ISO 5667-27-2025 PDF

Full title and description

Water quality — Sampling — Part 27: Guidance on sampling for microplastics in water. This International Standard gives guidance and basic methods for collecting suspended microplastic particles and fibres from a range of water matrices (domestic water, freshwater, seawater, treated and untreated wastewater) to support their subsequent characterization; it addresses grab sampling, cascade filtration and net sampling (e.g., manta, plankton, neuston nets) and clarifies what is excluded (chemical analysis, ecotoxicological methods and sample digestion/pre‑treatment).

Abstract

This document specifies procedures for sampling suspended microplastics in different water environments to obtain representative samples for physical and morphological characterization. It covers approaches for low, medium and high suspended solids (including cascade filtration using successive pore-size filters) and for volumetric/net sampling strategies, and explicitly does not prescribe laboratory chemical or biological analysis or digestion steps.

General information

• Status: Published.
• Publication date: 3 March 2025 (Edition 1, 2025-03).
• Publisher: International Organization for Standardization (ISO).
• ICS / categories: 13.060.45 (Examination of water in general).
• Edition / version: Edition 1 (2025).
• Number of pages: 28 pages (official ISO published PDF).

Scope

ISO 5667-27:2025 provides guidance on sampling methods to collect suspended microplastics (including synthetic and semi-synthetic polymeric materials such as rubber particles) from domestic water, freshwater, seawater and treated/untreated wastewater. It describes representative sampling approaches (grab sampling, cascade filtration across defined pore sizes, and net sampling) appropriate for different suspended-solids loads, but it does not cover analytical chemistry, ecotoxicology, physical characterization techniques in the laboratory, or pre-treatment/digestion methods used for those analyses.

Key topics and requirements

• Definitions and scope of "microplastics" relevant to sampling (particles and fibres, including some semi‑synthetic materials).
• Selection of sampling method by matrix and suspended solids concentration (grab sampling vs cascade filtration vs net sampling).
• Guidance on filtration cascade setups (recommended pore-size ranges and handling to reduce contamination).
• Net sampling recommendations (manta, plankton, neuston nets) including tow procedures and volume estimation.
• Sample handling, transport and prevention of contamination in the field (procedural controls to minimise airborne and cross-contamination during collection).
• Notes on representativeness, reporting of sampling conditions and metadata required for interpretation of results.
• Explicit exclusions: no prescriptions for laboratory chemical analyses, digestion methods or ecotoxicological testing.

Typical use and users

Practitioners in environmental monitoring, laboratory managers, water utilities, consultants, regulators, researchers studying microplastic occurrence and fate, and organizations designing monitoring programmes will use this guidance to plan and document microplastic sampling campaigns that produce reproducible, interpretable samples for downstream analysis.

Related standards

ISO 5667-27:2025 is part of the ISO 5667 series (Water quality — Sampling) and is intended to be used alongside general sampling and sample‑handling parts of the series (for example ISO 5667-1 and ISO 5667-3 for sampling principles and preservation/handling). The standard was developed under ISO/TC 147 (Water quality) subcommittee SC 6 and working group(s) addressing microplastic sampling.

Keywords

microplastics, sampling, water quality, cascade filtration, manta net, plankton net, neuston net, grab sampling, suspended solids, ISO 5667.

FAQ

Q: What is this standard?

A: ISO 5667-27:2025 is an International Standard that provides guidance on methods to sample suspended microplastics (particles and fibres) in various water matrices to obtain representative samples for subsequent characterization.

Q: What does it cover?

A: It covers field sampling methods (grab sampling, cascade filtration using a series of filters, and net sampling such as manta/plankton/neuston nets), sample‑handling precautions to reduce contamination, and metadata/reporting recommendations. It does not cover laboratory chemical analyses, digestion/pre‑treatment protocols or ecotoxicological testing.

Q: Who typically uses it?

A: Environmental monitoring teams, water utilities, research laboratories, consultants, regulatory agencies and programme designers use the standard to ensure that samples for microplastic analysis are collected and documented in a consistent, reproducible way.

Q: Is it current or superseded?

A: Current — ISO 5667-27 was published as Edition 1 on 3 March 2025 and is an active International Standard. Users should check for future amendments or revisions through national bodies or ISO for the latest status.

Q: Is it part of a series?

A: Yes — it is part of the ISO 5667 series on water quality sampling and was developed under ISO/TC 147/SC 6 (Sampling). It is intended to be used together with other relevant parts of ISO 5667 (for example parts covering general sampling principles and sample preservation/handling).

Q: What are the key keywords?

A: microplastics; sampling; water quality; cascade filtration; manta net; grab sampling; suspended microplastics; ISO 5667.