Compostable...To Be or Not to Be

July 15, 2014

We all know that the banana peel is compostable. But, what about the paper cups I used at the picnic I had over the weekend? Can I put them in my curbside food scrap collection cart?

Serviceware and other products that display the Biodegradable Products Institute’s (BPI) Compostable Logo meet either ASTM D6400 "Specifications for Compostable Plastics" (bioplastics) or ASTM D6868 “Specification for Biodegradable Plastic Coatings on Paper and other Compostable Substrates” (fiber-based applications) standards. ASTM D6400 or D6868 are the only certified standards for compostability. Products certified through ASTM or BPI are intended to compost effectively in large-scale composting operations. Product testing to meet the ASTM standard is overseen by the National Science Foundation in partnership with BPI.

ASTM D6400 covers plastics and products made from plastics that are designed to be composted under aerobic conditions in municipal and industrial aerobic composting facilities, where thermophilic conditions are achieved.

ASTM D6868 covers items that include plastics or polymers where plastic film/sheet or polymers are incorporated (either through lamination, extrusion or mixing) to substrates (such as a paper cup or plate) and the entire item is designed to be composted under aerobic conditions in municipal and industrial composting facilities, where thermophilic temperatures are achieved.

Products that do not say “ASTM” or “BPI” certified will not necessarily compost in a large-scale compost operation. If the product states that it is “compostable,” “biodegradable,” or “decomposable” it may or may not be designed to compost at a large-scale compost operation.

Confused? Understandable!

According to Justin Gast in his June 2014 Resource Recycling article “Label Games,” there are nearly 200 verifications (and corresponding labels) that are being used on products (and services) to denote a sustainability claim.  These “eco labels” can be created via legislation or national programs; or, developed by private entities, non-governmental organizations, public agencies, or jointly by stakeholders and experts. And, as we all know from the use of the “chasing arrows,” its use is designed to denote a product’s “recyclability.” However, in practice the product or packaging on which the arrows are used may in reality have limited or no recyclability due to market or collection barriers.

Similarly, if a product or packaging says its “compostable” or “biodegradable” it may in fact be. However, if it does not have the BPI label on it or ASTM 6400 or 6868 certified it may not be.

According to BPI, “the Compostable Logo is designed to address the confusion that has existed by building credibility and recognition for products that meet the ASTM standards among consumers, composters, regulators and others. It is designed to be easily recognizable and able to be placed on the actual product as well as packaging materials and sales literature.”

However, it’s a voluntary program. Unfortunately, there are lots of products out there that claim to be “compostable,” but have not been certified. And, suppliers often do not know the difference or do not necessarily only promote “compostable” products that are certified.

Why is certification important? Non-degradable plastics—paper plates coated in plastic, plastic straws, noncompostable plastic utensils, etc.—cost the composting industry millions of dollars every year. These contaminants add greatly to processing costs, increase the percentage of material that winds up not being compostable and must be landfilled, and can lower the value of the compost end products if the remaining plastic fragments are found in the compost.

Hopefully, as food scrap composting becomes more mainstream, companies will find more incentive to certify their products. Companies can benefit because the standards provide credible compostable claims for their products in the marketplace.

It is also important for those of us setting up food scrap compost collection programs, zero waste events, and conducting outreach and education on composting, to promote BPI’s certification. This will not only benefit compost operations, but also companies that do get their products certified. And, it will help consumers to more easily know what products they purchase can be composted.

By Athena Lee Bradley