To effectively reduce the accumulation of plastic waste, biodegradable and compostable materials must decompose under the intended disposal conditions, within a reasonable timeframe, and without releasing toxic substances.
International standards provide an objective and reliable way to verify that these criteria are met. Testing can be conducted in accordance with various EN, ISO, OECD, ASTM, and national standards, depending on the conditions under which the material should decompose and the intended goal of the testing project. For R&D purposes, a relatively simple biodegradability screening is typically sufficient, whereas a full compostability assessment is required to demonstrate that a material can be efficiently processed through the biowaste collection stream.
The regulatory context should also be considered. In the EU, the new Packaging and Packaging Waste Regulation (PPWR) will require certain compostable packaging to comply with harmonized standards by 12 February 2028. Compostability testing for PPWR compliance should therefore be performed in accordance with the updated industrial compostability standard or the new home compostability standard once these become available.1
Table 1: Overview of selected biodegradation, ecotoxicity, and compostability testing standards
Standard | Analyzed parameter(s)* | Typical applications |
Water solubility/extraction behavior of polymers | REACH microplastics restriction compliance; polymer solubility exemption documentation | |
Growth inhibition of freshwater microalgae and cyanobacteria; ErC50, NOEC | Aquatic hazard characterization under REACH; TSCA new chemical assessments | |
Acute immobilization of Daphnia magna; EC50 | Aquatic hazard characterization under REACH; TSCA new chemical assessments | |
Acute toxicity to earthworms (Eisenia foetida ); LC50 | Terrestrial hazard characterization under REACH; crop protection product assessments | |
Seedling emergence and early growth inhibition in higher plants; ECx/ERx, NOEC | Non-target plant risk assessment under REACH and Regulation (EC) No. 1107/2009 | |
Respiration inhibition of activated sludge microorganisms; EC50, NOEC | Toxicity to microorganisms under REACH; wastewater treatment compatibility screening | |
Ready biodegradability in freshwater (multiple sub-methods: A–F); % mineralization | REACH environmental fate requirements; surfactant biodegradability under Regulation (EC) No. 648/2004 | |
Aerobic biodegradability in seawater; % DOC removal or O2 consumption | REACH ready biodegradability; REACH microplastics restriction; EU Ecolabel for lubricants | |
Ready biodegradability by CO2 evolution in sealed vessels (headspace test); % ThIC | REACH ready biodegradability; surfactant compliance under Regulation (EC) No. 648/2004; REACH microplastics restriction | |
EN 13432 | Biodegradability, disintegration, ecotoxicity, and heavy metal content | Industrial compostability certification for packaging; EU Packaging and Packaging Waste Regulation (PPWR) compliance** |
EN 14995 | Biodegradability, disintegration, ecotoxicity, and heavy metal content | Industrial compostability certification for plastic materials other than packaging |
ISO 14855 | Aerobic biodegradability under controlled composting conditions; % CO2 evolution | R&D biodegradability screening before full compostability assessment |
ISO 17088 | Biodegradability, disintegration, ecotoxicity, and heavy metal content | Industrial compostability certification; equivalent to EN 13432 for international markets |
ISO 17556 | Aerobic biodegradability in soil; % CO2 evolution or O2 consumption | Soil biodegradation assessment for plastics, packaging, and agricultural materials |
ISO 23977 | Aerobic biodegradability of plastics in seawater by CO2 evolution or O2 consumption | Marine biodegradability assessment; certification for marine-exposed plastic materials |
ASTM D6400 | Biodegradability, disintegration, ecotoxicity, and heavy metal content | Industrial compostability labeling in the United States; functionally comparable to EN 13432 |
ASTM D6691 | Aerobic biodegradability in seawater by CO2 evolution; % carbon conversion | Marine biodegradability claims for plastics; marine environment product assessments |
AS 5810 | Biodegradability, disintegration, ecotoxicity, and heavy metal content at ambient temperature | Home compostability certification (Australia); used internationally pending new EN standard |
NF T51-800 | Biodegradability, disintegration, ecotoxicity, and heavy metal content at ambient temperature | Home compostability certification (France); used internationally pending new EN standard |
* Parameter glossary:
EC50 — Concentration causing 50% reduction in the measured endpoint relative to controls.
ErC50 — EC50 based on growth rate; used specifically in algal toxicity tests.
LC50 — Concentration causing 50% mortality within the defined exposure period.
NOEC — Highest tested concentration at which no statistically significant effect is observed.
LOEC — Lowest tested concentration at which a statistically significant effect is observed. The concentration step immediately above the NOEC.
ECx / ERx — Concentration (ECx) or application rate (ERx) causing x% change in the measured endpoint; common values are EC25 and EC50.
ThIC — Theoretical inorganic carbon: the maximum CO2 that would be produced by complete mineralization of the test substance. Used to calculate % biodegradation in headspace tests.
% mineralization — Percentage of the test substance's carbon converted to CO2 during the test.
% DOC removal — Reduction in dissolved organic carbon concentration over the course of the test.
* The current EN 13432 standard is due to be updated and can be used as guidance until the new version is adopted.
Industrial compostability testing
The purpose of industrial compostability testing is to ensure that biodegradable materials can be safely and effectively disposed of through the organic waste stream. In Europe, EN 13432 is the harmonized standard for determining whether packaging materials can be classified as industrially compostable. However, the current edition from the year 2000 is due to be updated in the near future to ensure that composting times and acceptable contamination levels better reflect the actual conditions in biowaste treatment facilities.2
To comply with EN 13432:2000, packaging must meet the minimum requirements for the following four characteristics:
Characterization of constituents: The material must contain at least 50% volatile solids and must not contain heavy metals or other toxic chemicals in concentrations that may harm the environment.
Biodegradation: At least 90% of the material must biodegrade within 6 months in aerobic conditions. The temperature is generally set at 58 ± 2 °C, as specified in the ISO 14855 standard.
Disintegration: After 12 weeks of aerobic composting, at least 90% of the test material (by dry weight) must pass through a 2 mm sieve.
Ecotoxicity/compost quality: The resulting post-disintegration compost must not have a detrimental effect on plant growth.
The end user must recognize the packaging as compostable to ensure it is disposed of correctly. It should also be clearly stated whether the “compostable ” label refers to the product inside the packaging or the packaging itself.
Other commonly applied industrial compostability standards that follow a similar testing procedure include EN 14995, ISO 17088, and ASTM D6400, which were all designed for compostable plastics. In addition, ISO 14855 on ultimate aerobic biodegradability can be used to compare alternative material formulations during product development, before confirming compostability using a more comprehensive standard.
Home compostability testing
The conditions of a home compost differ considerably from one location to another, making it difficult to define typical temperature or humidity parameters. This is why there is currently no European or international reference standard for home compostability. A European harmonized standard will be developed soon, however, prompted by the PPWR.3
Until the new European standard is published, Australian standard AS 5810 and French standard NF T51-800 are most typically used to evaluate compostability in home composts.
The parameters covered by AS 5810 are largely the same as those given in EN 13432, with the most significant differences being the conditions under which biodegradation should occur and the times allowed for decomposition. The acceptance criteria for home compostable packaging are the following:
Characterization: The material contains at least 50% of volatile solids, and heavy metal content does not exceed the specified levels, which are the same as in EN 13432.
Biodegradability: At least 90% w/w of the material degrades in aerobic conditions within 12 months at 25 ± 5°C. Testing is performed in accordance with EN 14855.
Disintegration: After 180 days in a controlled composting environment, at least 90% w/w of the material passes through a 2 mm sieve. Any remaining material must not be distinguishable from the compost material with the naked eye at a distance of 500 mm.
Compost quality: The resulting compost must not negatively impact plant growth or worm survival.
Similarly to industrial compostability tests, all individual components must meet these requirements for the whole material to be labeled home compostable.
Biodegradation in soil and marine environments
Due to the highly controlled conditions, passing the criteria for compostability does not prove that a material biodegrades in the natural environment. This is why separate biodegradation tests are needed to assess degradation in soil or water, where the material may end up accidentally or as a result of use in agriculture, horticulture, forestry, or fishing.
ISO 23517 is the most commonly used standard for assessing biodegradability in soil. The parameters it covers include characterization of constituents, biodegradation, and ecotoxicity. Although the standard is primarily aimed at agricultural and horticultural mulch films, it may also be used to evaluate other plastic materials.
Biodegradation in marine environments is usually assessed using a combination of standards that cover aerobic biodegradation (ISO 19679, ASTM D6691) and disintegration (ISO 23832) in simulated marine conditions. Testing can also be performed in real marine conditions using an in-house method.
Our biodegradability testing solutions
Measurlabs offers biodegradability and compostability testing in accordance with the standards described above. If the goal is to compare several materials during the R&D phase, we recommend biodegradability screening based on the ISO 14855 standard. This is currently our most popular service, for which we can offer a competitive price if at least four different materials are tested at once.
We also provide full compostability assessments in both industrial and home composting conditions. However, for this purpose, it may make sense to wait until the new harmonized standards are published, as PPWR compliance testing will need to be conducted in accordance with them. We will follow the standardization process closely and update our service offering accordingly.
Do not hesitate to contact our experts using the form below to discuss the most suitable testing solutions for your material.
References:
1 Article 9(1) of Regulation (EU) 2025/40 on packaging and packaging waste. This deadline may be pushed forward if the harmonized standards are not developed on schedule, to give companies sufficient time to comply.
2 See European harmonized standards on packaging and packaging waste for recognition of EN 13432 under the previous packaging and packaging waste Directive 94/62/EC. The need to update the standard is stated in Recital (58) of Regulation (EU) 2025/40.
3 Article 9(6) of Regulation (EU) 2025/40 on packaging and packaging waste states that the Commission will request European standardization organizations by 12 February 2026 to create harmonized home compostability standards.