Registration Dossier

Administrative data

Endpoint:
hydrolysis
Data waiving:
study technically not feasible
Justification for data waiving:
the study does not need to be conducted because the substance is highly insoluble in water
Justification for type of information:
JUSTIFICATION FOR DATA WAIVING
Assessment of the hydrolysis as a function of pH in Method C7 abiotic degradation, hydrolysis as a function of pH of commision regulation (EC) No 440/2008 and Method 111 of the OECD guidelines for testing of Chemicals, was not feasible for this test item. This was since the test item is essentially insoluble in water.

Both method guidelines limit the maximum working concentration of the sample solutions to that of half the water solubility of the test item. Based on the estimated water solubility of Solvent Black 46 being less than 1 x 10 -5 g/L, this would limit the maximum permitted concentration to 5 x 10-6 g/l (5 ppb). However due to limitations of the analytical method and the presence of trace levels of starting components remaining as impurities, this still may represent a significant overestimation of the true water solubility.

Performing such studies at these concentrations is not feasible and further to this, the available spectrophotometric method of analysis is not substance specific, in that even if the above concentration solutions in buffer solution could be accurately prepared and losses through absorbance to glassware, etc, excluded; any hydrolysis or dissociation of the test item may not lead to a change in the spectral profile of the sample solutions on analysis.
The test item structure was not supported by the aqueous hydrolysis module of the Epiwin estimation software suite, HYDROWIN, version 2.00, 2000 US EPA.
So, the study was technically not feasible.

Data source

Materials and methods

Results and discussion

Applicant's summary and conclusion