GB/T 19276.1-2026 Determination of the ultimate aerobic biodegradability of plastic materials in an aqueous medium—Part 1:Method by measuring the oxygen demand in a closed respirometer
GB/T 19276.1-2026 Determination of the ultimate aerobic biodegradability of plastic materials in an aqueous medium—Part 1:Method by measuring the oxygen demand in a closed respirometer
Basic Information
Scope
This document specifies a method for determining the aerobic biodegradability of materials, including plastics containing additives, by exposing the test materials to an aqueous culture solution prepared from activated sludge under test conditions and measuring the amount of oxygen consumed in a closed respirometer.
If untreated activated sludge is used as an inoculum, this test only simulates the biodegradation process in a natural aqueous environment; if mixed or pre-exposed inoculum is used, this method can be used to determine the potential biodegradation performance of the test materials.
The test conditions adopted in this document are not necessarily the optimal conditions for achieving maximum biodegradation performance, but this document is designed to determine the potential biodegradation capacity of materials or to represent the biodegradation performance of materials in natural environments.
Calculating the carbon balance can improve the accuracy of the biodegradation performance evaluation (optional, see Appendix E).
This document is applicable to the following materials:
— Natural and/or synthetic polymers, copolymers, or mixtures thereof;
— Plastic materials containing additives such as plasticizers, pigments, or other compounds;
— Water-soluble polymers;
— Materials that do not inhibit the microorganisms in the inoculum under test conditions. The inhibitory effect can be measured using inhibition control or other appropriate methods (see, for example, ISO 8192). If the test materials inhibit the inoculum, other inocula or pre-exposed inocula can be used at lower test concentrations.