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.