scope:

This document specifies a method for testing the bioaccessibility of substances from contaminated soils and soil-like materials. The method is not applicable for volatile contaminants. 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 dissolution of organic and inorganic pollutants from contaminated particles through the gastrointestinal tract 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.

NOTE 1 Bioaccessibility can be used to approximate oral bioavailability.

NOTE 2 The test has been validated in-vivo for arsenic, lead, cadmium, chromium, nickel and mercury by animal testing. Polycyclic aromatic hydrocarbons (PAHs) including Benzo[a]pyrene (BaP) were also used in in vivo animal testing. An inter-laboratory trial was carried out using arsenic, lead, cadmium and antimony as well as polycyclic aromatic hydrocarbons (PAHs), polychlorinated biphenyls (PCBs) and trinitrotoluene.

NOTE 3 Metals include also arsenic and other metalloids.