ISO/TC 190/SC 3/WG 1 - Inorganic analysis

This document specifies the determination of Cr(VI) in solid waste material and soil by alkaline digestion and ion chromatography with spectrophotometric detection. This method can be used to determine Cr(VI)-mass fractions in solids higher than 0,1 mg/kg. NOTE In case of reducing or oxidising waste matrix no valid Cr(VI) content can be reported.

This document specifies two methods for digestion of soil, treated biowaste, sludge and waste by the use of an aqua regia digestion. Digestion with aqua regia will not necessarily accomplish total decomposition of the sample. The extracted analyte concentrations may not necessarily reflect the total content in the sample but represent the aqua regia soluble metals under the condition of this test procedure. It is generally agreed that for environmental analysis purposes, the results are fit for the intended purpose to protect the environment. This document is applicable for the following elements: Aluminium (Al), antimony (Sb), arsenic (As), barium (Ba), beryllium (Be), boron (B), cadmium (Cd), calcium (Ca), chromium (Cr), cobalt (Co), copper (Cu), iron (Fe), lead (Pb), magnesium (Mg), manganese (Mn), mercury (Hg), molybdenum (Mo), nickel (Ni), phosphorus (P), potassium (K), selenium (Se), silver (Ag), sodium (Na), strontium (Sr), sulfur (S), tellurium (Te), thallium (Tl), tin (Sn), titanium (Ti), vanadium (V), and zinc (Zn). This document can also be applied for the digestion of other elements, provided the user has verified the applicability.

ISO/TR 19588:2017 provides background information on the various International (ISO), American (ASTM, EPA), and European (CEN) cyanide methods for soils, waters, effluents and wastes. It gives guidance on how to carry out fit for purpose analysis of various forms of cyanide in environmental samples, the significance of the results, how to minimize interference effects and the preservation of samples. Some information is also provided on other national and international cyanide methods.

ISO 14869-3:2017 specifies a method for microwave-assisted dissolution of soil samples for determination of total element contents of Al, As, Ba, Ca, Cd, Co, Cr, Cs, Cu, Fe, Hg, K, Li, Mg, Mn, Na, Ni, P, Pb, S, Se, Sb, Sr, Tl, V, Zn using an acid mixture of nitric acid (HNO3), hydrofluoric acid (HF) and hydrochloric acid (HCl). This method is applicable to all types of soil and soil material. The main field of application is geological and pedological survey. The acid mixture is suitable for total dissolution of element contents in soil (major, minor and trace), but some refractory compounds such as SiO2, TiO2, spinel, Al2O3 or other compounds may remain as a residue. In such a case, the use of alkaline fusion, following ISO 14869‑2, is recommended to determine the true total element content. NOTE 1 In environmental studies, usually, aqua regia extraction is applied using ISO 12914 or ISO 11466. Solutions produced by the microwave method are suitable for analysis, for example, by using atomic absorption spectrometry (FAAS, HGAAS, CVAAS, GFAAS), inductively coupled plasma optical emission spectrometry (ICP-OES) and inductively coupled plasma mass spectrometry (ICP-MS). NOTE 2 Due to the presence of chloride in the digestion solution, limitations for the application of some analytical techniques can occur.

ISO 17586:2016 specifies a method of extracting trace elements from soil at approximately pH 0,5 using a dilute nitric acid solution. Using this method the potential environmental available trace elements as defined in ISO 17402 is extracted. The method is applicable for all soils and soil like materials.

ISO 14388-1:2014 provides a general introduction to acid sulfate soils and the approaches that can be used to measure the various components of this special group of soils and their potential to produce acidity. It provides a compilation of the test methods, identification and definitions of the symbols, terms, and acronyms used in this series of ISO 14388. While part of the decision-making process can involve the analysis of prepared wet or dry samples, ISO 14388-1:2014 specifically outlines the procedures that are involved for preparing and analysing dried samples. ISO 14388-1:2014 also provides a procedure for pre-treating acid sulfate soil following sampling, prior to their analysis as dried sample using appropriate methods of test. The procedure includes the handling of samples before delivery to the laboratory, and the drying, grinding, and storage of samples. The standard also provides a procedure for archiving a sample after analysis. ISO 14388-1:2014 provides an acid-base accounting method to calculate the net acid-producing potential of acid sulfate soil materials by individually assessing the acid-producing capacity due to oxidation of inorganic sulfides, the existing acidity, and the effective acid-consuming capacity using results obtained in ISO 14388-2 and ISO 14388-3.

ISO 14388-3:2014 specifies a suite of methods used to determine net acidity in acid sulfate soils. ISO 14388-3:2014 specifies a method for the determination of pH in a 1 mol/l potassium chloride soil suspension (pHKCl) and where required, titratable actual acidity (TAA). Following this, potassium chloride extractable sulfur (SKCl), calcium (CaKCl) and magnesium (MgKCl) are determined. On a separate test portion, following digestion with 30 % hydrogen peroxide, peroxide pH (pHOX), titratable peroxide acidity (TPA) and excess acid neutralizing capacity (ANCE) are determined. Following this, peroxide sulfur (SP), calcium (CaP) and magnesium (MgP) are determined. On samples where jarosite is present, or where pHKCl is RAS) is determined on the soil residue remaining after peroxide digestion. Titratable sulfidic acidity (TSA), reacted calcium (CaA), reacted magnesium (MgA) and peroxide oxidizable sulfur (SPOS) are then determined by difference. For peat samples containing substantial levels of organic sulfur, the SPOCAS suite is generally unsuitable for estimating sulfide content, and the chromium reducible suite of procedures should be used instead.

ISO 14388-2:2014 specifies a suite of methods used to determine the net acidity in acid sulfate soils. ISO 14388-2:2014 specifies a method for measuring chromium reducible sulfur (SCR) by iodimetric titration of distilled hydrogen sulfide trapped as zinc sulfide, following acidic chromous chloride digestion. This method determines inorganic sulfides (e.g. pyrite, marcasite, greigite, mackinawite) and elemental sulfur in acid sulfate soil without interferences from organic sulfur and oxidized forms of sulfur such as sulfate. On a separate test portion of soil, the pH in a 1 mol/l KCl soil suspension (pHKCl) is determined. When pHKCl is KCl), calcium (CaKCl), and magnesium (MgKCl) can also be determined. Where jarosite is identified in the soil (or where pHKCl is NAS) is determined by the difference between hydrochloric acid extractable sulfur (SHCl) and potassium chloride extractable sulfur. On samples where pHKCl is IN) by combustion furnace, or ANCBT (ANC measured by back-titration of acid remaining following an acid digest).

ISO 16729:2013 specifies a method for microwave digestion of sludge, treated biowaste and soil using nitric acid. This method is applicable for microwave-assisted nitric acid digestion of sludge, treated biowaste and soils for the following elements: Aluminium (Al), antimony (Sb), arsenic (As), barium (Ba), beryllium (Be), bismuth (Bi), boron (B), cadmium (Cd), calcium (Ca), cerium (Ce), cesium (Cs), chromium (Cr), cobalt (Co), copper (Cu), dysprosium (Dy), erbium (Er), europium (Eu), gadolinium (Gd), gallium (Ga), germanium (Ge), gold (Au), hafnium (Hf), holmium (Ho), indium (In), iridium (Ir), iron (Fe), lanthanum (La), lead (Pb), lithium (Li), lutetium (Lu), magnesium (Mg), manganese (Mn), mercury (Hg), molybdenum (Mo), neodymium (Nd), nickel (Ni), palladium (Pd), phosphorus (P), platinum (Pt), potassium (K), praseodymium (Pr), rubidium (Rb), rhenium (Re), rhodium (Rh), ruthenium (Ru), samarium (Sm), scandium (Sc), selenium (Se), silicon (Si), sodium (Na), strontium (Sr), sulfur (S), tellurium (Te), terbium (Tb), thallium (Tl), thorium (Th), thulium (Tm), tin (Sn), titanium (Ti), tungsten (W), uranium (U), vanadium (V), ytterbium (Yb), yttrium (Y), zinc (Zn) and zirconium (Zr). ISO 16729:2013 may also be applicable for the digestion of other elements. Digestion with nitric acid will not necessarily accomplish total decomposition of the sample. The extracted analyte concentrations may not necessarily reflect the total content in the sample.

ISO/TS 16965:2013 specifies a method for the determination of the following elements in aqua regia or nitric acid digests or other extraction solutions of sludge, treated biowaste and soil: Aluminium (Al), antimony (Sb), arsenic (As), barium (Ba), beryllium (Be), bismuth (Bi), boron (B), cadmium (Cd), calcium (Ca), cerium (Ce), cesium (Cs), chromium (Cr), cobalt (Co), copper (Cu), dysprosium (Dy), erbium (Er), europium (Eu), gadolinium (Gd), gallium (Ga), germanium (Ge), gold (Au), hafnium (Hf), holmium (Ho), indium (In), iridium (Ir), iron (Fe), lanthanum (La), lead (Pb), lithium (Li), lutetium (Lu), magnesium (Mg), manganese (Mn), mercury (Hg), molybdenum (Mo), neodymium (Nd), nickel (Ni), palladium (Pd), phosphorus (P), platinum (Pt), potassium (K), praseodymium (Pr), rhenium (Re), rhodium (Rh), rubidium (Rb), ruthenium (Ru), samarium (Sm), scandium (Sc), selenium (Se), silicon (Si), silver (Ag), sodium (Na), strontium (Sr), sulfur (S), tellurium (Te), terbium (Tb), thallium (Tl), thorium (Th), thulium (Tm), tin (Sn), titanium (Ti), tungsten (W), uranium (U), vanadium (V), ytterbium(Yb), yttrium (Y), zinc (Zn) and zirconium (Zr). The working range depends on the matrix and the interferences encountered. The limit of detection is between 0,1 mg/kg dry matter and 2,0 mg/kg dry matter for most elements.

ISO/TS 16727:2013 specifies a method for the determination of mercury in aqua regia or nitric acid digests of sludge, treated biowaste and soil, obtained according to ISO 11466 or ISO 16729 using cold vapour atomic fluorescence spectrometry. The lower working range limit is 0,003 mg/kg (dry matter).

ISO 17380:2013 specifies a method for the photometric determination of the total cyanide and easily-liberatable cyanide content in soil using automated distillation/continuous-flow analysis. ISO 17380:2013 applies to all types of soil with cyanide contents above 1 mg/kg on the basis of dry matter, expressed as cyanide ion.

ISO 19730:2008 specifies a method of extracting trace elements from soil using a 1 mol/l NH4NO3 solution.

ISO 20280:2007 specifies methods for the determination of arsenic, antimony and selenium, in an aqua regia extract of soil obtained in accordance with ISO 11466, by electrothermal or hydride-generation atomic absorption spectrometry.

ISO 14256-2:2005 describes an automated method for the determination of nitrate, nitrite and ammonium in a 1 mol/l potassium chloride extract of field-moist soil samples. ISO 14256-2:2005 is applicable to all types of soils homogenized by suitable methods.

ISO 16772:2004 specifies a method for the determination of mercury in an aqua regia extract of soil, obtained in accordance with ISO 11464 and ISO 11466, using cold-vapour atomic absorption spectrometry or cold-vapour atomic fluorescence spectrometry. The limit of determination of the method is at least 0,1 mg/kg.

ISO/TS 14256-1:2003 describes a method for the determination of nitrate, nitrite and ammonium in a 1 mol/l potassium chloride extract of field-moist soil samples. ISO/TS 14256-1:2003 is applicable to all types of soils homogenized by suitable methods.

ISO 14869-2:2002 specifies a method for the dissolution of total contents for the following elements in soils: Na, K, Mg, Ca, Ti, Mn, Fe, Al, Si This list is not exhaustive, and other elements are applicable for determination provided: they are not lost during the fusion process, w > (3d · V/m). where w is the mass content of the element, expressed in milligrams per kilogram soil, d is the detection limit, in milligrams per litre, for the element and analytical method considered, 3 is a conventional factor, V is the adjusted volume, in litres, of the final solution containing the dissolved sample, and m is the mass of the test portion, in kilograms, the determination is not adversely affected by the high salt concentration in the resultant solution. The flux proposed in this method is suitable for a wide range of materials, among which soil samples are relatively easy to deal with.

Describes a procedure using dry combustion for the determinationof total sulfur in soil samples. It is important to note that high temperature combustion methods might not determine total sulfur, only combustible sulfur. The difference between total and combustible sulfur is usually negligible in soils.

Specifies a method for the determination of the total nitrogen (ammonium-N, nitrate-N, nitrite-N and organic N) content of a soil. Nitrogen in N-N-linkages, N-O-linkages and some heterocyclics (especially pyridine) is only partially determined. Applicable to all types of soils.

Specifies a method for the determination of the total carbon content in soil after dry combustion. The organic carbon content is calculated from this content after correcting for carbonates present in the sample. If carbonates are removed beforehand, the organic carbon content is measured directly. Applicable to all types of air-dried soil samples.

Specifies an extraction method and analytical conditions to determine the content of soil phosphorus soluble in sodium hydrogen carbonate solution. Lays down colour development at room temperature and after heating to a high temperature. Applicable to all types of soils.

ISO/TS 17073.2013 specifies the determination of trace elements in aqua regia or nitric acid digests or other extraction procedures of sludge, treated biowaste and soil, using atomic absorption spectrometry with electrothermal atomization in a graphite furnace. The method is applicable for the determination of the following elements: Arsenic (As), cadmium (Cd), cobalt (Co), lead (Pb), antimony (Sb), thallium (Tl), vanadium (V). This method may be applied to other elements. The lower working range is approximately 0,01 mg/kg to 0,001 mg/kg, depending on the element to be determined.

ISO 12914:2012 specifies a method for microwave-assisted extraction of elements from samples using aqua regia as the extraction solution for the determination of elements. This method is applicable to all types of soil and soil material.

ISO 15192:2010 specifies a method for the determination of Cr(VI) in solid waste material and soil by alkaline digestion and ion chromatography with spectrophotometric detection. This method can be used to determine Cr(VI) mass fractions in solids greater than 0,1 mg/kg.

ISO 22036:2008 describes the determination of trace elements in digests or extraction solutions from soil by inductively coupled plasma - atomic emission spectrometry (ICP-AES) for 34 elements. This multi-element determination method is applicable to soil extracts obtained with aqua regia in accordance with ISO 11466, with DTPA in accordance with ISO 14870 or other weak extractants, or soil extracts for the determination of total element contents using the acid digestion method of ISO 14869-1 or the fusion method of ISO 14869-2. The choice of calibration method depends on the extractant and can be adapted to the extractant concentration.

ISO 20279:2005 specifies methods for extraction of thallium from soil by nitric acid and hydrogen peroxide and its determination in the extract by electrothermal atomic absorption spectrometry (ETAAS).

Specifies a method for the extraction, with aqua regia, of trace elements from soils and similar materials containing less than about 20 % (m/m) organic carbon. Materials containing more than about 20 % (m/m) organic carbon will require treatment with additional nitric acid. The resulting solution is suitable for the determination of trace elements using appropriate atomic spectrometric techniques.