Biodegradable vs. Compostable – What Do They Mean & Which Is Better?
With the increased access to recycling facilities, Americans can be more conscious of sustainability than ever before. You, or people you know, me even go as far as composting food waste in your backyard. For banana peels, grass clippings, and melon rinds, the process is easy.
What about that produce bag you brought home from the store with a “Biodegradable” label? You just finished some leftovers from last night in a container that is labelled, “Compostable in Industrial Facilities.” What do you do with these? Are they the same thing? And when it comes to biodegradable vs. compostable, which is better?
Biodegradable vs. Compostable
To the untrained reader, these two concepts seem almost indistinguishable. The terms “biodegradable” and “compostable” both leave the impression that you’re helping the earth and eliminating your ecological footprint. However, there are some scientific and legal differences that set these concepts apart.
What Does Biodegradable Mean?
As a product marketing identifier, biodegradable indicates that a material will fully degrade within one year of “customary disposal.” This degradation period is in accordance with §260.8(c) of the FTA Green Guides. The Federal Trade Commission considers it deceptive to claim that something is biodegradable without, “competent and reliable scientific evidence that the entire item will completely break down and return to nature.”
According to the EPA, biodegradable plastics include some type of natural polymer that help it degrade into smaller components, “when exposed to the appropriate environment.”
The American Society for Testing and Materials created ASTM D5338 as a standard to measure the aerobic biodegradation under controlled conditions for plastic materials. Further, they created ASTM D6691 as a marine biodegradability measure.
In the United States, the ASTM defines that “biodegradable” standards, and the FTC enforces claims made in the context of those standards.
Does Biodegradable Mean Compostable?
Biodegradable does not always mean compostable.
While compostable materials are always biodegradable, the opposite cannot be said. There are different forms of biodegradation, like marine biodegradation, that make biodegradability a larger class. Compostable materials are a subset of biodegradable materials.
A compostable material is that which meets ASTM D6400, according to the EPA. For example, compostable plastic is plastic that biodegrades into “soil conditioning material” under the conditions of a commercial/industrial composting facility. The composting process uses heat, humidity, and microorganisms to break materials down into water, carbon dioxide, biomass, and other inorganic materials that are like the bulk of the final compost around it.
ASTM Standards D6400 and D6868 lay out the standards that a material must meet to be considered commercially compostable.
What Does Compostable in Industrial Facilities Mean?
When the EPA or ASTM talk about “compostable,” they’re generally talking about commercial composting (also called industrial composting). This means that for a specified product to compost, it needs to find its way to an industrial-scale composting center in your locale.
There are no major legal standards that outline when a product is compostable at home.
Can You Compost Biodegradable Plastic?
In most present-day situations, you can compost biodegradable plastic. The EPA asserts that biodegradable plastic is designed to biodegrade in soil or water. As long as your plastic product isn’t labeled as only marine biodegradable, then it is suitable for composting in an industrial facility.
Is Compostable the Same as Recyclable?
While a compostable and recyclable product both offer a way to optimize earth’s resources, there are some differences. A recyclable material generally has no timeline associated with it, while the FTC makes it clear that biodegradable and compostable products are on the clock once introduced into the “appropriate environment.”
There are plenty of recyclable products that are not compostable. These materials will not “return to nature,” over time, but will instead appear in another packing item or good.
Compostable vs. Biodegradable
So, biodegradable materials are outlined by the ASTM and claims thereof are enforced by the FTC. Compostable items are also outlined by the ASTM, but only include items that are compostable in a commercial composting facility.
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Contact us today for more information about Kaneka PHBH™ for your upcoming production.
