Overview
ISO 10710:2010 - "Water quality - Growth inhibition test with the marine and brackish water macroalga Ceramium tenuicorne" - defines a standardized laboratory method for measuring the inhibition of algal growth caused by substances or mixtures in seawater and brackish water. The test uses the red macroalga Ceramium tenuicorne (selected clones: 7S, 20S, 30S) and is applicable to substances that are easily soluble in water. Tests are typically run for 7 days, with algal length measured to calculate growth rate and derive ECx (effective concentration) values.
Key Topics and Requirements
- Test organism: Ceramium tenuicorne female gametophytes (recommended clones for brackish and marine salinities).
- Salinity range: Applicable for waters with salinities between 4S and 32S; clone selection depends on salinity (brackish vs marine).
- Test principle: Algal tips are incubated in a dilution series of the test sample for 7 days; growth inhibition is determined from reduction in length-based growth rate relative to controls.
- Measured endpoints: Change in algal length (mm), daily growth rate (µ), and calculated ECx values (e.g., EC50).
- Media and nutrients: Use natural or artificial seawater (artificial seawater recipe provided); nutrient stock solutions and media preparation are specified; target pH ~8.0 ± 0.2.
- Controls and validity: Control batches, reference substance tests, and defined validity criteria ensure reproducibility and data quality.
- Test logistics: Guidance on cultivation, apparatus, incubation conditions, measurement procedures, calculations, reporting, and reproducibility.
Applications and Who Uses It
- Environmental and ecotoxicology laboratories conducting standardized growth inhibition tests for marine/benthic risk assessment.
- Regulatory agencies and compliance bodies evaluating wastewater discharges, chemical permits, or environmental impact assessments for coastal and estuarine waters.
- Environmental consultants and monitoring programs assessing pollutant effects on primary producers in marine and brackish ecosystems.
- Researchers comparing toxicity across substances or simulating receiving-water conditions by using natural seawater or artificial seawater media.
Practical uses include toxicity screening of soluble chemicals, effluent toxicity evaluation, comparative ecotoxicity studies, and data generation for ecological risk assessments involving coastal and estuarine habitats.
Related Standards
- ISO 14442 and ISO 5667-16 - referenced for modifications to test poorly soluble materials, sediments, volatile compounds, or metals.
- ISO 8692 and ISO 20079 - related algal test guidance and terminology referenced within the standard.
Keywords: ISO 10710:2010, Ceramium tenuicorne, growth inhibition test, water quality, marine macroalga, ecotoxicity, salinity, artificial seawater, ECx, standard method.