Compostable Packaging: What It Is, How It Works, and What Certifications to Require

Compostable packaging has emerged as a critical solution in the transition toward a circular economy for plastics. Yet confusion persists about what “compostable” actually means, how it differs from “biodegradable” or “biobased,” and which certifications provide genuine assurance that packaging will break down as claimed.

Compostable packaging refers to materials designed to completely break down into water, carbon dioxide, and biomass under specific composting conditions, leaving no toxic residues. The key distinction from merely “biodegradable” materials is that compostability requires defined conditions — temperature, humidity, microbial activity, and timeframe — and must meet specific standards that verify complete disintegration and absence of ecotoxicity.

The mechanism of composting involves microbial action that breaks down polymer chains into simpler molecules. In industrial composting facilities, temperatures reach 55-60°C with controlled humidity and aeration, enabling rapid breakdown within 90-180 days. Home composting operates at lower temperatures (20-30°C) and requires longer timeframes, making it more challenging for many packaging materials.

Critical certifications provide the verification framework. The European standard EN 13432 and its international equivalent ISO 17088 define the requirements for packaging recoverable through composting and biodegradation. These standards mandate four criteria: material composition disclosure, biodegradation (≥90% CO2 evolution within 180 days), disintegration (≤10% residue >2mm after 12 weeks), and ecotoxicity testing (no negative effects on plant growth).

In North America, ASTM D6400 provides the parallel standard for plastics designed to be aerobically composted in municipal or industrial facilities. The U.S. Composting Council’s “Compostable” logo and the Biodegradable Products Institute (BPI) certification mark signal compliance with ASTM D6400.

For home composting, the OK Compost HOME certification from TÜV Austria validates materials that break down under the lower temperatures and less controlled conditions of backyard compost bins — a stricter requirement that fewer materials meet.

The “Seedling” logo (DIN CERTCO / TÜV Austria) and the “OK Compost INDUSTRIAL” mark are the most widely recognized European certification marks. In the US, the BPI certification mark is the gold standard. Any compostable packaging claim without third-party certification should be treated with skepticism.

For businesses specifying compostable packaging, the key questions are: Which certification does the material hold? Is it certified for industrial composting, home composting, or both? Does the certification cover the specific packaging format (film, rigid container, coating)? Does the local waste management infrastructure actually accept compostable packaging?

The distinction between compostable and recyclable is also critical. Compostable packaging is designed for organic recycling (composting), not mechanical recycling. If compostable plastics enter the recycling stream, they can contaminate conventional plastic recycling. Clear labeling and consumer education are essential.

As extended producer responsibility (EPR) schemes expand and single-use plastic bans proliferate, compostable packaging offers a compliant alternative for applications where reuse or recycling are impractical — particularly food-contact applications contaminated with organic residues. But its environmental benefit is realized only when it actually reaches a composting facility. Infrastructure, collection, and consumer behavior must align with the material’s design.

Sources:

1. Bioelements, “Packaging compostable: qué es, cómo funciona y qué certificaciones exigir,” July 2026. https://www.bioelementsla.com/post/packaging-compostable
2. European Bioplastics, “Standards and Certifications.” https://www.european-bioplastics.org/standards/
3. Biodegradable Products Institute, “Certification Program.” https://bpiworld.org/
4. TÜV Austria, “OK Compost Certification.” https://www.tuv-at.at/certification/ok-compost/