Table 2.

Inherent biodegradability tests

Test	Method	Test principle	Remarks
Modified SCAS Test (Semi-continuous activated sludge)	OECD 302 A (1981), ISO 9887 (1992)	Semi-static, aerobic test system, fill- and draw method, measurement of DOC removal, test period up to 26 weeks	Non-volatile, water-soluble compounds, pre-adaptation and specific analysis to determine primary biodegradation possible
Zahn-Wellens/EMPA Test	OECD 302 B (1992), ISO 9888 (1999)	Static, aerobic test system, high test compound, and inoculum concentration, measurement of DOC removal	Non-volatile, water-soluble compounds
Modified MITI (II) Test	OECD 302 C (1981)	Static, aerobic test system, comparable to OECD 302 B (1992) but a specially prepared inoculum is required	Non-volatile, water-soluble compounds
Inherent biodegradability in soil	OECD 304 A (1981)	Static, aerobic test, addition of 14C labeled test compound, determination of 14CO2	Closed system; volatile/non-volatile and soluble/non-soluble compounds