Biodegradability standardization and testing (ISO 17088, EN 13432)

01Overview and value chain

Markers: [EC: EN 13432 / ISO 17088 · ASTM D6400 | OECD: 2.8 Industrial biotechnology | Regulator: EPA (US)]

Biodegradability certification exists to police a word. “Compostable” and “biodegradable” are not interchangeable, and only the former is a defined, testable claim tied to a specified environment and timeframe — which is why certification is third-party and legally consequential rather than a marketing exercise. The European route runs through EN 13432 for industrially compostable packaging; the American route through ASTM D6400 for plastics and ASTM D6868 for coatings, laminates and fibre-based packaging. Behind both sits the same laboratory battery: biodegradation, disintegration, ecotoxicity, heavy metals and, increasingly, fluorine analysis, since a material that fragments but poisons the resulting compost has failed. The distinction that matters commercially is the disposal environment: industrial composting runs hot and managed, whereas home composting does not, and home certification requires full biodegradation in household compost within 180 days. The schemes are also tightening rather than settling — the Seedling scheme’s 2026 revision adds a requirement to demonstrate ultimate biodegradability for each organic constituent in the one-to-fifteen-percent range, closing a gap where minor ingredients previously escaped individual scrutiny.

The key directions of biodegradability certification are:

1. EN 13432 Industrial Compostability: the European conformity route for industrially compostable packaging, operated through certification schemes whose marks are trademarked and licensed rather than self-applied.
2. ASTM D6400 and D6868 Certification: the US route, covering plastics under D6400 and coatings, laminates and fibre-based packaging under D6868, delivered as independent third-party certification with legal weight in end-of-life claims.
3. Home Compostability Certification: the separate and stricter regime for household conditions, requiring complete biodegradation within 180 days without the managed heat of an industrial facility.
4. The Testing Battery: the laboratory work underpinning every label — biodegradation, disintegration, ecotoxicity, heavy metals and fluorine analysis — complemented by field testing that shows how a product behaves under real, regionally variable composting conditions.

Sectoral value chain

[Material Formulation] ──> [Laboratory Testing] ──> [Conformity Assessment] ──> [Mark Licensing]
                                                              │
                                                      (field verification)
                                                              │
                                                              ▼
[Waste Stream Acceptance] <─── [Labelled Product] <───────────┘

Value chain levels

Cross-cutting technologies of the sector:

• Disintegration and Ecotoxicity Testing: the checks that separate genuine compostability from mere fragmentation, ensuring residues neither persist visibly nor harm the compost’s biological quality.
• Field Testing: real-condition observation of how products disintegrate under practical composting, capturing local variability and regional climate that laboratory conditions deliberately exclude.
• Licensed Certification Marks: trademarked labels owned by scheme holders and granted under licence, which is what makes a compostability claim traceable to an assessment rather than to a supplier’s assertion.

02US

The US operates its own standards and a single widely recognised certifying body, and the categorical point it presses is terminological: compostable is a certified claim, biodegradable is not.

ASTM D6400 and D6868, third-party certification, compostable versus biodegradable

• BPI (Biodegradable Products Institute): a product described as BPI compostable has been independently certified to meet ASTM D6400 for plastics or ASTM D6868 for coatings, laminates and fibre-based packaging, indicating that it will fully degrade in industrial composting facilities.
• The terminological distinction: BPI’s own guidance is explicit that “compostable” and “biodegradable” are not interchangeable, and that its certification is a third-party, legally relevant validation of end-of-life performance rather than a descriptive adjective a manufacturer may adopt at will.
• Why third-party status matters: because the claim concerns what happens after the product leaves the seller, it cannot be verified by the buyer at the point of sale — which is precisely the condition under which independent certification, rather than self-declaration, becomes the only workable mechanism.

03CN

China’s approach is standard-dense rather than mark-centred: a layered body of national standards defines degradable plastics, their classification and labelling, and the specific test methods, supplemented by provincial standards for particular product categories.

national degradation standards, defined test methods, provincial product standards

• Definitional and labelling standards: GB/T 20197-2006 sets out the definition, classification, labelling and degradation performance requirements for degradable plastics, providing the terminological base that a claim must sit on, with GB/T 38082-2019 covering biodegradable plastic shopping bags specifically.
• Test methods: the framework specifies distinct methods for distinct questions — GB/T 19277 for aerobic composting biodegradation rate, GB/T 19811-2005 for determining the degree of disintegration of plastic materials under defined pilot-scale composting conditions, and GB/T 22047-2008 for ultimate aerobic biodegradation in soil — alongside photo-biodegradation and thermal-oxidative degradation assessments.
• Provincial layer: local standards address particular product categories, including oxo-biodegradable bags, biodegradable retail packaging bags, starch-based masterbatch and compostable fully-biodegradable shopping and refuse bags, reflecting a system that regulates by product type as well as by test method.

04EU

Europe holds the reference standard, the flagship mark and the testing houses, and the notable 2026 development is that the scheme is tightening its evidence requirements rather than consolidating.

Seedling scheme 2026 revision, OK compost home and industrial, laboratory and field testing

• DIN CERTCO and the Seedling scheme: the Seedling mark is a trademarked certification owned by European Bioplastics since 2012 for industrially compostable products under EN 13432. Its 2026 scheme update, effective 1 January 2026, introduces a requirement to demonstrate ultimate biodegradability for each organic constituent within the one-to-fifteen-percent range — a tightening aimed squarely at minor constituents that aggregate testing could previously carry.
• TÜV AUSTRIA (OK compost HOME and INDUSTRIAL): certification distinguishing the two disposal environments, with the home scheme validating that packaging and eco tableware — bagasse bowls, PLA cups, cornstarch cutlery — fully biodegrade in household compost within 180 days against EN 13432 and ASTM D6400 expectations. TemperPack’s Green Cell Foam is among the products carrying both home and industrial certification.
• Normec OWS (testing laboratory): provides industrial compostability testing for large-volume biowaste streams such as waste bags, coffee capsules and packaging, covering biodegradation, disintegration, ecotoxicity, heavy metals and fluorine analyses. It also runs field testing as a real-world complement, observing disintegration under practical composting conditions with their local and climatic variability, explicitly as an addition to laboratory testing rather than a replacement for it.

05Leading companies and research institutes

06Tech stack and innovations

The stack is a testing regime wrapped in a licensing regime, and its recent movement has been toward closing evidentiary gaps rather than toward new measurement techniques.

1. Standard Conformity Routes:
   • EN 13432 and ISO 17088 anchor the European and international route for industrially compostable products, while ASTM D6400 covers plastics and ASTM D6868 coatings, laminates and fibre-based packaging in the US.
   • The routes are not interchangeable in practice, so a product sold across both markets carries evidence assembled against each, which is a cost driver rather than a technical difficulty.
2. Environment-Specific Certification:
   • Industrial composting is managed and hot; household composting is neither, so home certification is the materially harder claim and is bounded explicitly — full biodegradation in household compost within 180 days.
   • Products therefore carry environment-qualified marks rather than a single compostability status, and a home certification implies the industrial case while the reverse does not hold.
3. The Evidence Battery and Its 2026 Tightening:
   • Certification rests on biodegradation, disintegration, ecotoxicity, heavy metals and fluorine analyses together, because a material that fragments without mineralising, or mineralises while contaminating the compost, fails the purpose of the standard even if it passes one test.
   • The Seedling scheme’s 2026 revision requires ultimate biodegradability to be demonstrated for each organic constituent between one and fifteen percent, removing the shelter that aggregate testing gave to minor ingredients.
4. Field Testing and Real Conditions:
   • Laboratory conditions are deliberately standardised, which makes results comparable but not predictive of any particular facility; field testing observes disintegration under practical composting with its local and climatic variability.
   • The stated position of the testing houses is that field work complements rather than replaces laboratory testing — an honest limit on what either method alone establishes.

07Value chains and production pipelines

Industrial pipeline of a compostability certification (EN 13432, ISO 17088, ASTM D6400 and D6868, GB/T 20197 and GB/T 19277)

┌───────────────────────────┐      ┌───────────────────────────┐
│ 1. Formulation &          │ ───> │ 2. Laboratory Testing     │
│    Constituent Declaration│      │                           │
└───────────────────────────┘      └───────────────────────────┘
                                                  │
                                                  ▼
┌───────────────────────────┐      ┌───────────────────────────┐
│ 4. Conformity Assessment  │ <─── │ 3. Environment Selection  │
└───────────────────────────┘      └───────────────────────────┘
               │
               ▼
┌───────────────────────────┐      ┌───────────────────────────┐
│ 5. Mark Licensing         │ ───> │ 6. Waste Stream           │
│                           │      │    Acceptance             │
└───────────────────────────┘      └───────────────────────────┘

Stage 1: Formulation and Constituent Declaration

The product and its full composition are declared, including minor ingredients. This step gained weight in 2026: a scheme revision now asks for ultimate biodegradability evidence on each organic constituent between one and fifteen percent, so a formulation that relied on aggregate performance must be documented ingredient by ingredient.

Stage 2: Laboratory Testing

The battery is run under the standard’s specified conditions — biodegradation, disintegration, ecotoxicity, heavy metals and fluorine analysis. Passing one and failing another is not a partial result: a material that disintegrates without mineralising, or that leaves the compost toxic, fails the standard’s purpose.

Stage 3: Environment Selection

The claim is bound to a disposal environment. Industrial composting assumes managed, elevated-temperature conditions; the home regime assumes none of that and sets an explicit 180-day full-biodegradation requirement in household compost, which is why the two certifications are separate rather than tiered by convenience.

Stage 4: Conformity Assessment

A certification body evaluates the dossier against EN 13432, ISO 17088 or the ASTM pair and issues a conformity decision. Because the claim concerns behaviour after disposal, this third-party step is the only point at which it can be tested at all — the purchaser cannot verify it.

Stage 5: Mark Licensing

The certified product carries a trademarked mark under licence — the Seedling mark has been owned by European Bioplastics since 2012 — which ties a visible label back to an assessment rather than to a supplier’s wording.

Stage 6: Waste Stream Acceptance

The labelled product meets real composting infrastructure, where regional practice and climate determine what actually happens. Field testing exists precisely to observe this gap between standardised laboratory conditions and practical composting, and it is offered as a complement to certification rather than as evidence in place of it.