Aerobic and anaerobic transformation in soil
OECD 307, Regulation (EC) No 440/2008, C.23
Soil samples are treated with the test substance and incubated in the dark in biometer-type flasks or in flow-through systems under controlled laboratory conditions. After appropriate time intervals, soil samples are extracted and analysed for the parent substance and for transformation products. Volatile products are also collected for analysis using appropriate absorption devices. Using 14C-labelled material, the various mineralisation rates of the test substance can be measured by trapping evolved 14CO2 and a mass balance, including the formation of soil bound residues, can be established.
Aerobic and anaerobe transformation in aquatic sediment systems
OECD 308, Regulation (EC) No 440/2008, C.24
The aim of the study is to measure the transformation and/or mineralisation rate of the test substance and/or its transformation products in aquatic sediment systems, the identification and quantification of transformation products and phase distribution including a mass balance (when labelled test substance is used). For this, two aerobic and two anaerobic sediments are used. The test duration usually is 100 days.
Aerobic mineralisation in surface water - simulation biodegradation test
OECD 309, Regulation (EC) No 440/2008, C.25
Determination of the time course of biodegradation of a test substance at environmental realistic concentrations (< 1 µg/l to 100 µg/l) in a shake flask batch test with natural surface water (fresh, brackish or marine). The low concentrations ensure that the biodegradation kinetics obtained in the test reflect those expected in the environment. The test flasks are incubated in the dark at ambient temperature while shaking under aerobic conditions in at least two levels. At appropriate time intervals either the residual 14C or the residual concentration of test substance are measured. The test duration usually is up to 60 days.
The laboratory of Hydrotox does not maintain a radionuclide laboratory. Simulation tests are carried out in co-operation laboratories.