Standardized methods for anaerobic biodegradability testing

The European Community Directive 67/548/EEC (adopted in 1967), Annex V, contains about 85 testing methods, legally binding for all EU-Member States. They are regularly updated, or new methods are introduced in a formal procedure. Until 2002, no anaerobic biodegradability testing methods have been explicitly included either in the EU Directive 67/548/EEC or in the OECD-Guidelines adopted. However, a ‘hidden’ EU-document with a testing scheme exists which recommends when anaerobic testing may be applied, without specifying in detail which legally binding method is to be used.In order to give an impression of the spectrum available, anaerobic test schemes proposed by ASTM, CEN, DIN, ISO, ECETOC, and OECD, are classified according to temperature, test environment, test purposes, and the equipment used.Some problems with the equipment and the methodology such as permeation phenomena, reproducibility, and the medium composition are addressed. With this, the difficulty to reach a satisfying carbon balance can be better understood. Finally, some recommendations are given on how to improve knowledge on the test equipment and the test procedure.