ISO/TC 190/SC 7/WG 6 - Transfer and mobility of components

This document specifies an extraction method to determine the bioavailable (potential and environmental available) fraction and the non-bioavailable fraction of a contaminant in soil using a "receiver phase" for an organic contaminant with strong sorbing or complexing properties, for example, Tenax®[1] or cyclodextrin, respectively. NOTE 1 The bioavailable fraction is defined in ISO 17402 as environmental bioavailability. The method is applicable for non-polar organic contaminants with an aqueous solubility of NOTE 2 The method is theoretically applicable to non-polar organic contaminants with an aqueous solubility of 1 000 mg/l. The method has been often applied for compounds with a much lower solubility (Kow > 3) and less for compounds with a higher solubility. The applicability is therefore defined for compounds with an aqueous solubility of [1] Tenax® is an example of a suitable product available commercially. This information is given for the convenience of users of this document and does not constitute an endorsement by ISO of this product.

This document provides guidance on the use of chemical methods establishing the bioavailability of trace elements in soil and soil-like materials and to stimulate the use of bioavailability in assessments. The methods themselves are not subject of this document.

This document specifies a test to obtain information on the short- and long-term leaching behaviour and characteristic properties of materials. The document has been developed to measure the pH-dependent release of inorganic and organic substances from soil and soil-like material as well as to produce eluates for subsequent ecotoxicological testing. For ecotoxicological testing, see ISO 15799 and ISO 17616. The equilibrium condition, as defined in this document, is established by the addition of predetermined amounts of acid or base to reach desired final pH values. NOTE 1 Volatile organic substances include the low molecular weight substances in mixtures such as mineral oil. NOTE 2 It is not always possible to optimize test conditions simultaneously for inorganic and organic substances and optimum test conditions can also vary between different groups of organic substances. Test requirements for organic substances are generally more stringent than those for inorganic substances. The test conditions suitable for measuring the release of organic substances will generally also be applicable to inorganic substances. NOTE 3 Within the category of organic substances, a significant difference in behaviour exists between the more polar, relatively water-soluble compounds and apolar, hydrophobic organic substances (HOCs). In the latter case, mechanisms of release (e.g. particle-bound or dissolved organic carbon-bound) can be more crucial as well as sorption losses of soluble HOCs on different materials with which they come in contact (e.g. bottles, filters). The test and the results should be used for leaching of organic substances only with thorough consideration of the specific properties of the substances in question and the associated potential problems. NOTE 4 For ecotoxicological testing, eluates representing the release of both inorganic and organic substances are needed. In this document, ecotoxicological testing is meant to include genotoxicological testing. The test method produces eluates, which can subsequently be characterized by physical, chemical and ecotoxicological methods in accordance with existing standard methods. The test is not suitable for substances that are volatile under ambient conditions. For the purposes of ecotoxicological tests, the relevant pH range (see 8.2) will usually be pH 5 to pH 9. This test is mainly aimed at being used for routine and control purposes, and it cannot be used alone to describe all leaching properties of a soil. Additional leaching tests are needed for that extended goal. This document does not address issues related to health and safety. It only determines the leaching properties outlined in Clause 5.

This document specifies a test, which is aimed at determining the leaching behaviour of inorganic and organic substances from a soil and soil-like materials. The method is a once-through up-flow percolation test under standardized conditions of flow rate. The material is leached under dynamic hydraulic conditions. The document has been developed to measure the release of inorganic and organic substances from soil and soil-like material as well as to produce eluates for subsequent ecotoxicological testing. For ecotoxicological testing, see ISO 15799[6] and ISO 17616[7]. The test results enable the distinction between different release patterns, for instance wash-out and release under the influence of interaction with the matrix, when approaching local equilibrium between material and leachant. This test method produces eluates, which can subsequently be characterized by physical, chemical and ecotoxicological methods in accordance with existing standard methods. The results of eluate analysis are presented as a function of the liquid/solid (L/S) ratio. The test is not suitable for substances that are volatile under ambient conditions. NOTE 1 Volatile organic substances include the low-molecular-weight substances in mixtures such as mineral oil. NOTE 2 It is not always possible to optimize test conditions simultaneously for inorganic and organic substances and optimum test conditions can also vary between different groups of organic substances. Test requirements for organic substances are generally more stringent than those for inorganic substances. The test conditions suitable for measuring the release of organic substances will generally also be applicable to inorganic substances. NOTE 3 Within the category of organic substances, a significant difference in behaviour exists between the more polar, relatively water-soluble compounds and apolar, hydrophobic organic substances (HOCs). In the latter case, mechanisms of release (e.g. particle-bound or dissolved organic carbon-bound) can be more crucial as well as sorption losses of soluble HOCs on different materials with which they come in contact (e.g. bottles, filters). The test and the results should be used for leaching of organic substances only with thorough consideration of the specific properties of the substances in question and the associated potential problems. NOTE 4 For ecotoxicological testing, eluates representing the release of both inorganic and organic substances are needed. In this document, ecotoxicological testing is also meant to include genotoxicological testing. NOTE 5 The test is generally not suitable for soils with hydraulic conductivities below 10−8 m/s (see also Annex B). It can be difficult to maintain the designated flow rate already in the range of saturated hydraulic conductivity between 10−7 m/s and 10−8 m/s. The application of this test method alone is not sufficient for the determination of the leaching behaviour of a material under specified conditions different to those from the test procedure, since this generally requires the application of several test methods, behavioural modelling and model validation. This document does not address issues related to health and safety. It only determines the leaching properties as outlined in Clause 4.

This document specifies a test providing information on leaching of soil and soil materials under the experimental conditions specified hereafter, and particularly at a liquid to solid ratio of 10 l/kg dry matter. The document has been developed to measure the release of inorganic and organic substances from soil and soil-like material as well as to produce eluates for subsequent ecotoxicological testing. For ecotoxicological testing, see ISO 15799[6] and ISO 17616[7]. NOTE 1 Volatile organic substances include the low-molecular-weight substances in mixtures such as mineral oil. NOTE 2 It is not always possible to optimize test conditions simultaneously for inorganic and organic substances and optimum test conditions can also vary between different groups of organic substances. Test requirements for organic substances are generally more stringent than those for inorganic substances. The test conditions suitable for measuring the release of organic substances will generally also be applicable to inorganic substances. NOTE 3 Within the category of organic substances, a significant difference in behaviour exists between the more polar, relatively water-soluble compounds and apolar, hydrophobic organic substances (HOCs). In the latter case, mechanisms of release (e.g. particle-bound or dissolved organic carbon-bound) can be more crucial as well as sorption losses of soluble HOCs on different materials with which they come in contact (e.g. bottles, filters). The test and the results should be used for leaching of organic substances only with thorough consideration of the specific properties of the substances in question and the associated potential problems. NOTE 4 For ecotoxicological testing, eluates representing the release of both inorganic and organic substances are needed. In this document, ecotoxicological testing is also meant to include genotoxicological testing. This test method produces eluates, which can subsequently be characterized by physical, chemical and ecotoxicological methods in accordance with existing standard methods. The test is not suitable for substances that are volatile under ambient conditions. This procedure is not applicable to materials with a dry-matter-content ratio lower than 33 %. This test is mainly aimed at being used for routine and control purposes, and it cannot be used alone to describe all leaching properties of a soil. Additional leaching tests are needed for that extended goal. This document does not address issues related to health and safety. It only determines the leaching properties as outlined in Clause 4.

This document specifies a test providing information on leaching of soil and soil-like materials under the experimental conditions specified hereafter, and particularly at a liquid to solid ratio of 2 l/kg dry matter. The document has been developed to measure the release of inorganic and organic substances from soil and soil-like material as well as to produce eluates for subsequent ecotoxicological testing. For ecotoxicological testing, see ISO 15799[6] and ISO 17616[7]. NOTE 1 Volatile organic substances include the low-molecular-weight substances in mixtures such as mineral oil. NOTE 2 It is not always possible to optimise test conditions simultaneously for inorganic and organic substances and optimum test conditions can also vary between different groups of organic substances. Test requirements for organic substances are generally more stringent than those for inorganic substances. The test conditions suitable for measuring the release of organic substances will generally also be applicable to inorganic substances. NOTE 3 Within the category of organic substances, a significant difference in behaviour exists between the more polar, relatively water-soluble compounds and apolar, hydrophobic organic substances (HOCs). In the latter case, mechanisms of release (e.g. particle-bound or dissolved organic carbon-bound) can be more crucial as well as sorption losses of soluble HOCs on different materials with which they come in contact (e.g. bottles, filters). The test and the results should be used for leaching of organic substances only with thorough consideration of the specific properties of the substances in question and the associated potential problems. NOTE 4 For ecotoxicological testing, eluates representing the release of both inorganic and organic substances are needed. In this document, ecotoxicological testing is also meant to include genotoxicological testing. This test method produces eluates, which can subsequently be characterized by physical, chemical and ecotoxicological methods in accordance with existing standard methods. The test is not suitable for substances that are volatile under ambient conditions. This procedure is not applicable to materials with a dry-matter-content ratio lower than 33 %. This test is mainly aimed at being used for routine and control purposes, and it cannot be used alone to describe all leaching properties of a soil. Additional leaching tests are needed for that extended goal. This document does not address issues related to health and safety. It only determines the leaching properties as outlined in Clause 4.

ISO 16198:2015 specifies the plant-based test, called biotest, which enables estimation of the environmental bioavailability of trace elements to plants either basically as the concentration in shoots and roots or in a more integrative way as the net uptake flux in plants.

ISO 12782-5:2012 specifies a procedure to determine the concentration of humic substances in aqueous samples. These samples may be obtained as such or as eluates from leaching procedures applied to soil or other materials. Other materials also include waste.The content of humic substances can be used as input in geochemical models.

ISO 12782-1:2012 specifies the determination of the content of "reactive" iron in the form of amorphous iron oxides and hydroxides in soil and other materials by extraction with ascorbic acid. Other materials also include waste. The content of "reactive" iron can be used as input in geochemical models to represent the content of amorphous iron (hydr)oxides.

ISO 12782-3:2012 specifies the determination of the content of "reactive" aluminium in the form of amorphous aluminium oxides and hydroxides in soil and other materials by extraction with ammonium oxalate/oxalic acid. Other materials also include waste. The content of "reactive" aluminium can be used as input in geochemical models.

ISO 12782-4:2012 specifies a procedure to determine the concentration of humic substances in soil or other materials. Other materials also include waste. The content of humic substances can be used as input in geochemical models.

ISO 12782-2:2012 specifies the determination of the content of "reactive" iron in the form of crystralline iron oxides and hydroxides in soil and other materials by extraction with dithionite. Other materials also include waste. The content of "reactive" iron can be used as input in geochemical models to represent the content of crystalline iron (hydr)oxides.

ISO 17402:2008 provides guidance for the selection and application of methods to assess bioavailability for the characterisation of contaminated soil and soil materials. ISO 17402:2008 does not give a selection of the best applicable methods, but specifies boundary conditions and principles of methods to be used and gives the minimal requirements for the development of methods. The results obtained from such methods can be used as an estimate of bioavailability in a risk-assessment approach. The contaminants considered in ISO 17402:2008 are metals, including metalloids, and organic contaminants, including organometal compounds. This International Standard is also applicable to metals originating from natural geological and pedological processes (natural pedo-geochemical content). ISO 17402:2008 can also be applied to sediments.

ISO 18772:2008 provides guidance on the appropriate use of leaching tests on soil and soil materials, in order to determine the leaching behaviour in the framework of impact assessment, or for compliance and comparison purposes, including information on the following: the choice of leaching tests, depending on the nature of the problem to be solved and the specific features of the different tests; the interpretation of the test results; the limitations of the tests. In this respect, it is important to keep in mind that leaching tests do not aim to simulate real field conditions, but are designed to address the contact between a solid and a liquid phase for different purposes that are described in ISO 18772:2008. ISO 18772:2008 only concerns natural, contaminated and agricultural soils and soil materials. Questions relating to the leaching of wastes are not covered by ISO 18772:2008. It also does not cover the subject of bioavailability of contaminants to living organisms, which is covered by ISO 17402.

ISO/TS 16751:2018 specifies an extraction method to determine the bioavailable (potential and environmental available) fraction and the non-bioavailable fraction of a contaminant in soil using a "receiver phase" for an organic contaminant with strong sorbing or complexing properties, for example, Tenax®[1] or cyclodextrin, respectively.

ISO/TS 21268-4:2007 specifies a test method to obtain information on the short- and long-term leaching behaviour and characteristic properties of materials. It applies to the determination of the influence of pH on the leachability of inorganic and organic constituents from soil and soil material, and the ecotoxicological effects of eluates with respect to microorganisms, fauna and flora. The test is not suitable for constituents that are volatile under ambient conditions. The test procedure specified in ISO/TS 21268-4:2007 produces eluates that are subsequently characterized by physical, chemical and ecotoxicological standard methods.

ISO/TS 21268-1:2007 specifies a test providing information on leaching of soil and soil materials under the experimental conditions specified hereafter, and particularly at a liquid to solid ratio of 2 l/kg dry matter. It applies to soil and soil material with a particle size less than or equal to 4 mm. ISO/TS 21268-1:2007 has been developed to measure the release of inorganic and organic constituents from soil and soil material and the ecotoxicological effects of eluates with respect to micro-organisms, fauna and flora. The test is not suitable for constituents that are volatile under ambient conditions. For ecotoxicological testing, see ISO 15799. The test procedure specified in ISO/TS 21268-1:2007 produces eluates, which are subsequently characterised by existing physical, chemical and ecotoxicological standard methods. This procedure is not applicable to materials with a dry-matter-content ratio lower than 33 %. This test is mainly aimed at being used for routine and control purposes, and it cannot be used alone to describe all leaching properties of a soil. Additional leaching tests are needed for that extended goal. ISO/TS 21268-1:2007 does not address issues related to health and safety. It only determines the leaching properties.

ISO/TS 21268-3:2007 specifies a test, which is aimed at determining the leaching behaviour of inorganic and organic constituents from a soil and soil material. The method is a once-through percolation test with water (0,001 mol/l CaCl2) under standardized conditions of flow rate. The material is leached under dynamic hydraulic conditions. The eluates obtained can be used to determine the ecological properties of the soil with respect to micro-organisms, flora and fauna. The test results enable the distinction between different release patterns, for instance wash-out and release under the influence of interaction with the matrix, when approaching local equilibrium between material and leachant. This test method produces eluates, which can subsequently be characterised by physical, chemical and ecotoxicological methods in accordance with existing standard methods. The results of eluate analysis are presented as a function of the liquid/solid ratio. The test is not suitable for species that are volatile under ambient conditions. The application of this test method alone is not sufficient for the determination of the leaching behaviour of a material under specified conditions different to those from the test procedure, since this generally requires the application of several test methods, behavioural modelling and model validation. ISO/TS 21268-3:2007 does not address issues related to health and safety. It only determines the leaching properties as outlined in Clause 4.

ISO/TS 21268-2:2007 specifies a test providing information on leaching of soil and soil materials under the experimental conditions specified hereafter, and particularly at a liquid to solid ratio of 10 l/kg dry matter. It applies to soil and soil material with a particle size less than or equal to 4 mm. ISO/TS 21268-2:2007 has been developed to measure the release of inorganic and organic constituents from soil and soil material and the ecotoxicological effects of eluates with respect to micro-organisms, fauna and flora. The test is not suitable for constituents that are volatile under ambient conditions. For ecotoxicological testing, see ISO 15799. The test procedure specified in ISO/TS 21268-2:2007 produces eluates, which are subsequently characterised by existing physical, chemical and ecotoxicological standard methods. This test is mainly aimed at being used for routine and control purposes, and it cannot be used alone to describe all leaching properties of a soil. Additional leaching tests are needed for that extended goal. ISO/TS 21268-2:2007 does not address issues related to health and safety. It only determines the leaching properties.