Registration Dossier

Environmental fate & pathways

Hydrolysis

Currently viewing:

Administrative data

Link to relevant study record(s)

Description of key information

Percent change in the concentration of C6-Pyrazole hemisulfate in buffer solutions at pH 4, 7 and 9 was greater than 10% with no chromatographic peaks been observed for the test substance after 5 days at 50 ± 0.5°C. Therefore, it was found to be hydrolytically unstable under the test conditions at pH 4, 7 and 9.

Key value for chemical safety assessment

Additional information

The hydrolysis of C6-Pyrazole hemisulfate was determined following OECD Guideline 111 (Hydrolysis as a function of pH).

The hydrolysis of the test substance was determined in 3 buffer solutions (pH 4, 7 and 9) at 50 ± 0.5°C. The analytical procedure, SMV (PC) 3200150-01V, for determining the content of C6-Pyrazole hemisulfate in aqueous buffer solutions was also developed in this study.

Test solutions were prepared by dissolving approximately 16 mg test substance in the buffer solutions (pH 4, 7 or 9) and diluting to 500 mL with the same buffer. From the prepared samples, three vials were filled for each pH level (two for hydrolysis testing and one for pH measurement), along with a fourth vial which was filled with blank buffer for each pH level which served as control. All the vials were incubated for 5 days at 50 ± 0.5°C. The samples from each test and buffer solutions were analyzed at the beginning (Day 0) and after 5 days incubation period by using High Performance Liquid Chromatography with UV detection (HPLC-UV). All the test solutions were diluted 0.5 mL to 1 mL with diluent prior to analysis.

The analytical procedure was successfully validated for the quantification of C6-Pyrazole hemisulfate.

Based on the results, percent change in the concentration of C6-Pyrazole hemisulfate in buffer solutions at pH 4, 7 and 9 was greater than 10% with no chromatographic peaks been observed for the test substance after 5 days at 50 ± 0.5°C. Therefore, it was found to be hydrolytically unstable under the test conditions at pH 4, 7 and 9.