Overview
ISO 15587-1:2002 is an internationally recognized standard developed by ISO for the analysis of water quality. Specifically, it outlines an empirical method for extracting trace elements from water samples using aqua regia digestion. This method applies to all types of water containing less than 20 g/L of suspended solids and less than 5 g/L of total organic carbon (TOC). The aqua regia digestion process, while not guaranteeing complete release of all elements, is widely considered suitable for most environmental applications in water quality assessment.
Key Topics
- Aqua Regia Digestion: The standard describes a procedure in which water samples are treated with aqua regia-a solution of nitric acid and hydrochloric acid mixed in a 1:3 volume ratio-to extract trace elements.
- Scope of Applicability: Suitable for various types of water including drinking water, surface water, and wastewater, provided suspended solids and TOC concentrations are within specified limits.
- Element Coverage: The technique is applicable for the determination of a wide array of metals and elements such as Ag, Al, As, B, Ba, Be, Ca, Cd, Co, Cr, Cu, Fe, Hg, K, Mg, Mn, Mo, Na, Ni, P, Pb, Sb, Se, Sn, Sr, Tl, V, and Zn.
- Limitations: Not suitable for digesting highly refractory compounds like SiO₂, TiO₂, and Al₂O₃. Additionally, the presence of chloride in the digestion solution may interfere with some analytical methods.
- Flexibility in Equipment: While specifying the digestion composition, temperature, and duration, the standard allows the use of various compliant laboratory apparatus.
- Sample Handling and Reporting: Stresses adherence to proper sample preservation, handling, and detailed reporting in alignment with ISO standards.
Applications
ISO 15587-1:2002 is primarily used by laboratories, regulatory agencies, and industries involved in environmental monitoring, water treatment, and quality control. Key practical applications include:
- Environmental Monitoring: Assessing trace metal pollution in surface waters, groundwater, and effluents to comply with environmental protection regulations.
- Drinking Water Testing: Ensuring the water supply is free from harmful concentrations of heavy metals and trace elements.
- Industrial Water Analysis: Monitoring process water in manufacturing, mining, or chemical industries to manage waste streams and maintain compliance.
- Research and Development: Supporting scientific studies on trace elements in various water matrices.
The digestion method established by this standard is suitable for both routine analysis and specialized investigations, offering reliable preparation of samples for subsequent analytical techniques like atomic absorption spectroscopy (AAS) and inductively coupled plasma (ICP) spectrometry.
Related Standards
For a robust water analysis regime and to meet best practice in water quality assessment, consider these related ISO standards:
- ISO 3696:1987: Water for analytical laboratory use-Specification and test methods
- ISO 5667-3:1994: Water quality-Sampling-Guidance on the preservation and handling of samples
- ISO 15587-2: Water quality-Digestion for the determination of selected elements in water-Part 2: Nitric acid digestion
By implementing ISO 15587-1:2002, laboratories and organizations can ensure consistent, internationally recognized procedures for the extraction and determination of trace elements in water, thereby supporting environmental safety, regulatory compliance, and high analytical quality.
Open preview (PDF)Water quality — Digestion for the determination of selected elements in water — Part 1: Aqua regia digestion