Overview
EN ISO 17402:2011 (ISO 17402:2008) - "Soil quality - Requirements and guidance for the selection and application of methods for the assessment of bioavailability of contaminants in soil and soil materials" - gives guidance for selecting and applying methods to assess the bioavailability of contaminants in soils and sediments. Endorsed by CEN in 2011, it covers metals (including metalloids), organic contaminants (including organometal compounds) and naturally occurring pedo‑geochemical metal sources. The standard does not prescribe a single “best” method; instead it defines boundary conditions, underlying principles and the minimal requirements for development and application of methods whose results can be used in risk‑assessment approaches.
Key Topics
- Scope and applicability: soil, soil materials and sediments; metals, metalloids, organic contaminants and natural geogenic metal sources.
- Concepts of bioavailability: definitions and links between bioavailability, biological effects and bioaccumulation.
- Method types:
- Chemical methods (e.g., extraction and leaching tests) to estimate environmental availability and mobility.
- Ecotoxicological tests (biological assays) that measure accumulation or effects on representative organisms.
- Exposure pathways: human (ingestion, dermal contact, inhalation, groundwater), higher animals, soil organisms and plants.
- Method selection and application: requirements and decision criteria for choosing appropriate methods given protection goals and soil functions.
- Requirements for method development: minimal quality criteria, boundary conditions and validation considerations.
- Use in risk assessment: how bioavailability estimates can refine exposure assessment compared to conservative total‑concentration approaches.
Applications
Who uses EN ISO 17402:2011 and why:
- Environmental consultants and remediation specialists - refine contaminated site characterisation and select appropriate bioavailability tests to inform remediation decisions.
- Risk assessors and regulators - apply standardized guidance to support exposure assessments and site-specific risk evaluation.
- Laboratories and method developers - design, validate and report chemical or ecotoxicological methods that meet minimal requirements.
- Soil scientists and ecotoxicologists - interpret bioavailability in relation to soil functions, organisms and long‑term sequestration processes.
Practical uses include contaminated land assessment, remediation planning, monitoring, and deciding whether total concentration or bioavailable fraction should drive risk management.
Related Standards
- EN ISO 17402:2011 is part of the ISO/TC 190 “Soil quality” family.
- Annexes reference international standards for toxicity testing of sediment organisms and additional soil‑quality test standards.
For site assessments, combine EN ISO 17402 guidance with jurisdictional regulatory standards and validated laboratory methods to ensure defensible, site‑specific conclusions about contaminant bioavailability.
