ISO 11268-2:2023

Overview

ISO 11268-2:2023 - Soil quality - Effects of pollutants on earthworms - Part 2 specifies a standardized chronic ecotoxicity test to determine effects of soil contaminants and chemicals on the reproduction of earthworms, primarily Eisenia fetida and Eisenia andrei. The method evaluates habitat function of soils by measuring reproductive output (mean offspring per container after eight weeks’ incubation) following dermal and alimentary uptake. The 2023 third edition updates reference substance criteria and adds guidance for alternative species and tropical testing.

Key technical topics and requirements

• Scope and limits
  • Applicable to contaminated soils, amended soils, post‑remediation soils, agricultural sites, and waste materials.
  • Not suitable for substances with air/soil partition coefficient > 1 or vapour pressure > 300 Pa at 25 °C.
  • Persistence of a substance during the test is not accounted for.
• Test design
  • Preliminary (screening) and definitive multi‑concentration or limit tests with defined replicates.
  • Preparation of test mixtures: contaminated soil testing or spiking of control/standard soils.
  • Addition and handling of test organisms and controlled incubation.
• Measurements and endpoints
  • Primary endpoint: reproduction (offspring count at 8 weeks). Secondary: adult survival and growth.
  • Reference substance use (boric acid concentration revised in this edition).
• Procedure support
  • Detailed procedures for culturing (E. fetida/E. andrei) and alternative species in informative annexes.
  • Annexes cover tropical conditions (A), alternative species protocols (B, C), culturing (D), water‑holding capacity (E), counting juveniles (F), and performance criteria (G).
• Data analysis and reporting
  • Calculation of NOEC/LOEC/ERx/ECx, statistical analysis requirements, validity criteria and mandatory test report elements.

Practical applications and users

• Environmental laboratories conducting soil ecotoxicology bioassays.
• Environmental consultants and remediation practitioners assessing contaminated sites.
• Regulatory agencies evaluating chemical or waste impacts on soil fauna.
• Research groups studying soil health, bioavailability, and sublethal effects.
• Chemical and waste producers performing hazard assessment for terrestrial exposure.

Related standards and references

ISO 11268-2 integrates with other ISO soil quality methods such as:

• ISO 10390 (pH), ISO 10694 (organic/total carbon), ISO 11260 (cation exchange), ISO 11277 (particle size), ISO 11465 (water content), and ISO 18400-206 (soil sampling for biological assessment).

Keywords: ISO 11268-2, soil quality, earthworm reproduction test, Eisenia fetida, Eisenia andrei, soil ecotoxicology, contaminated sites, chronic toxicity test, dermal and alimentary uptake.