Similar to the discussion of Greenwashing about a different plastic bag, here’s a discussion about another sample, this time an allegedly biodegradable bag that is quite horrid. There are better biodegradable bags, but this is not one of them. Do not encourage its use, and always read claims with a cupful of salt.
This handled, plastic bag sample is light green, like many compostable bags. But just read carefully what it says about itself:
THANK YOU [for what?]
This bag is our commitment to the environment. [and I worry very much what kind of commitment that is – deceptive or just misled?]
Reusable, recyclable & biodegradable. [NO!!! If it is biodegradable, which it is not, then BY DEFINITION that makes it not recyclable. Putting such bags into plastic bag recycling wrecks the plastic bag recycling. Putting into a curbside collection container wrecks even more.]
Reduces landfill volume [our trash did not go to a landfill, except the ash after waste-to-energy plant has burned it (See discussion under Greenwashing 1); and “volume”?? Compared to what?]
Helps the environment [how??]
Thank you [again] We appreciate your business. [OK, maybe that’s clarifying for what they are thanking us.]
[the not terribly fine print] 49.28% biodegradation in 900 days under Non-typical conditions. No evidence of further biodegradation. ASTMD5511.
Wow. That last one needs its own paragraph. Or 6. Lets start at the end and go backwards. “ASTM International, formerly known as American Society for Testing and Materials, is an international standards organization that develops and publishes voluntary consensus technical standards for a wide range of materials, products, systems, and services.” (why write when I can just copy Wikipedia?)
D5511, and yes I looked this one up, here is to test for how much biodegradation of plastics there will be under conditions of “high-solids anaerobic digestion”. In other words, they are not trying to mimic lifespan in air (litter), in water (litter), in an anaerobic digester (probably more liquids and not “high-solids”), or in your home compost bin (should not go anaerobic), or in a commercial compost facility (ditto). They are trying to approximate conditions in a landfill, so they are presuming that you are throwing it “away” and that’s where it’s going. And even then, it concludes that it doesn’t really prove anything that’s not in a laboratory. And what do they mean by “biodegrade” – turns solid carbon into gaseous carbon. Gee. I thought we were trying to REDUCE carbon going into the atmosphere. Though it, again, totally depends on compared to what.
So what did they find? Even in a landfill only about half of whatever this bag is, decomposes. That’s not “biodegradable”. I still don’t know what this bag is made of, but most likely, it is a beast I had thought/hoped was disappearing that is half plastic and half starch, creating a monster I call “bio-disintegratable”, meaning half biodegrades, and the other half becomes micro- or nano-plastics. Sound good? Yuck!
And return to the setting. Even if a landfill mimicked the testing lab, it took 900 days. You can bet that if ANY biodegradation happened in a litter environment, A) it would take longer, and B) I don’t want to look at it that long, nor deal with the byproducts.
AND a landfill is NOT SUPPOSED TO BE A GIANT COMPOST PILE. The entire point of a landfill, even if we had them around here, which we do not, is to be a giant tomb. They are designed to reduce as much air (yes, anaerobic) and water, so that things stay inert. Decomposing means converting to a combination of leachate (water pollution, whether surface or ground water) and smell or other gasses (air pollution and greenhouse gases). We don’t want things in landfills to decompose. Over enough time, most will anyway, but we want to minimize that, not encourage it.
So then what do they mean by “non-typical conditions”? Darned if I know. Probably they mean laboratory high solids anaerobic. But it’s just possible they mean anything other than the conditions under which it was tested. In any case, their technical claim is that under “perfect” conditions, less than half will biodegrade. And the rest never will.