ISO 14507:2003

Overview

ISO 14507:2003 - Soil quality - Pretreatment of samples for determination of organic contaminants - specifies laboratory pretreatment methods to prepare soil test samples for analysis of organic contaminants. The standard defines three routes depending on compound volatility and sample properties: (1) volatile organic compounds, (2) moderately volatile to non‑volatile compounds where accurate, reproducible results are required (including cryogenic grinding), and (3) non‑volatile compounds or field‑moist requirements where reduced accuracy is acceptable or particles are already < 2 mm. The goal is to produce a test portion whose contaminant concentration reflects the original soil without altering the chemical species.

Key topics and requirements

• Three pretreatment paths:
  • Volatile organics (boiling point < 300 °C): obtain core subsamples and extract promptly; composite samples risk severe losses of volatiles.
  • Moderately volatile/non‑volatile (boiling point > 300 °C) requiring high accuracy: chemical drying with liquid nitrogen (−196 °C) and cryogenic crushing in a cross‑beater mill with a 1 mm sieve to improve homogeneity and extraction yield.
  • Non‑volatile or field‑moist samples: do not dry or grind if extraction requires field‑moist material or if particles are already