Bio-content certification and mass-balance traceability (ISCC PLUS, USDA BioPreferred)

01Overview and value chain

Markers: [EC: ISCC PLUS / ESPR digital product passport (Reg. (EU) 2026/1778) | OECD: 2.8 Industrial biotechnology | Regulator: EPA (US)]

A bio-based claim is unusual among product claims because the molecule usually cannot be distinguished from its fossil equivalent once made. Two different mechanisms therefore exist to make the claim provable, and they answer different questions. Mass balance is an accounting method: renewable or recycled feedstock is fed into an existing integrated plant, and a certified chain of custody attributes that quantity to specific output products, so a manufacturer can substitute fossil input without reformulating a product or rebuilding a plant. Radiocarbon measurement is a physical test: ASTM D6866 determines biobased carbon content as a fraction of total organic carbon by accelerator mass spectrometry, and it measures what is actually in the sample rather than what the bookkeeping says. The two are complementary — mass balance can certify a product whose molecules are genuinely fossil, while radiocarbon cannot see an accounting attribution at all. Around both, 2026 added a third layer: the EU adopted its digital product passport registry by Commission Implementing Regulation (EU) 2026/1778 on 17 July 2026, covering all product categories in scope of the ecodesign regulation, so that sustainability attributes must travel with the product as data. China moved in parallel, with national standard GB/T 46256—2025 on biobased content and traceability labelling taking effect on 1 March 2026.

The key directions of bio-content certification are:

1. Mass-Balance Chain of Custody: certified attribution of renewable or recycled feedstock to specific outputs of an integrated plant, allowing fossil substitution without reformulation — the method behind biomass-balanced and certified-circular product lines.
2. Radiocarbon Biobased Carbon Testing: ASTM D6866 measurement of biobased carbon as a fraction of total organic carbon, performed by accelerator mass spectrometry, giving a physical measurement independent of any accounting claim.
3. ISCC PLUS Certification and Its Register: voluntary, globally applicable sustainability certification for products from alternative bio-based and recycled feedstocks, with a public register of certificates carrying explicit statuses — valid, suspended, expired, terminated, withdrawn.
4. Digital Product Passports: the EU registry adopted in July 2026 across ecodesign-covered categories, requiring sustainability data to accompany products, with battery passports facing a February 2027 deadline.

Sectoral value chain

[Alternative Feedstock] ──> [Integrated Production] ──> [Mass-Balance Attribution] ──> [Certification]
                                                                    │
                                                          (radiocarbon verification)
                                                                    │
                                                                    ▼
[Market Claim] <─── [Digital Product Passport] <────────────────────┘

Value chain levels

Cross-cutting technologies of the sector:

• Accelerator Mass Spectrometry: the analytical basis of biobased carbon measurement, distinguishing biogenic from fossil carbon by radiocarbon content rather than by chemical structure.
• Public Certificate Registers: searchable records of issued certificates with explicit lifecycle status, without which a certificate claim cannot be independently checked by a customer.
• Selective Data Disclosure: passport architectures that share verified attributes along a supply chain while withholding commercially sensitive detail, the practical condition for participation.

02US

The US contribution is measurement rather than scheme governance: the analytical method that decides how much biobased carbon a product actually contains, and which underpins claims made under domestic procurement labelling.

ASTM D6866 radiocarbon testing, accelerator mass spectrometry, total organic carbon basis

• Beta Analytic (biobased carbon measurement): provides ASTM D6866 testing for biobased and biogenic carbon content, using Method B by accelerator mass spectrometry. The measurement is expressed as a fraction of total organic carbon for biobased products and natural ingredients, which is the basis on which a percentage claim can be stated.
• Why the physical test matters alongside accounting: radiocarbon distinguishes biogenic from fossil carbon in the sample itself, so it verifies what a product contains rather than what has been attributed to it — a check that mass-balance certification by construction cannot provide.
• Procurement context: biobased content percentages of this kind are the currency of federal biobased procurement labelling, which is why the analytical method rather than the scheme is the American anchor of this category.

03CN

China has moved from scattered claims to a national standard, issued in 2025 and effective in 2026, that fixes both how biobased content is determined and how it must be labelled and traced.

GB/T 46256—2025 national standard, traceability labelling, industrial policy backing

• The standard: GB/T 46256—2025, “Biobased materials and products — Biobased content and traceability labelling requirements”, was issued on 29 August 2025 and takes effect on 1 March 2026, published by the State Administration for Market Regulation and the national standardisation administration.
• Who wrote it: the standard was proposed by and falls under the national technical committee for biobased materials and degradable products (TC380), with drafting contributions from Beijing Technology and Business University, Tsinghua University, Sichuan University and a range of domestic producers including Anhui Fengyuan, Zhejiang Hisun Biomaterials and Ningbo Homelink.
• Why now: commentary accompanying the standard notes that global biobased materials capacity has passed 35 million tonnes and that China’s industry is at the transition from research to industrial-scale application, where the absence of product standards, testing and evaluation methods and traceability labelling systems had become the constraint — following a January 2023 joint policy from the industry, development, finance, environment, agriculture and market-regulation ministries.

04EU

Europe supplies the scheme, the certification bodies and now the legal architecture for carrying claims as data, with the largest chemical producers using mass balance to decarbonise existing plants.

ISCC PLUS scheme and register, mass-balanced production at scale, digital product passport regulation

• ISCC PLUS: a voluntary, globally applicable sustainability certification for products and materials derived from alternative bio-based and recycled feedstocks, certifying sustainability characteristics across the supply chain. Its public register lists all certificates and statements of conformity issued by certification bodies, searchable with statuses including valid, suspended, expired, terminated and withdrawn — the mechanism by which a claim can be checked rather than trusted.
• BASF and SABIC (mass balance in production): BASF obtained ISCC PLUS certification and completed REDcert2 recertification at its Lemförde site for thermoplastics and polyurethane systems, using a mass-balance approach to replace fossil resources with renewable and recycled raw materials, and expanded its certified biomass-balanced portfolio with three architectural-coating additives — Dispex AA 4145 MB, Rheovis PU 1333 MB and Rheovis HS 1169 MB — that cut product carbon footprint without reformulation. SABIC’s TRUCIRCLE certified-circular products use advanced pyrolysis of difficult-to-recycle plastics into oil refined back into polymer feedstock with virgin-like properties, alongside recycled-content compounds shown at PIAE 2026 at 30% and 45% post-consumer recyclate.
• TÜV NORD and Circularise (audit and data layers): TÜV NORD CERT, based in Essen, has received provisional authorisation from the German Federal Environment Agency to certify renewable fuels of non-biological origin against the ISCC EU standard, covering green hydrogen and its derivatives, since under the renewable energy directive only certified production and supply chains earn greenhouse-gas reduction recognition. Circularise works on the data layer, where the EU digital product passport registry was adopted by Commission Implementing Regulation (EU) 2026/1778 published on 17 July 2026 across ecodesign-covered categories, and where its collaboration with Honda Motor Europe targets battery-passport readiness before the February 2027 deadline while avoiding disclosure of sensitive information.

05Leading companies and research institutes

06Tech stack and innovations

The stack answers one question in three incompatible ways — by accounting, by measurement and by data architecture — and a serious claim usually needs more than one of them.

1. Mass Balance as an Accounting Method:
   • Renewable or recycled feedstock enters an existing integrated plant alongside fossil input, and certified chain-of-custody rules attribute the renewable quantity to nominated outputs, which is what allows substitution without reformulating products or building dedicated lines.
   • The commercial consequence is visible in product design: biomass-balanced additives are offered as drop-in replacements that reduce product carbon footprint without any change to formulation, so the customer’s qualification work is unaffected.
2. Radiocarbon Measurement as a Physical Check:
   • ASTM D6866 by accelerator mass spectrometry determines biobased carbon as a fraction of total organic carbon, distinguishing biogenic from fossil carbon in the sample itself.
   • The two approaches are not interchangeable: a mass-balanced product may contain no biogenic carbon at all, and radiocarbon testing cannot detect an accounting attribution — which is precisely why both persist.
3. Scheme Governance and Registers:
   • ISCC PLUS certifies sustainability characteristics of alternative feedstocks across the supply chain on a voluntary, globally applicable basis, and the same scheme is the reference for regulated fuel claims, where only certified chains earn greenhouse-gas reduction recognition under the renewable energy directive.
   • A public register with explicit certificate statuses is what converts a certificate from an assertion into something checkable; suspended and withdrawn are the statuses that matter to a buyer.
4. Digital Product Passports:
   • The EU registry adopted by implementing regulation in July 2026 spans all ecodesign-covered categories, moving sustainability attributes from documents into structured data that travels with the product.
   • The practical design problem is disclosure: passports must convey verified attributes along a chain while withholding commercially sensitive detail, which is the condition on which suppliers will participate at all.

07Value chains and production pipelines

Industrial pipeline of a certified bio-content claim (ISCC PLUS chain of custody, ASTM D6866, ESPR digital product passport, GB/T 46256—2025)

┌───────────────────────────┐      ┌───────────────────────────┐
│ 1. Feedstock Sourcing     │ ───> │ 2. Integrated Production  │
└───────────────────────────┘      └───────────────────────────┘
                                                  │
                                                  ▼
┌───────────────────────────┐      ┌───────────────────────────┐
│ 4. Physical Verification  │ <─── │ 3. Mass-Balance           │
│                           │      │    Attribution            │
└───────────────────────────┘      └───────────────────────────┘
               │
               ▼
┌───────────────────────────┐      ┌───────────────────────────┐
│ 5. Certification &        │ ───> │ 6. Passport & Market      │
│    Register Entry         │      │    Claim                  │
└───────────────────────────┘      └───────────────────────────┘

Stage 1: Feedstock Sourcing

Bio-based or recycled input is procured with sustainability evidence attached, whether biomass or pyrolysis oil derived from difficult-to-recycle plastics. The credibility of everything downstream rests here, because a chain of custody can only be as sound as the origin claim it starts from.

Stage 2: Integrated Production

The alternative feedstock enters an existing plant alongside fossil input rather than a dedicated line. This is the economic point of the whole approach: it decarbonises installed assets without rebuilding them, and the output is physically indistinguishable from conventional product.

Stage 3: Mass-Balance Attribution

Certified bookkeeping assigns the renewable quantity to nominated output products under audited rules. This is where the claim is actually created, and it is why the scheme’s audit and register infrastructure matters more than any property of the molecule.

Stage 4: Physical Verification

Radiocarbon analysis measures the biogenic fraction of total organic carbon in a real sample by accelerator mass spectrometry. It answers a different question from the attribution and will not corroborate it — a mass-balanced product can legitimately test as fossil, which is a limitation to state rather than to obscure.

Stage 5: Certification and Register Entry

A certification body audits the chain of custody and issues a certificate, published in a searchable register with an explicit status. For regulated fuel claims the same certification determines whether greenhouse-gas reductions are recognised at all, and authorisation of the certifying body itself may be provisional.

Stage 6: Passport and Market Claim

Attributes are carried forward as structured data under the EU digital product passport regime adopted in July 2026, or under the Chinese traceability labelling standard effective March 2026. Batteries face a February 2027 deadline, and the workable architecture is selective disclosure — verified attributes shared, commercial detail withheld.