls). And according to The New Economy, the city of San Francisco has already announced plans to completely ban the molded fiber bowl effective January 1, 2020.

In response to the news, Chipotle told Newsweek in a statement: “As evidenced in Chipotle’s Sustainability Report, we are committed to using safe and sustainable food packaging and only partner with suppliers who make fluorochemical sciences and food safety a top priority. These suppliers operate under strict guidelines set forth by the FDA, and have all provided Chipotle with certification that all raw material and finished pulp products fully meet regulatory requirements.”

So, where does this revelation leave us? Are all environmental solutions a lie? Of course not. But experience seems to suggest we be skeptical of inherently consumerist “green” solutions.

After all, there’s no such thing as a carbon-free lunch.