ISO/NP 8259

Soil quality — Bioaccessibility of organic and inorganic pollutants from contaminated soil and soil-like material

Scope

This document specifies a method for testing the availability for absorption or bioaccessibility of substances from contaminated soils and soil-like materials. Only those substances can be investigated that have a sufficiently low vapour pressure and for which larger losses cannot occur under the test conditions in accordance with this standard. Furthermore, suitable analysis methods shall be used for extraction and detection of substances and/or elements from complex digestion assays.
In the test system presented here, the mobilisation of organic and inorganic pollutants from contaminated particles is tested in a physiologically close-to-realistic manner under standardised conditions with the aid of artificial digestive juices (gastric juice and intestinal juice). In terms of their main components, their composition corresponds approximately to the average composition of natural digestive juices of humans in the case of stimulated secretion, as occurs during the intake of foodstuffs. The treatment duration of the samples with gastric juice of 2 h corresponds to the average residence times of foodstuffs in the stomach. In contrast, the treatment duration with intestinal juice of 3 h is based on the residence time of foodstuff components in the upper section of the small intestine, which is the main site of absorption.