ISO 10253:2024

Overview

ISO 10253:2024 specifies a laboratory method to assess the inhibition of growth of marine algae-specifically, Skeletonema sp. and Phaeodactylum tricornutum-caused by substances or mixtures in seawater or environmental water samples, such as effluents and elutriates. This standard is fundamental in evaluating the ecotoxicological impact of chemicals and wastewater discharges on marine ecosystems, helping ensure water quality and environmental compliance.

The method is designed for water-soluble substances that remain stable in testing conditions. With additional modifications as referenced in ISO 14442 and ISO 5667-16, it can also be applied to poorly soluble or volatile substances and complex materials such as sediments and their elutriates.

Key Topics

• Marine Algal Growth Inhibition: The core of ISO 10253:2024 is to measure the effect of test substances on the growth rate of two algae species that are common and ecologically significant in coastal waters.
• Test Procedure: The protocol involves culturing algae in controlled conditions with various concentrations of test substances. Growth is monitored over 72 hours by measuring cell density.
• Preparation and Maintenance of Cultures: Detailed guidelines are provided on maintaining algal cultures, ensuring their health and purity for reliable results.
• Growth Medium and Apparatus: Specifications for synthetic and natural seawater, nutrient solutions, and required laboratory equipment to avoid contamination and ensure accuracy.
• Validity and Quality Criteria: The method specifies required increases in algal density and limits on pH shifts to ensure valid, reproducible results.
• Data Analysis: Calculation of EC10 and EC50 (Effective Concentration to inhibit growth by 10% and 50%, respectively) and plotting concentration-response curves for robust interpretation.

Applications

ISO 10253:2024 is widely used by environmental laboratories, regulatory authorities, and research organizations to:

• Assess Ecotoxicity of Chemicals: Used in regulatory submissions for new substances, the standard helps determine the potential impact of chemicals used in industries such as oil and gas, shipping, and manufacturing when released into marine environments.
• Monitor Effluent Quality: Essential for wastewater treatment plants and industrial facilities to evaluate and manage the potential environmental impact of effluents.
• Research and Risk Assessment: Supports scientific studies aiming to understand the effects of pollution on primary producers in marine ecosystems, providing data critical for marine risk assessments.
• Compliance and Reporting: Frequently referenced in national and international regulations for marine environmental protection. Fulfilling ISO 10253:2024 demonstrates adherence to best practices in water quality monitoring.

Related Standards

For broader and more specific ecotoxicological assessments, the following ISO standards are closely related:

• ISO 5667-16: Water quality-Sampling-Part 16: Guidance on biotesting of samples. Provides practical direction for sampling and preparation for biological tests.
• ISO 14442: Water quality-Guidelines for algal growth inhibition tests with poorly soluble materials, volatile compounds, metals and waste water.
• ISO 8692: Water quality-Fresh water algal growth inhibition test with unicellular green algae (for freshwater environments).

By integrating ISO 10253:2024 into environmental monitoring and compliance strategies, organizations can ensure reliable, internationally recognized assessments of marine water quality and the ecological impact of waterborne substances. This standard plays a critical role in safeguarding aquatic environments and supporting sustainable management of marine resources.