ISO 5667-16:2017

Overview

ISO 5667-16:2017 - Water quality - Sampling - Part 16: Guidance on biotesting of samples provides practical guidance for sampling, pre-treatment, handling, performance and evaluation of environmental samples used in biological (ecotoxicological) tests. The document focuses on solving experimental problems that arise when biotesting complex matrices such as treated municipal and industrial wastewater, groundwater, fresh water, leachates/eluates, pore water and sediments. It covers organism-based biotests (single-species in vivo and in vitro), and aspects applicable to single-cell bioassays and biodegradation studies. This standard does not cover bacteriological water examination (see ISO 19458).

Key topics and technical requirements

• Test design and evaluation
  • Guidance on replicates, lowest ineffective dilution (LID), hypothesis testing and concentration–response relationships.
  • Statistical analysis recommendations consistent with current state of the art.
• Sampling and transportation
  • Advice on sampling equipment, sample containers, filling status, identification, sub-sampling and transport to minimize changes in sample integrity.
  • Measures to prevent contamination during sampling and recommended sampling quality-control techniques.
• Pre-treatment and storage
  • Preservation, storage, thawing and homogenization procedures.
  • Separation of soluble and particulate fractions, preconcentration and extraction methods for poorly soluble substances.
  • pH adjustment and preparation of stock solutions/test batches, including approaches for water‑soluble and poorly soluble substances.
• Impairment control
  • Identification and mitigation of sample-related issues: volatilization, foaming, adsorption, precipitation/flocculation, degradation, turbidity and colour interference.
• Apparatus, cleaning and QA
  • Selection and cleaning of equipment, quality assurance for biotesting, and reporting requirements to ensure reliable, reproducible results.

Practical applications and users

ISO 5667-16:2017 is intended for:

• Environmental and analytical laboratories performing ecotoxicological testing, bioassays and biodegradation studies.
• Water quality managers assessing the biological effects of effluents, leachates and sediment pore waters.
• Consultants, researchers and regulatory bodies engaged in environmental monitoring, compliance testing and impact assessment. Practical use cases include preparing representative samples for toxicity tests, troubleshooting assay interference from complex matrices, and ensuring defensible data through proper sampling and pre-treatment.

Related standards

• ISO 5667 series (other parts addressing sampling methods for waters and sediments)
• ISO 19458 (bacteriological examination of water) - referenced for microbiological methods

Keywords: ISO 5667-16:2017, water quality, biotesting, sampling guidance, environmental samples, ecotoxicological testing, wastewater, sample pre-treatment, bioassays.