ISO 16636:2025

Overview

ISO 16636:2025 - Plastics - Disintegration field test of plastics under water environmental conditions specifies a standardized field method to determine the degree of disintegration of plastic materials floating in water. The test is performed under natural environmental conditions (sublittoral zones, shores of lakes or rivers) with samples immersed at depths between 1.5 m and 3 m. This is a field disintegration test (physical breakdown into fragments), not a biodegradation test, and cannot be used alone to claim “biodegradable in marine environment” or similar unqualified biodegradability claims.

Key technical topics and requirements

• Test principle: Short-term immersion of representative samples (preferably films, fibres, nonwovens or similar) in perforated containers that allow free sample movement; disintegration quantified by weight loss or film thickness reduction (µm).
• Sample preparation & thickness: Film thickness must be measured by ISO 4591 or ISO 4593 methods; use identical form and thickness as the intended final use.
• Reference (positive control) materials: Examples include PHBH film, PCL film (50–500 µm) and/or ashless cellulose filters as positive controls.
• Immersion depth & location: Field immersion in sublittoral or freshwater shore zones, 1.5–3 m from the water surface.
• Sampling strategy: Maintain weight retention ≥50% where possible to reduce fragment loss during recovery; take multiple sampling intervals and thicknesses to derive reliable disintegration rates. Preferred immersion period is within three months, extendable for slow-disintegrating materials.
• Monitoring & analysis: Photographic documentation, weight/thickness calculations, optional microbial counts and community analysis, and recommended monitoring of environmental parameters (temperature, DOC, etc.).
• Limitations: Not suitable for assessing degradation caused by heat or light exposure; not a substitute for laboratory biodegradation tests.

Practical applications and users

Who uses ISO 16636:2025:

• Manufacturers and developers of compostable/biodegradable plastics seeking field-relevant disintegration data.
• Independent testing laboratories and accredited facilities following ISO/IEC 17025 practices.
• Environmental scientists and research institutions studying plastic fragmentation in aquatic environments.
• Regulators, product stewards, and purchasers requiring standardized disintegration evidence for environmental risk assessments or product specifications.

Practical value:

• Produces field-based, comparable data on physical disintegration behavior of floating plastics.
• Helps evaluate product end‑of‑life behavior in real aquatic conditions and supports R&D and environmental performance claims when combined with appropriate biodegradation tests.

Related standards

• ISO 4591, ISO 4593 (film thickness measurement)
• ISO/IEC 17025 (laboratory competence)
• Laboratory biodegradation and degradation standards referenced in the ISO text: ISO 18830, ISO 19679, ISO 22404, ISO 23977‑1, ISO 23977‑2, ISO 23832 and ISO 22766.

Keywords: ISO 16636:2025, disintegration field test, plastics disintegration test, marine disintegration, sublittoral, film thickness, weight loss, biodegradable plastics.