Standards Development

Scope

This document specifies a test with which in situ available concentrations of inorganic substances (such as heavy metals, arsenic and phosphorus) and organic substances in soil and soil-like materials can be simulated under forced aerobic and anaerobic conditions. The toxicity can then be estimated based on these available concentrations.

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 and ISO 17616.

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 substances and apolar, hydrophobic organic substances (HOCs). In the latter case, mechanisms of release (e.g. particle-bound or dissolved organic carbonbound) 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 eluate obtained 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 outlined in Clause 4.

Purpose

In various countries, tests have been developed to characterize and assess the substances which can be released from materials. The release of soluble substances upon contact with water is regarded as a main mechanism of release, which results in a potential risk to the environment during the use or disposal of materials. The intent of these tests is to identify the leaching properties of materials. The complexity of the leaching process makes simplifications necessary. Not all of the relevant aspects of leaching behaviour can be addressed in one standard.

The test procedure proposed belongs to category “Basic characterization” tests.

“Basic characterization” tests are used to obtain information on the short-term and long-term leaching behaviour and characteristic properties of materials.

For large amounts of soil and soil-like materials a new beneficial destination is necessary. Examples of beneficial destination are elevation of new building location or land, dikes, improving lakes and harbours. The new use should not cause environmental risks, especially if heavy metals are present in the material.

This proposed test procedure specifies a test with which in situ available concentrations of inorganic substances (such as heavy metals, arsenic and phosphorus) and organic substances in soil and soil-like materials can be simulated under forced aerobic and anaerobic conditions. The toxicity can then be estimated based on these available concentrations.