Sodium 4-[(C16-18-(even numbered)-alkylamino)carbonyl]benzoate

Solubility in organic solvents / fat solubility

Link to relevant study record(s)

Reference

Endpoint:

solubility in organic solvents / fat solubility

Remarks:

Solubility in octanol

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Qualifier:

equivalent or similar to guideline

Guideline:

other: Method A.6 Water Solubility of Commission Regulation (EC) No 440/2008 of 30 May 2008

Version / remarks:

Flask method based on the regulatory solubility methods

Qualifier:

equivalent or similar to guideline

Guideline:

other: Method 105 of the OECD Guidelines for Testing of Chemicals, 27 July 1995

Version / remarks:

Flask method based on the regulatory solubility methods

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

- Appearance/physical state: White solid
- Batch: A026/99 and A026/50-01
- Purity: 100% (UVCB)
- Expiry date: 01 July 2019
- Storage conditions: Room temperature, in the dark

Medium:

n-octanol

Solubility:

< 0 g/L

Test substance stable:

not determined

Details on results:

On completion of the static re-equilibration period at 20°C, the saturated solution was observed to be a clear colourless solution, containing excess, undissolved test item observed as fine, irregular shaped particular matter, in suspension. This indicated that the solubility of the test item in n-octanol was less than 4.1 x 10-4 g/L of solution at 20°C.

The 72 hour saturation period employed in the evaluation represented the maximum standardized time specified in the two regulatory solubility methods referenced. Due to a number of characteristics presented by this substance, it was necessary to resort to a visual assessment alone to address the solubility of the test item in n-octanol. The test item is known to be insoluble in commonly used chromatographic solvents, including tetrahydrofuran, acetic acid, chloroform, dimethyl sulfoxide, dimethylformamide, water, octane, hexane, pyridine and methanol. This insolubility prevented both the development of a suitable, substance specific method of analysis, as well as the ability to prepare standard solutions of know concentrations with which to accurately quantify the saturated solutions generated by this testing. Gravimetric analysis was considered as an alternative; however the boiling temperature of n-octanol is 195°C and the test item was identified to thermally decompose at approximately this temperature. Therefore, it was concluded that the test item thermal stability/integrity would be compromised during the significant boiling/drying time necessary to evaporate the volumes of n-octanol required to obtain a meaningful solubility limit value gravimetrically.

Conclusions:

The solubility of the test item in n-octanol was determined to be less than 4.1 x 10-4 g/L of solution at 20°C.

Executive summary:

An attempt was made to determine the octanol solubility of sodium 4-[(C16-18-(even numbered)-alkylamino)carbonyl]benzoate, in a GLP-compliant study following OECD guideline 105 (Envigo 2018). The study is considered relevant and reliable for use for this endpoint.

The solubility of the test item in n-octanol was determined to be less than 4.1 x 10-4 g/L of solution at 20°C. Due to the absence of a valid analytical technique to evaluate the saturated solutions generated, a solubility limit test was performed by visual assessment. On completion of the static re-equilibration period at 20°C, the saturated solution was observed to be a clear colourless solution, containing excess, undissolved test item observed as fine, irregular shaped particular matter, in suspension.

Description of key information

The solubility of the test item in n-octanol was determined to be less than 4.1 x 10-4 g/L of solution at 20°C. Due to the absence of a valid analytical technique to evaluate the saturated solutions generated, a solubility limit test was performed by visual assessment. On completion of the static re-equilibration period at 20°C, the saturated solution was observed to be a clear colourless solution, containing excess, undissolved test item observed as fine, irregular shaped particular matter, in suspension.

Additional information

An attempt was made to determine the octanol solubility of sodium 4-[(C16-18-(even numbered)-alkylamino)carbonyl]benzoate, in a GLP-compliant study following OECD guideline 105 (Envigo 2018). The study is considered relevant and reliable for use for this endpoint.