China recently drafted 2 GB/T (national recommended) standards focusing on biodegrability which were released for public consultation on 5 Nov, 2013, namely the “Chemicals - Inherent biodegradability in soil test” and the “Chemicals - Aerobic mineralization in surface water - Simulation biodegradation test”. Feedback should be sent to the CRC-MEP before 25 Nov.
The “Chemicals - Inherent biodegradability in soil test” is identical in technical contents with OECD No.304A: 1989. It is designed for the evaluation of the inherent biodegradability of a chemical in soil through the determination of the mineralization rate of the 14C-labelled chemical in soil. The method is applicable to volatile or non-volatile, soluble or insoluble chemicals which are not inhibitory to micro-organisms.
The “Chemicals - Aerobic mineralization in surface water - Simulation biodegradation test” adopts OECD No.309: 2004. It measure the rate of biodegradation of a test substance at low concentration in aerobic natural water. Observations are quantified and expressed as kinetic rate expressions. This simulation test is applicable to non-volatile or slightly volatile organic substances tested at low concentrations.
The testing data produced according by these two tests will be important for chemical hazard evaluation, risk assessment and classification.
