Compostable Packaging Certification (EN 13432 / ASTM D6400): A Mandatory Requirement for LeXiang Products Entering European and American Markets

In October 2024, a client running a new tea beverage brand flew back from the United States. The first thing he did after landing was call me:

"My PLA cups are clearly compostable, so why did the buyer at Whole Foods say we can't place them in their eco-friendly section?"

He sent me a screenshot of the email from Whole Foods, which stated: "Compostable products must be certified to ASTM D6400 or TÜV OK Compost. Your products do not have certification."

This client had spent two years promoting "100% biodegradable eco-friendly cups" in China, only to discover in the U.S. that "biodegradable" and "compostable" are not the same thing at all — Whole Foods requires third-party certification, not the biodegradable properties of the material itself.

What he didn't know was: starting in 2024 in the EU and from 2027 in California, USA, packaging labeled as "compostable" is subject to mandatory third-party certification requirements. The two main global compostable certification standards — Europe's EN 13432 and North America's ASTM D6400 — have already become hard thresholds for products to be placed on the shelves of European and American retailers.

This article clarifies the core differences between the EN 13432 and ASTM D6400 standards, their mutual recognition status, and uses three real material cases (PLA, PBAT, and paper-plastic composite) to explain which materials can pass, which cannot, and why.

EN 13432 and ASTM D6400 are two independent but highly similar standards

First, let's review the background and core requirements of both standards.

EN 13432 (European Union, published in 1994, updated in 2000): Full title "Requirements for Packaging Recoverable through Composting and Biodegradation - Test Scheme and Acceptance Criteria." Issued by the European Committee for Standardization (CEN), it is the supporting standard for the EU "Packaging Directive 94/62/EC." Any packaging sold in the EU labeled "compostable" must comply with EN 13432 or an equivalent standard. Certification bodies include TÜV Austria (OK Compost mark), TÜV SÜD, DIN CERTCO, and others.

ASTM D6400 (North America, published in 1999, updated in 2019): Full title "Standard Test Method for Determining Aerobic Biodegradation of Plastic Materials in Soil or Compost Under Controlled Conditions Found in Municipal Solid Waste Composting Facilities." Issued by the American Society for Testing and Materials (ASTM), it forms the basis for BPI (Biodegradable Products Institute) certification. Any "compostable" packaging sold in North America must comply with ASTM D6400 or an equivalent standard (such as BPI certification).

The core provisions of both standards are nearly identical, divided into 4 mandatory test criteria:

• Biodegradation rate — In an industrial composting environment (58°C ± 2°C constant temperature, specific humidity, specific microbial community), more than 90% of the material must be broken down into CO2 and water within 90 days
• Compost quality — After composting decomposition, the quality of the compost product must not be affected (indicators such as heavy metals, toxicity, and pH)
• Ecotoxicity — Plants grown in the decomposed compost must not be affected in their growth (typically measured using pea or oat germination rates)
• Heavy metal content — Heavy metals such as Pb, Cd, Hg, Cr, Cu, Ni, and Zn must be below the limits set by the EU 94/62/EC Packaging Directive

The core differences between the two standards mainly lie in the details:

• EN 13432 test temperature is 58°C ± 2°C; ASTM D6400 is also 58°C ± 2°C (the same)
• EN 13432 maximum test duration is 6 months; ASTM D6400 is also 6 months (the same)
• The ecotoxicity test is mandatory under EN 13432, and it is also mandatory under ASTM D6400 (the same)
• Heavy metal limits in EN 13432 reference the 94/62/EC limits; ASTM D6400 references US EPA limits (figures differ slightly)

Mutual recognition: The EU TÜV OK Compost certification and the North American BPI certification have a mutual recognition agreement. Passing TÜV OK Compost generally means passing BPI, and vice versa. However, the Chinese national standard GB/T 19277 is not fully mutually recognized with these two standards, and reports issued by domestic certification bodies may not be accepted overseas.

Case Study 1: Why PLA Cups Pass EN 13432

Back to the PLA cup from the new tea beverage customer mentioned at the beginning. PLA (polylactic acid) is a bio-based plastic derived from corn starch or sugarcane, which can achieve 90% decomposition within 90 days under industrial composting conditions.

Can his PLA cup pass EN 13432? It depends on two parts:

• The PLA material itself can pass EN 13432—mainstream PLA suppliers such as NatureWorks and Synbra all hold TÜV OK Compost certification. Pure PLA material can achieve a biodegradation rate of 95%+ within 90 days.
• However, whether the "entire cup" can pass depends on the combination of cup body + ink + film coating + adhesive—if any component is non-compliant, the entire cup will fail.

His specific situation at the time: the PLA cup body material was OK, the printing ink was standard oil-based ink (without environmental certification), and the cup lid PLA coating contained PBAT compound. When the entire cup was sent to TÜV for testing, heavy metal Cr residue from the ink after composting decomposition was 0.05%, exceeding the EU limit of 0.025%. The result—the entire cup failed.

The customer's issue was not that PLA material was unsuitable, but that the ink and coating were not matched. He later switched to water-based ink + single PLA coating, and within 3 months resubmitted for testing and obtained the OK Compost certificate. The conclusion of this story: PLA material itself is compostable, but for the entire cup to pass certification, all materials in the set must be compliant simultaneously.

Case 2: Why Many PBAT Composite Films Fail Certification

In 2023, a customer producing e-commerce courier bags pursued compostability certification targeting the EU market. The courier bags were made of PBAT+PLA composite film (PBAT is a copolymer of poly(butylene adipate-co-terephthalate), commonly used in biodegradable plastics).

TÜV test results submitted: 90-day biodegradation rate was 78%, below the 90% threshold. Failed.

Reason: PBAT degrades more slowly than PLA under industrial composting conditions. When the PBAT proportion in the composite film exceeds 30%, the overall degradation rate is slowed down. The customer subsequently reduced the PBAT proportion from 40% to 15%, then resubmitted for testing, achieving a degradation rate of 92% and passing certification.

Lesson from this case: Compostability certification cannot rely on a material merely "claiming to be compostable"; the biodegradation rate must be actually tested under industrial composting conditions. Different formulations yield dramatically different results. The customer spent 120,000 RMB on the first submission (materials + testing fees), then another 60,000 RMB on the second (material adjustment + retesting), and finally obtained the certificate.

Case Study 3: Why Paper-Plastic Composite Packaging Cannot Be Labeled "Compostable"

In 2024, a client making takeaway food containers wanted to pursue compostable certification. The containers used a kraft paper + PLA coating structure, and the marketing copy read "100% Compostable."

After reviewing the product, we advised them not to submit it for testing. The reason: when the PLA coating thickness in a paper-plastic composite structure exceeds 30μm, the entire cup can only degrade 50-60% within 90 days under industrial composting conditions. To meet the 90% threshold, the PLA coating thickness must be controlled below 15μm, but coatings below 15μm do not provide sufficient barrier performance, and takeaway containers would leak oil.

The client ultimately chose between two options:

• Option A: Label as "Compostable," reduce PLA coating to 15μm, but only suitable for dry food (not suitable for takeaway soups and liquids)
• Option B: Label as "Recyclable" (if local paper recycling systems exist), retain the 30μm coating

The essence of this case is the trade-off between "performance vs. sustainability." The client cannot have it both ways. This is the biggest pitfall of compostable certification—many brand owners assume "paper + coating = compostable," but in reality this is not the case.

Summary of Real-World Performance of the 3 Material Categories

The following is a summary of these 3 case categories presented as a material performance table, intended as a reference for factories seeking compostable certification:

PLA (Polylactic Acid):

• Achieves 90%+ biodegradation within 90 days under industrial composting; compliant with EN 13432 / ASTM D6400
• Price is 50-80% higher than ordinary plastics
• Note: Heat resistance is limited to within 50°C; not suitable for hot beverages or microwave use
• Note: Inks, adhesives, and laminated layers must also be compliant for the entire cup to pass certification

PBAT (Polybutylene Adipate/Terephthalate):

• Degrades slowly when used alone; meets standards when blended with PLA
• Price is 30-50% higher than ordinary plastics
• Note: A PBAT content exceeding 30% will slow down overall degradation
• Note: Actual lab testing is required; it is not acceptable to infer compliance based on the theoretical compostability of "composite materials"

Paper-Plastic Composite (Kraft Paper + PLA Coating):

• A coating thickness below 15μm can pass certification, but barrier performance is insufficient
• A coating thickness above 30μm cannot pass certification
• Practical application: For packaging dry foods, Option A can be applied; for packaging foods containing water or oil, it is recommended to pursue "recyclable" or "ordinary plastic" pathways

There is another concept frequently confused by customers: home composting and industrial composting. EN 13432 / ASTM D6400 tests industrial composting conditions (58°C constant temperature, controlled humidity, and specific microbial communities), whereas home composting conditions are far milder (25-40°C). Even after passing EN 13432, placing the product in a home compost bin will very likely show no visible change after several months — consumer complaints such as "the compostable cup I bought didn't change after I put it in my compost bin" are typically attributed to this reason.

Certification Cycle, Costs, and Validity

The actual cost of compostable certification falls into three categories:

Testing fees: TÜV Austria OK Compost testing fees are 80,000–150,000 (depending on product complexity); BPI testing fees are 60,000–100,000 (North America). Running both certifications for the same product totals approximately 200,000.

Cycle time: From sample submission to certificate issuance takes 6–12 months (6 months of testing + report review + certificate issuance). This is the biggest hidden cost of certification—time.

Validity period: OK Compost certificates are valid for 5 years, with re-testing required upon expiration. BPI follows a similar approach. However, any change in formulation requires re-submission (even if the ink supplier is switched).

Does China have a compostable certification? Yes. The Chinese national standard GB/T 19277.1-2003 equivalently adopts EN 13432. However, GB/T standards are not mandatory certifications, and reports issued by domestic certification bodies may not be recognized overseas. For export orders, it is recommended to obtain TÜV OK Compost or BPI certification directly.

Decision Table for Compostable Certification

If you are a brand owner or factory, ask these 3 questions before making a "compostable" decision:

Question 1: Does the target market truly require "compostable"? EU retailers (such as Whole Foods, Alnatura) mandate it, California in the U.S. will require it starting 2027, and other regions do not currently mandate it. If the target market is only domestic, there is no need to pursue EN 13432; GB/T 19277 will suffice.

Question 2: Can the product formulation be "fully eco-friendly"? Any single non-compliant item will compromise the entire cup. It is recommended to conduct a "formulation compliance assessment" before sending samples for testing—verify that every material (substrate, ink, lamination, adhesive) is sourced from suppliers holding TÜV OK Compost or BPI certification.

Question 3: Can the budget support 6–12 months? Compostable certification is a long-cycle project, with a budget of 150,000–250,000 (including testing fees, material adjustment fees, and design revision fees). Small-batch orders may not be able to amortize the costs, so it is recommended to proceed only when order volumes exceed 1 million units.

Once these 3 questions are answered clearly, then decide whether to pursue compostable certification. In 2024, LeXiang provided compostable certification consulting for 4 clients—ultimately 2 actually launched projects, 1 revised the approach to "recyclable," and 1 abandoned certification and reverted to conventional plastic. Thinking it through before making the decision saves 50% in costs compared to remediation after certification.

Further Reading

Related Articles:

• Soil Burial Tests of Biodegradable Materials vs. Real-World Performance Gaps
• The Practical Value of Eco-Friendly Packaging for Brands
• What International Certifications Are Required for Exporting Packaging Materials
• Compliance Guide for Packaging Recycling Symbols