Overview
ISO 19827:2016 - "Water quality - Determination of the acute toxicity to the freshwater rotifer Brachionus calyciflorus" - specifies a standardized 24-hour bioassay to determine lethal effects (24 h LC50) of toxicants on the freshwater rotifer Brachionus calyciflorus. The method covers soluble chemicals, stable suspensions, industrial or sewage effluents (after appropriate treatment), freshwaters and aqueous extracts. Tests are performed under controlled laboratory conditions and are intended for reliable aquatic toxicity data for water quality assessment and ecotoxicology.
Key Topics and Technical Requirements
- Test organism: Female Brachionus calyciflorus from lab cultures or hatched from cysts (hatching procedure in Annex A).
- Exposure: 24-hour acute exposure with mortality assessment and calculation of 24 h LC50.
- Test design:
- Minimum five concentrations plus control; geometric dilution series.
- Range-finding: typical separation factor 10 for chemicals; effluents commonly use 1:1 dilutions.
- Definitive test: dilution factor not exceeding 3.2 for chemicals; effluents/waters typically 1:1.
- Replication: six replicates per concentration and control (microplate 48-well format recommended).
- Environment & apparatus:
- Incubation in the dark at 25 ± 1 °C.
- Use of disposable 48-well microplates, stereomicroscope, pipettes and temperature-controlled chamber.
- Samples & preparation:
- Sampling and handling guidance (ISO 5667-16 referenced): test ideally within 12 hours; cooling/freezing protocols given if delays occur.
- Decantation, filtration or centrifugation where necessary to remove interfering particulates.
- Controls & references:
- Reference substances: potassium dichromate (K2Cr2O7) or copper sulfate (CuSO4·5H2O). Note safety caution for K2Cr2O7.
- Measurements & reporting:
- Dissolved oxygen must be measured (ISO 5814 referenced); data analysis guidance (ISO/TS 20281 referenced).
- Annexes include artificial water recipe (Annex B) and performance data (Annex C).
Applications
- Regulatory compliance testing for effluents and surface waters.
- Ecotoxicological evaluation of chemicals, formulations and wastewater discharges.
- Environmental monitoring, risk assessment and product safety screening using a sensitive zooplankton bioassay.
- Comparative toxicity screening in laboratory and contract testing environments.
Who uses this standard
- Environmental testing laboratories and contract bioassay facilities
- Regulatory agencies and water quality assessors
- Chemical manufacturers, formulators and wastewater treatment operators
- Ecotoxicologists and research institutions
Related Standards
ISO 19827 provides a reproducible, recognized rotifer acute toxicity test (24 h LC50) for water quality and ecotoxicology applications, helping stakeholders generate comparable, regulatory-grade aquatic toxicity data.