If you preserve food scraps for composting, a liner bag marked as compostable or biodegradable may seem like a perfect way to transport all those vegetable peels and coffee grounds to your compost heap or municipal collection bin while keeping your kitchen bucket clean. However, whether or not you should purchase those liners depends on a number of variables, and experts advise avoiding liners altogether or using paper bags that have already been used.
What you need to know about compost bin liners, why they could be counterproductive even though they can be composted, and how to keep your kitchen organized without them are provided below.
Table of Contents
What are compostable bags?
Compostable bags resemble petroleum-based plastic produce bags in appearance and feel, but they are made of plant-based substances such vegetable starches, wood pulp, lactic acid, or soy proteins. These substances are made to be ingested by microbes, which aid in their breakdown into compost, an organic compound that resembles soil.
The issue is that not all composting techniques provide the ideal conditions for these bags to decompose completely. Home composting arrangements typically lack the heat, moisture, and airflow necessary for complete decomposition, while municipal or professional composting facilities do. However, the capabilities of these facilities can vary, so it’s possible that biodegradable bags won’t be allowed even if your food scraps are collected for off-site composting.
Can I put compostable bags in food waste bin?
It varies. The ability of one composting system to accept compostable bags—or even non-compostable ones—may differ from another, just as every town seems to have its own set of regulations on the types of recycling it accepts. For instance, the New York City Department of Sanitation actually permits residents to throw food scraps into collection bins using regular, old, earth-polluting plastic grocery bags, which are later filtered out, in order to increase participation in its relaunched food-waste pickup program in Queens. The most crucial thing you can do is find out what products are and aren’t permitted from your municipal collection, compost drop-off, or private composting service, and then abide by that.
Your best chance if you can use compostable bags is to look for ones with the Biodegradable Products Institute’s emblem. This non-profit group certifies products for compostability, and its certification is widely regarded as the industry standard in the US. (You may also look up a product’s BPI certification here.) In order to verify whether a product would decompose “quickly, thoroughly, and safely, when composted in well-run municipal and commercial facilities,” the certification partly depends on ASTM International compostability requirements. Additionally, it forbids the use of per- and polyfluorinated substances (PFAS), which are occasionally used in packaging and have a relatively long half-life in the environment.