What "Compostable" on a Dog Waste Bag Actually Means

What the FTC says the word has to mean

The rule is section 260.7 of the FTC’s Green Guides, Compostable Claims. A marketer claiming an item is compostable “should have competent and reliable scientific evidence that all the materials in the item will break down into, or otherwise become part of, usable compost” in “an appropriate composting facility, or in a home compost pile or device,” and do so “in a safe and timely manner.”

Two qualifications follow, and both bear on a poop bag. The claim should be clearly and prominently qualified if “the item cannot be composted safely or in a timely manner in a home compost pile or device.” And it should be qualified “if such facilities are not available to a substantial majority of consumers or communities where the item is sold.” The Guides’ own example is a lawn and leaf bag marked “compostable” that only municipal yard trimmings programs can process. Where those programs aren’t available to most buyers, the bare word is deceptive, and the marketer should say something like “Appropriate facilities may not exist in your area.”

So the word on the bag is a claim about the material. The two qualifications are about where the bag can actually go, and that is the part a shopper has to supply.

Is “biodegradable” the same claim?

No, and the Guides hold it to a harder test. Section 260.8, Degradable claims, says an unqualified degradable or biodegradable claim needs evidence that “the entire item will completely break down and return to nature” within “a reasonably short period of time after customary disposal.” Then it names the case a dog walker is in. “Unqualified degradable claims for items that are customarily disposed in landfills, incinerators, and recycling facilities are deceptive because these locations do not present conditions in which complete decomposition will occur within one year.”

The section’s first example is a trash bag. A marketer advertises it as degradable on the strength of soil burial tests, but consumers put trash bags into the solid waste stream, which ends in a landfill or an incinerator, so the claim is deceptive. A bagged dog waste that goes into a public trash can is on the same path. The same section extends its rule to “oxo-degradable” and “oxo-biodegradable” claims by name.

What a backyard pile can and can’t take

EPA’s page on composting at home keeps a list titled “What to Avoid Adding to a Backyard Compost Pile.” Two entries matter here. “Compostable foodservice ware and compostable bags” is one, marked with a footnote: “Backyard composting piles generally do not reach high enough temperatures to fully decompose these materials. These materials can be composted at commercial composting facilities. Check first to make sure your specific facility accepts them.” The other entry is “Pet waste and cat litter,” listed without qualification.

That is the whole problem in two lines. The bag is a material a home pile isn’t hot enough for, by EPA’s account, and what’s inside it is on the same page’s avoid list on its own.

What the certification mark covers

Most compostable bags sold in the US carry the mark of the Biodegradable Products Institute. BPI’s own certification page explains that it offers two tiers. “Commercial Only Certification certifies that items will break down in commercial compost facilities, while Commercial & Home Certification certifies that items will break down in both commercial compost facilities and in properly managed home compost bins.” The two are tested differently. Commercial certification runs disintegration testing “at 58 +/-2° C for up to 84 days”; home certification runs it “at 25 +/-2° C for up to 180 days.”

Then there is a line written for exactly this product. “Pet waste products are limited to Commercial Only Certification for use in Canada since backyard bins don’t typically get hot enough to kill the pathogens in pet waste.” That is BPI’s statement of its own eligibility rule and its own reasoning. It describes Canada; the page states no equivalent rule for the US, and this post doesn’t infer one.

What a bag maker says about where the bag ends up

Earth Rated, whose bags are made from recycled plastic rather than compostable material, publishes a comparison of the two on its own site, PCR vs. biodegradable poop bags. Its summary of its own compostable line is blunt. “Compostable bags only work as advertised if your municipality accepts pet waste at an industrial composting facility. Most don’t.” A companion post on how and where to compost dog poop states that “industrial composting of pet waste is not widely available in the USA.” Both are the manufacturer’s statements about its own market, and a company that sells recycled plastic bags has a reason to make them. They line up with the regulator and the certifier above, which is why they’re here.

What to read on the package

Three things, in this order. Whether the word is “compostable” or “biodegradable,” because the first is a claim about a facility and the second is a claim the Guides treat as deceptive for anything headed to the trash. Whether a certification mark appears and which tier it names, because commercial and home certification are tested at different temperatures and mean different things. And whether the package says where the bag can go, because the FTC’s rule is that a compostable claim should be qualified when most buyers don’t have a facility to use, and the bag’s own qualification is the manufacturer telling you so.

None of that is a verdict on compostable bags. Where a municipal program takes bagged pet waste, the bag can do what its label says. Where none does, the bag goes where every other bag goes, and the FTC’s degradable rule describes what happens there.

Where this comes from

Every regulatory statement above is quoted from the FTC’s Green Guides at 16 CFR 260.7 and 260.8, linked in the text. The backyard composting statements are quoted from EPA’s own page, and the certification statements from BPI’s own certification page, both linked. The manufacturer statements are quoted from Earth Rated’s own site, also linked. Runlow has not tested any waste bag and makes no claim about any brand beyond what that brand states on its own site.