本文件规定了通过测量封闭式呼吸计中的需氧量或释放的二氧化碳量来确定土壤中塑料材料的最终需氧生物降解性的方法。该方法旨在通过调节试验土壤的湿度来产生最佳的生物降解程度。 如果使用非适应性土壤作为接种物，则试验模拟在自然环境中发生的生物降解过程；如果使用预先暴露的土壤，该方法可用于调查试验材料的潜在生物降解性。 该方法适用于以下材料: -天然和/或合成聚合物、共聚物或其混合物； -含有增塑剂或着色剂等添加剂的塑料材料； -水- 可溶性聚合物。 它不一定适用于在试验条件下抑制土壤中微生物活性的材料。抑制效应可以使用抑制对照或其他合适的方法来测量。如果试验材料抑制土壤中的微生物，可以使用较低的试验材料浓度、另一种土壤或预暴露土壤。

This document specifies a method for determining the ultimate aerobic biodegradability of plastic materials in soil by measuring the oxygen demand in a closed respirometer or the amount of carbon dioxide evolved. The method is designed to yield an optimum degree of biodegradation by adjusting the humidity of the test soil. If a non-adapted soil is used as an inoculum, the test simulates the biodegradation processes which take place in a natural environment; if a pre-exposed soil is used, the method can be used to investigate the potential biodegradability of a test material. This method applies to the following materials: — natural and/or synthetic polymers, copolymers or mixtures of these; — plastic materials which contain additives such as plasticizers or colorants; — water-soluble polymers. It does not necessarily apply to materials which, under the test conditions, inhibit the activity of the microorganisms present in the soil. Inhibitory effects can be measured using an inhibition control or by another suitable method. If the test material inhibits the microorganisms in the soil, a lower test material concentration, another type of soil or a pre-exposed soil can be used.