oSIST prEN 18348:2026

• Abstract:

  The work item aims to differentiate between biodegradable and non-biodegradable plastic materials. Non-biodegradable plastics are defined as those plastics which do not biodegrade, even in conditions which are conducive to the process. In contrast, the biodegradation of biodegradable plastics occurs when they come into contact with active microorganisms, under conditions that are conducive to biodegradation. This process is analogous to the biodegradation of natural polymers. The plastic materials that are categorised as being intrinsically biodegradable can be utilised in the design of products with a high risk of dispersion. The test scheme is not intended to be applicable to any specific application. Instead, the objective is to develop a framework methodology that can be utilised across diverse industrial sectors for the identification of biodegradable plastics, with the subsequent application of these plastics in the manufacture of various products and for different purposes. The work item does not intend to characterise and evaluate the environmental impact of products containing plastics identified as biodegradable. The test scheme should address the definition of intrinsic biodegradability of plastic materials, without determining the hazard potential of the products, which necessitates a distinct assessment that extends beyond the scope of this particular work item. The rate of biodegradation of a plastic object is not the focus of this particular work item, as it is contingent on environmental conditions. The test scheme to be developed will not be sufficient to carry out an analysis of the ecological risk associated with the dispersal of products, as this requires an assessment of the intrinsic hazard, of the environmental fate, in addition to the assessment of biodegradability.

• Status: Not Published
• Public Enquiry End Date: 30-Jul-2026
• ICS: 83.080.01 - Plastics in general
• Technical Committee: IPMA - Polimer materials and products
• Current Stage: 4020 - Public enquire (PE) (Adopted Project)
• Start Date: 27-May-2026
• Due Date: 14-Oct-2026
• Completion Date: 03-Aug-2026
• Ref Project: prEN 18348 - Plastics — Intrinsic biodegradability — Criteria and test methods

oSIST prEN 18348:2026 is the Slovenian adoption of the draft European Standard prEN 18348 from CEN, prepared by CEN/TC 249 “Plastics”. It specifies criteria and laboratory test methods for distinguishing intrinsically biodegradable plastics from non-biodegradable plastics, mainly for people selecting materials for products that may disperse into the environment. The document focuses on aerobic ultimate biodegradability under controlled laboratory conditions, not on the overall environmental hazard of a product.

What does oSIST prEN 18348:2026 specify?

oSIST prEN 18348:2026 defines a framework for identifying plastic materials that are intrinsically biodegradable. It is intended for use across sectors, especially where products may be released unintentionally or are deliberately dispersed during use.

The document is not tied to one product application. It does not set out a full environmental impact assessment, and it does not determine the rate at which a plastic object will biodegrade in a particular environment.

It is organized into:

• Scope
• Normative references
• Terms and definitions
• Principles
• Requirements
• Test report
• Bibliography

The scope also notes that the methodology is for aerobic conditions typical of most natural habitats. Where permanent anaerobic deposition is expected, other tests and criteria are needed.

What are the key requirements of oSIST prEN 18348:2026?

Sample preparation and reference materials

Clause 5.1 requires both the plastic under test and the reference materials to be tested as powders with the same particle size, with a maximum deviation of 10%. The positive reference is microcrystalline cellulose and the negative reference is polyethylene. In practice, this keeps the comparison fair and makes the result meaningful.

If grinding is needed, cryogenic grinding is required to avoid heat damage. Samples must not be pre-treated by heat, radiation, or natural ageing, so the test reflects the material as supplied.

Test methods and conditions

Clause 5.2 requires testing with one of the listed methods: EN ISO 18830, EN ISO 19679, EN ISO 22404, EN ISO 23977-1, EN ISO 23977-2, or EN ISO 17556. The tests are run under aerobic conditions, typically at 15 °C to 25 °C, and not above 28 °C. For a designer or lab, this means the same material can be checked with approved equivalent respiration-based methods.

Clause 5.2 also allows the constituents of a material to be tested individually. That matters when a formulation contains several organic parts and the biodegradability of each needs to be shown separately.

Test duration and extension

The normal test duration is 24 months. If the sample is still producing CO2 or consuming O2 at the end of that period, the test is extended by 12 months, and then by another 12 months if the same condition continues, up to 48 months.

The extension only applies when the average biodegradation rate is above 1.5% per month over at least 3 consecutive measurement points in the stated late-test windows. In practice, this prevents a slow but still active material from being rejected too early.

Pass criteria for biodegradability

Clause 5.3.1 states that a plastic is biodegradable if it reaches at least 90% mineralisation, either absolute or relative to the reference material, measured by carbon dioxide evolution or oxygen consumption. The test and reference are compared over the same period, usually when both have reached a plateau.

Clause 5.3.5 accepts materials that are readily biodegradable in OECD 301 methods A to F or OECD 310. Clause 5.3.6 accepts chemically unmodified natural-origin materials such as wood, cotton fibre, starch, paper pulp, bagasse and jute without testing.

Constituents, low-level components, and side effects

Clause 5.3.3 requires constituents present between 1% and 15% by total organic carbon (TOC) to be assessed separately. Clause 5.3.4 allows a blend test with at least 15% of the constituent by TOC to confirm biodegradability. Clause 5.3.8 says constituents below 1% by dry mass do not need to prove biodegradability, as long as their total is not above 3% by dry mass.

Clause 5.4 shifts adverse-effect assessment to the final product, taking account of the other components, the expected environment, and the acceptable risk level. For preliminary checks, ISO 5430 and/or ISO 23517 may be used.

Test report

Clause 6 requires the report to identify the material, describe powder preparation and granulometry, state the methods and results, show whether the requirements were met, and include the specific test reports for the methods used. For a buyer or quality team, this is the evidence package to review.

What terms does oSIST prEN 18348:2026 define?

• Intrinsic biodegradability - the potential of a polymer or plastic material to be biodegraded under controlled laboratory conditions.
• Ultimate biodegradation - the breakdown of an organic compound by microorganisms to carbon dioxide, water and biomass in oxygen, or to carbon dioxide, methane and biomass without oxygen.
• Constituent - any pure chemical material or substance that makes up a polymer or plastic material.
• TOC (total organic carbon) - the carbon-content basis used in the document for judging low-level constituents and blend tests.

Who uses oSIST prEN 18348:2026?

This standard is used by designers, material specifiers, test laboratories, quality teams, and buyers who need to distinguish biodegradable plastics from persistent ones. It is especially relevant for products with a high risk of uncontrolled release, including fishing gear, aquaculture and mussel-farming tools, and products such as fireworks.

It supports material selection, laboratory verification, technical claims about biodegradability, and reporting of test results across different industrial sectors.

Which standards are used with oSIST prEN 18348:2026?

• EN ISO 17556 - soil biodegradability by oxygen demand or carbon dioxide evolution.
• EN ISO 18830 - aerobic biodegradation at a seawater/sandy sediment interface by oxygen demand.
• EN ISO 19679 - aerobic biodegradation at a seawater/sediment interface by evolved carbon dioxide.
• EN ISO 22404 - aerobic biodegradation of non-floating materials exposed to marine sediment.
• EN ISO 23977-1 - aerobic biodegradation in seawater by evolved carbon dioxide.
• EN ISO 23977-2 - aerobic biodegradation in seawater by oxygen demand.
• EN ISO 5430 - ecotoxicity testing scheme for soluble decomposition intermediates from biodegradable plastics in the marine environment.
• ISO 23517 - requirements and test methods for soil-biodegradable mulch-film materials, including biodegradation and ecotoxicity.
• ISO 10210 - sample preparation for biodegradation testing, cited for powder preparation.
• OECD 301 / OECD 310 - ready biodegradability tests used as an acceptance route for constituents.

What does the oSIST prEN 18348:2026 document contain?

The document combines a short principles section with detailed requirements for sample preparation, test selection, test duration, pass criteria, constituent handling, and reporting. Figure 1 explains the biodegradation sequence from depolymerization to uptake and respiration.

Clause 5 is the core of the document: it sets the 90% mineralisation criterion, the 24-month test period with possible extensions, and the rules for constituents and reference materials. Clause 6 then defines what the test report must contain so the result can be checked and used in product development or conformity work.

SLOVENSKI STANDARD
01-julij-2026
Polimerni materiali - Lastna biorazgradljivost - Merila in preskusne metode
Plastics - Intrinsic biodegradability - Criteria and test methods
Kunststoffe - Intrinsische biologische Abbaubarkeit - Kriterien und Prüfverfahren
Plastiques - Biodégradabilité intrinsèque - Critères et méthodes d'essai
Ta slovenski standard je istoveten z: prEN 18348
ICS:
83.080.01 Polimerni materiali na Plastics in general
splošno
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

DRAFT
EUROPEAN STANDARD
NORME EUROPÉENNE
EUROPÄISCHE NORM
May 2026
ICS 83.080.01
English Version
Plastics - Intrinsic biodegradability - Criteria and test
methods
Plastiques - Biodégradabilité intrinsèque - Critères et Kunststoffe - Intrinsische biologische Abbaubarkeit -
méthodes d'essai Kriterien und Prüfverfahren
This draft European Standard is submitted to CEN members for enquiry. It has been drawn up by the Technical Committee
CEN/TC 249.
If this draft becomes a European Standard, CEN members are bound to comply with the CEN/CENELEC Internal Regulations
which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

This draft European Standard was established by CEN in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CEN member into its own language and notified to the CEN-CENELEC
Management Centre has the same status as the official versions.

CEN members are the national standards bodies of Austria, Belgium, Bulgaria, Croatia, Cyprus, Czech Republic, Denmark, Estonia,
Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, Netherlands, Norway,
Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland, Türkiye and
United Kingdom.
Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are
aware and to provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without
notice and shall not be referred to as a European Standard.

EUROPEAN COMMITTEE FOR STANDARDIZATION
COMITÉ EUROPÉEN DE NORMALISATION

EUROPÄISCHES KOMITEE FÜR NORMUNG

CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2026 CEN All rights of exploitation in any form and by any means reserved Ref. No. prEN 18348:2026 E
worldwide for CEN national Members.

Contents Page
European foreword . 3
Introduction . 4
1 Scope . 5
2 Normative references . 6
3 Terms and definitions . 7
4 Principles . 7
5 Requirements . 9
5.1 Materials . 9
5.2 Test methods . 9
5.3 Biodegradability criteria. 10
5.4 Negative side effects . 11
6 Test report .11
Bibliography .12

European foreword
This document (prEN 18348:2026) has been prepared by Technical Committee CEN/TC 249 “Plastics”,
the secretariat of which is held by SIS.
This document is currently submitted to the CEN Enquiry.
This document has been prepared under a standardization request addressed to CEN by the European
Commission. The Standing Committee of the EFTA States subsequently approves these requests for its
Member States.
Introduction
Human activities take place within the so-called technosphere, i.e. the system of structures and artefacts
that humans have built over time. With the aim of preserving the natural environment, products are
manufactured, consumed, recycled and disposed of within the technosphere, avoiding as far as possible
their uncontrolled release into the biosphere, understood as the natural environment populated by living
beings. This applies to all products, including biodegradable products, which are also used within the
technosphere and recovered through separate collection and organic recycling in waste treatment
facilities, where they undergo controlled biological processes (such as composting).
Therefore, littering (i.e. the improper disposal of waste in public places or in the natural environment,
resulting in pollution and adverse effects on the environment) is not an action that can be justified or
considered acceptable, as it is never without negative consequences, large or small.
However, there are products that are used in applications that are inherently at risk of uncontrolled
release from the technosphere. For example, tools used in fishing, aquaculture, and mussel farming are
subject to breakage and dispersal because they are immersed in seawater and exposed to the aggressive
action of the sea (storm surges, erosion, etc.). Normally these products are intended to be recovered and
brought ashore for recycling or disposal, but occasionally they break and are dispersed.
Then there are other products that are deliberately released into the biosphere because of the way they
are used. Fireworks, for example, are fired into the air and, when they burst, they break into pieces that
fall to the ground below with little chance of being recovered.
The designer involved in the development of these applications with a high risk of uncontrolled release
is interested in knowing the biodegradability of different materials in order to reduce the ecological risk
of man-made products entering the environment. It is therefore necessary to develop a framework
methodology for the definition of principles, test methods and criteria for the biodegradability of
applications with a risk of dispersion, which can be applied across the sectors concerned without
unnecessary multiplication of approaches.
The methodologies and criteria described in this document may not be appropriate if the release into the
environment occurs in areas where constant anaerobic conditions are expected, such as deep ocean
sediments.
1 Scope
This document defines test methods and criteria for distinguishing intrinsically biodegradable plastic
materials from those that are persistent. Biodegradability is inferred from biodegradation tests
conducted under aerobic conditions, i.e. under the conditions typically found in most natural habitats.
Plastics that undergo ultimate biodegradation under aerobic conditions in a manner similar to natural
polymer materials are defined as biodegradable plastics. This document describes a method for
distinguishing between non-biodegradable plastics, which do not biodegrade even when environmental
conditions are favourable for biodegradation (including aerobic conditions), and biodegradable plastics,
i.e. those that biodegrade upon contact with active microorganisms when environmental conditions are
favourable for biodegradation.
The aim is to demonstrate ultimate aerobic biodegradability of plastic materials, i.e. the intrinsic potential
for conversion to carbon dioxide, water and biomass by aerobic microorganisms in an oxygen-rich
environment, which is representative of most natural environments.
The potential for biodegradation should be verified using alternative tests and criteria, if a deposition in
a permanent anaerobic environment (e.g. deep subsurface environments, wetlands and swamps, anoxic
zones in oceans and lakes) is expected.
NOTE Currently, there are no methodologies or criteria available to verify accumulation due to the lack of
biodegradation of plastics in such anaerobic habitats.
The plastic materials identified as intrinsically biodegradable following this document can be used in the
design of products with a high risk of dispersion whenever the use of biodegradable components is
searched by the designer. Intrinsically non-biodegradable components are not susceptible to
biodegradation and therefore cannot be removed from the environment by the action of micro-
organisms. This factor tends to increase the residence time of products in the environment. In addition,
their eventual degradation, mainly due to abiotic factors, results in persistent fragments (microplastics).
The test scheme described in this document is not specific to any particular application. Rather, it is a
framework methodology that can be used in different industries to identify biodegradable plastics that
can be used to make different types of products and for different applications. For the characterisation
and environmental assessment of products placed on the market containing plastics identified as
biodegradable according to this document, reference is made to the specific product standards, where
available. This document only deals with the definition of intrinsic biodegradability of plastic materials,
without defining the hazard of the products, which requires a specific assessment that is beyond the
scope of this document. The rate of biodegradation of a plastic object as a function of environmental
conditions cannot be determined from this document. Therefore, this document is not sufficient to carry
out an analysis of the ecological risk associated with the dispersal of products, as this requires an
assessment of the intrinsic hazard, of the environmental fate, in addition to the assessment of
biodegradability.
The methodology described in this document does not apply to applications covered by mandatory
regulations.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any amendments) applies.
EN ISO 5430, Plastics — Ecotoxicity testing scheme for soluble decomposition intermediates from
biodegradable plastic materials and products used in the marine environment — Test methods and
requirements
EN ISO 17556, Plastics — Determination of the ultimate aerobic biodegradability of plastic materials in soil
by measuring the oxygen demand in a respirometer or the amount of carbon dioxide evolved
EN ISO 18830, Plastics — Determination of aerobic biodegradation of non-floating plastic materials in a
seawater/sandy sediment interface — Method by measuring the oxygen demand in closed respirometer
EN ISO 19679, Plastics — Determination of aerobic biodegradation of non-floating plastic materials in a
seawater/sediment interface — Method by analysis of evolved carbon dioxide
EN ISO 22404, Plastics — Determination of the aerobic biodegradation of non-floating materials exposed
to marine sediment — Method by analysis of evolved carbon dioxide
ISO 23517, Plastics — Soil biodegradable materials for mulch films for use in agriculture and horticulture
— Requirements and test methods regarding biodegradation, ecotoxicity and control of constituents
EN ISO 23977-1, Plastics — Determination of the aerobic biodegradation of plastic materials exposed to
seawater — Part 1: Method by analysis of evolved carbon dioxide
EN ISO 23977-2, Plastics — Determination of the aerobic biodegradation of plastic materials exposed to
seawater — Part 2: Method by measuring the oxygen demand in closed respirometer
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminology databases for use in standardization at the following addresses:
— ISO Online browsing platform: available at https://www.iso.org/obp/
— IEC Electropedia: available at https://www.electropedia.org/
3.1
intrinsic biodegradability
potential of a polymer or plastic material to be biodegraded established under controlled laboratory
conditions
3.2
ultimate biodegradation
breakdown of an organic chemical compound by microorganisms in the presence of oxygen to carbon
dioxide, water, and mineral salts of any other elements present (mineralization) and new biomass or in
the absence of oxygen to carbon dioxide, methane, mineral salts, and new biomass
3.3
constituent
every pure chemical material or substance of which a polymer or plastic material is composed
4 Principles
Human activities occur within the technosphere, a system of human-made structures and artifacts. To
protect the natural environment (biosphere), products are manufactured, used, recycled, and disposed
of within the technosphere. However, some products, like fishing gear and fireworks, are prone to
uncontrolled release into the biosphere due to their usage conditions. Designers of such products aim to
understand the environmental impact of materials to minimize ecological risks.
As is well known, risk assessment involves knowledge of the hazard and the potential harm caused by
the stressor. The term hazard is used to describe a stre
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