🔬 Metals in water — ICP-OES
In short
Determination of 35 elements in water by inductively coupled plasma optical emission spectrometry (ICP-OES) — dissolved elements, elements bound to particles and total content, in ground, surface, raw and drinking water and in waste water. The test is performed according to PN-EN ISO 11885:2009; Elements determined: 35 (Al, Sb, As, Ba, Be, Bi, B, Cd, Ca, Cr, Co, Cu, Ga, In, Fe, Pb, Li, Mg, Mn, Mo, Ni, P, K, Se, Si, Ag, Na, Sr, S, Sn, Ti, W, V, Zn, Zr). The procedure comprises 7 steps; it is used for: Waste water — one of the reference methods for many metals (Journal of Laws 2019, item 1311, Annex 12), Monitoring of surface and ground waters — e.g. arsenic, zinc, copper (Journal of Laws 2021, item 1576, Annex 8), Drinking, raw, ground and surface water — dissolved elements, elements bound to particles and total content (clause 1).
At a glance
- Standard: PN-EN ISO 11885:2009
- Category: Physicochemistry
- Procedure steps: 7
- Elements determined: 35 (Al, Sb, As, Ba, Be, Bi, B, Cd, Ca, Cr, Co, Cu, Ga, In, Fe, Pb, Li, Mg, Mn, Mo, Ni, P, K, Se, Si, Ag, Na, Sr, S, Sn, Ti, W, V, Zn, Zr)
- Forms: dissolved, bound to particles, total (after digestion or as the sum of the two fractions)
- Suspended solids in waste water: below 2 g/l (clause 1)
Overview
STATUS (as of 29.10.2026). PN-EN ISO 11885:2009 — English version (with a Polish title in the PKN catalogue), published 23.07.2009, implements EN ISO 11885:2009 and ISO 11885:2007 [IDT]; it replaced PN-EN ISO 11885:2001 (the Polish version). The standard is current — no withdrawal note. ISO 11885:2007 (second edition, replacing the first edition of 1996) is published in the ISO catalogue, with no newer edition.
SCOPE (clause 1). A method for determining dissolved elements, elements bound to particles and their total content in different types of water (e.g. ground, surface, raw and drinking water and waste water) for 35 elements: aluminium, antimony, arsenic, barium, beryllium, bismuth, boron, cadmium, calcium, chromium, cobalt, copper, gallium, indium, iron, lead, lithium, magnesium, manganese, molybdenum, nickel, phosphorus, potassium, selenium, silicon, silver, sodium, strontium, sulfur, tin, titanium, tungsten, vanadium, zinc and zirconium. Taking interferences into account, the same elements can be determined in digests of water, sludges and sediments (e.g. according to ISO 15587-1 or ISO 15587-2). The method is suitable for waste water with suspended solids below 2 g/l; extension to other matrices requires the user to demonstrate that the additional interferences have been considered and corrected.
WAVELENGTHS AND LIMITS OF QUANTIFICATION (clause 5, Table 1). The standard gives recommended wavelengths, achievable limits of quantification for radial and axial viewing of the plasma and the most important spectral interferences — e.g. cadmium 214.441 nm: about 1 µg/l (radial) and 0.9 µg/l (axial), interfered by As, Cr, Fe, Sc, Sb; arsenic 193.696 nm: about 5 µg/l and 14 µg/l, interfered by Al, Co, Fe, W, V. The values come from an interlaboratory trial (Annex B); actual limits depend on the instrument, detector, sample introduction system and matrix. The limit of detection is 3 s₀ and the limit of quantification is 3 limits of detection (9 s₀), where s₀ is the standard deviation of the results of at least 3 measurements of the reagent blank solution (3.10–3.11).
LEGAL REQUIREMENTS. Waste water: PN-EN ISO 11885 is one of the reference methods for, among others, antimony, arsenic, boron, total chromium, zinc, cadmium, cobalt, copper, molybdenum, nickel, lead and selenium (Journal of Laws 2019, item 1311, Annex 12), with a note that the method is particularly recommended when several elements are determined in one sample. Monitoring of surface and ground waters: the standard transposing ISO 11885 is a method for, among others, arsenic, zinc and copper (Journal of Laws 2021, item 1576, Annex 8).
WHAT WE DO NOT GIVE HERE. The publicly available text of the standard covers clauses 1–5 (up to the beginning of Table 1). Interferences (clause 6), reagents (clause 7), apparatus (clause 8), sampling and preservation (clause 9), procedure (clause 10), expression of results (clause 11), special digestion methods (Annex A) and precision data (Annex B) lie outside it — we know only their titles from the table of contents, so we do not give volumes, solution concentrations, digestion conditions or the frequency of checks.
Method principle
The method is based on measuring light emission by an optical spectroscopic technique (clause 4). The sample is nebulized and the aerosol produced is transported to the plasma torch, where excitation takes place. The radio-frequency inductively coupled plasma produces characteristic emission spectra; the spectra are dispersed by a grating spectrometer and the line intensities are measured by the detector(s). The signals are processed and the measurement is controlled by a computer system.
A suitable background correction technique is used to compensate for variable background contributions in the determination of trace elements. Table 1 of the standard gives separate limits of quantification for radial and axial viewing of the plasma.
Applications
- Waste water — one of the reference methods for many metals (Journal of Laws 2019, item 1311, Annex 12)
- Monitoring of surface and ground waters — e.g. arsenic, zinc, copper (Journal of Laws 2021, item 1576, Annex 8)
- Drinking, raw, ground and surface water — dissolved elements, elements bound to particles and total content (clause 1)
- Digests of water, sludges and sediments (e.g. ISO 15587-1, ISO 15587-2)
Key parameters
| Parameter | Value |
|---|---|
| Elements determined | 35 (Al, Sb, As, Ba, Be, Bi, B, Cd, Ca, Cr, Co, Cu, Ga, In, Fe, Pb, Li, Mg, Mn, Mo, Ni, P, K, Se, Si, Ag, Na, Sr, S, Sn, Ti, W, V, Zn, Zr) |
| Forms | dissolved, bound to particles, total (after digestion or as the sum of the two fractions) |
| Suspended solids in waste water | below 2 g/l (clause 1) |
| Limits of quantification | depending on the element, line and plasma viewing — Table 1, e.g. Cd 214.441 nm about 1 µg/l (radial) |
| Definitions | limit of detection 3 s₀, limit of quantification 9 s₀ (3.10–3.11) |
| Correction | a suitable background correction technique (clause 4); spectral interferences at the recommended lines — Table 1 |
Standard
- Standard number
- PN-EN ISO 11885:2009
- Title (PL)
- Jakość wody — Oznaczanie wybranych pierwiastków metodą optycznej spektrometrii emisyjnej z plazmą wzbudzoną indukcyjnie (ICP-OES)
- Title (EN)
- Water quality — Determination of selected elements by inductively coupled plasma optical emission spectrometry (ICP-OES)
Step-by-step procedure
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Sampling and preservation
According to ISO 5667-1 and ISO 5667-3 (normative references) and clause 9 of the standard, which lies outside the available text.
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Choice of form
Dissolved elements, elements bound to particles or total; total content — determination in the unfiltered sample after digestion or the sum of the dissolved and particulate fractions (3.26).
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Digestion — when needed
E.g. according to ISO 15587-1 (aqua regia) or ISO 15587-2 (nitric acid); special digestion methods — informative Annex A (outside the available text).
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Choice of lines and instrument set-up
Recommended wavelengths and spectral interferences — Table 1; the plasma viewing mode (radial or axial) affects the achievable limit of quantification.
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Calibration
Calibration solutions and calibration blank; the calibration is checked with an independently prepared calibration check solution, and instrument drift with the instrument performance check solution (3.4–3.8).
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Measurement
Nebulization of the test sample solution, excitation in the plasma, measurement of line intensities with background correction (clause 4).
-
Limits of detection and quantification
From the standard deviation s₀ of the results of at least 3 measurements of the reagent blank solution: limit of detection 3 s₀, limit of quantification 9 s₀ (3.10–3.11).
Required equipment and apparatus
| Equipment | Example | Indicative price |
|---|---|---|
| ICP-OES spectrometer | radio-frequency inductively coupled plasma, grating spectrometer, detector(s), computer control, background correction (clause 4); radial or axial viewing (Table 1) | — |
| Sample introduction system | nebulizer producing an aerosol transported to the plasma torch (clause 4) | — |
| Digestion equipment | for total content — e.g. according to ISO 15587-1 (aqua regia) or ISO 15587-2 (nitric acid) | — |
Reagents, media and consumables
| Reagent | CAS | Details |
|---|---|---|
| Water | — | for analytical laboratory use according to ISO 3696 (normative reference of the standard) |
| Stock solutions | — | with accurately known analyte concentration, prepared from chemicals of appropriate purity — reference materials within the meaning of ISO Guide 30 (3.23) |
| Calibration solutions and calibration blank | — | solutions for calibration prepared from stock solutions or a certified standard; the calibration blank is prepared in the same way but without the analyte (3.4–3.5) |
| Calibration check solution | — | of known composition, within the range of the calibration solutions, prepared independently (3.6) |
| Instrument performance check solution | — | for determining and controlling the instrument drift for the relevant analytes (3.8) |
| Reagent blank solution | — | solvent with the same amounts of reagents as the test sample solution, same final volume; s₀ is calculated from it (3.10, 3.14) |
Health and safety (OHS)
- The standard states that the tests are to be carried out by suitably trained staff and that safety practices and compliance with national regulations are the responsibility of the user
- Handle digestion acids and solutions of toxic elements according to the safety data sheets
Frequently asked questions
Which standard describes this test?
The test is performed according to PN-EN ISO 11885:2009 — “Water quality — Determination of selected elements by inductively coupled plasma optical emission spectrometry (ICP-OES)”.
How does this method work?
The method is based on measuring light emission by an optical spectroscopic technique (clause 4). The sample is nebulized and the aerosol produced is transported to the plasma torch, where excitation takes place.
What is the measuring range and accuracy?
Elements determined: 35 (Al, Sb, As, Ba, Be, Bi, B, Cd, Ca, Cr, Co, Cu, Ga, In, Fe, Pb, Li, Mg, Mn, Mo, Ni, P, K, Se, Si, Ag, Na, Sr, S, Sn, Ti, W, V, Zn, Zr); Forms: dissolved, bound to particles, total (after digestion or as the sum of the two fractions); Suspended solids in waste water: below 2 g/l (clause 1); Limits of quantification: depending on the element, line and plasma viewing — Table 1, e.g. Cd 214.441 nm about 1 µg/l (radial).
How long does the test take?
The procedure comprises 7 steps. The standard does not give a duration for every stage — the laboratory's own procedure decides.
What equipment is required?
ICP-OES spectrometer, Sample introduction system, Digestion equipment.
Where is this test used?
Waste water — one of the reference methods for many metals (Journal of Laws 2019, item 1311, Annex 12); Monitoring of surface and ground waters — e.g. arsenic, zinc, copper (Journal of Laws 2021, item 1576, Annex 8); Drinking, raw, ground and surface water — dissolved elements, elements bound to particles and total content (clause 1); Digests of water, sludges and sediments (e.g. ISO 15587-1, ISO 15587-2).
What safety precautions apply?
The standard states that the tests are to be carried out by suitably trained staff and that safety practices and compliance with national regulations are the responsibility of the user; Handle digestion acids and solutions of toxic elements according to the safety data sheets.
Which laboratory can perform this test?
The test is performed by laboratories accredited to ISO/IEC 17025. On LabCoda you can find them by the standard number PN-EN ISO 11885.