The contact assay measuring the inhibition of Arthrobacter globiformis dehydrogenase activity as an endpoint to evaluate the toxicity of solid samples was tested in an international ring-test to validate its performance for ISO standardization (ISO/CD 18187). This work reports the results of the ring-test involving 9 laboratories from six countries. At least 8 valid data sets were obtained for each sample and more than three quarters of the participants attained the validity criteria defined in the standard. The coefficient of variation within (CV_r) and between (CV_R) laboratories was generally on average <15% and <30% for negative and positive controls, respectively. Regarding solid samples, the laboratories provided a similar ranking of the samples based on their toxicity, despite some variation in the LOEC values. The logarithmic within-lab standard deviation <0.50 for soils and <0.25 for wastes evidenced a good repeatability. The between-lab variability assessed by a CV_R <30%, minimum-maximum factor <4 and a reproducibility standard deviation (SD_R) <0.13 for a great part of the solid samples, confirmed the test reproducibility. Overall, this assay proved to be robust, sensitive and feasible for routine use towards the quality assessment of soils and wastes.

在国际环形试验中测试了接触球蛋白测定法，该接触测定法测量了对球形节杆菌脱氢酶活性的抑制作用，以评估固体样品的毒性，以验证其在ISO标准化方面的性能（ISO / CD 18187）。这项工作报告了来自六个国家/地区的9个实验室进行的环形测试的结果。每个样本至少获得了8个有效数据集，超过四分之三的参与者达到了标准中定义的有效性标准。（CV _r）内和之间（CV _R）阴性对照和阳性对照的实验室平均平均分别<15％和<30％。关于固体样品，尽管LOEC值有所变化，但实验室根据其毒性对样品进行了相似的排名。实验室内对数标准偏差对土壤<0.50，对废物<0.25证明了良好的可重复性。对于大部分固体样品，通过CV _R <30％，最小最大因子<4和可重复性标准偏差（SD _R）<0.13评估的实验室间变异性证实了测试的可重复性。总体而言，该测定方法被证明对于常规用于土壤和废物质量评估是可靠，灵敏且可行的。