1,4-dihydroxy-2,2,6,6-tetramethyl piperidinium-2-hydroxy-1,2,3-propanetricarboxylate

Endpoint summary

Additional information

CO2 Evolution modified Sturm Test

A study was performed to determine the potential for biodegradation of the test item in water by the carbon dioxide evolution method following OECD Test Guideline 301B adopted 17 July 1992. The amount of carbon dioxide (CO2) released upon biodegradation of the test item and a reference substance, sodium benzoate, was measured. Two blank controls containing inoculum, a metabolically inhibited or abiotic control (containing test substance and a sterilant), and toxicity control (containing inoculum, reference and test substances) were also established to account for background CO2 production, abiotic degradation, and toxicity of the test item, respectively. Based on the CO2 analysis results, the test item cannot be classified as readily biodegradable since the test item degradation during the study was determined to be 19.42 % within 28 days and the degradation of the test item was less than the guideline criteria of 60% degradation within 28 days. The sodium benzoate procedural controls had degraded by 86.4% of the theoretical amount in 28 days. All validation criteria were fulfilled.

 

Zahn-Wellens Test / EMPA-Test

A study was performed to determine the potential for inherent biodegradation of the test item in water by the Zahn-Wellens Test method according to OEDC Test Guideline 302B adopted 17. July 1992. A mixture of a total test volume of 2 litres each containing test item, mineral medium and activated sludge was agitated and aerated at 20 - 25 °C in two glass vessels for 28 days. A reference control running in duplicate containing activated sludge, mineral medium and the reference item, and a blank control containing activated sludge and mineral medium were run under the same test conditions. The biodegradation process was monitored by determination of the dissolved organic carbon concentrations (DOC). The ratio of eliminated DOC, corrected for the blank after each time interval, to the initial DOC value was expressed as the percentage biodegradation at each sampling time. Based on the ratio of eliminated DOC, the test item was classified as inherently biodegradable since the test item degradation during the study was determined to be 77 % after 28. The degradation of the reference item was 100% after 28 days and all validation criteria were fulfilled.