Fatty acids, C8-14 (even numbered) methyl-2-sulfoethyl esters, sodium salts

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Key result

Water solubility:

> 347 g/L

Conc. based on:

test mat. (dissolved fraction)

Temp.:

30 °C

pH:

6.31

Details on results:

Initial testing indicated that the sample was insoluble in water, since residual particulates were observed. However, as the substance is a complex mixture th testing was repeated with a focused on the main constituent components.

Saturated solutions were prepared (in triplicate) by transferring 25.0 g of the test material, followed by water 25.0 g into 100 mL screw topped conical flasks.The three flasks were transferred into a shaker set at 30°C and shaken at 150 rpm. The initial preliminary analysis indicated a significantly lower value due to the presence of a minor component in the test material that was less soluble. The values given for the preliminary analysis were based on a sample following HPLC analysis. It was not possible to prepare a solution at 3-5 times the saturation value as stated in the test procedure, as this would have resulted in a semi-solid / paste. Consequently a 50 % w/w sample was prepared. Following the Day 1 sample shaking and equilibration periods, the sample became a semi-mobile paste. The Day 1 sample was centrifuged for 1 hour, after which no separation of a solid and liquid component was observed. It was not possible to pass the semi mobile paste through a filter prior to analysis by HPLC. Therefore a single sample would be prepared at the highest concentration where a solution / separation was previously achieved. A 33 % w/w sample was prepared, shaken for 3 days at 30°C and allowed to equilibrate for 48 hours prior to analysis. The sample was centrifuged for 45 minutes. This resulted in an opaque supernatant with approximately 5-10 % of a white solid in the base of the centrifuge tube. The sample was
analysed and found to be soluble at 347.1 g/L.

Conclusions:

The sample was found to be soluble at 347.1 g/L.

The solubility reported is based upon the amount of active ingredient that was dissolved in water and not based on the product as a whole. The solubility of the product as a whole would be significantly less due to the relative insolubility of a minor component present in the test material.

Executive summary:

Initial testing indicated that the sample was insoluble in water, since residual particulates were observed. However, as the substance is a complex mixture th testing was repeated with a focused on the main constituent components.

Saturated solutions were prepared (in triplicate) by transferring 25.0 g of the test material, followed by water 25.0 g into 100 mL screw topped conical flasks.The three flasks were transferred into a shaker set at 30°C and shaken at 150 rpm. The initial preliminary analysis indicated a significantly lower value due to the presence of a minor component in the test material that was less soluble. The values given for the preliminary analysis were based on a sample following HPLC analysis. It was not possible to prepare a solution at 3-5 times the saturation value as stated in the test procedure, as this would have resulted in a semi-solid / paste. Consequently a 50 % w/w sample was prepared. Following the Day 1 sample shaking and equilibration periods, the sample became a semi-mobile paste. The Day 1 sample was centrifuged for 1 hour, after which no separation of a solid and liquid component was observed. It was not possible to pass the semi mobile paste through a filter prior to analysis by HPLC. Therefore a single sample would be prepared at the highest concentration where a solution / separation was previously achieved. A 33 % w/w sample was prepared, shaken for 3 days at 30°C and allowed to equilibrate for 48 hours prior to analysis. The sample was centrifuged for 45 minutes. This resulted in an opaque supernatant with approximately 5-10 % of a white solid in the base of the centrifuge tube. The sample was

analysed and found to be soluble at 347.1 g/L.

The solubility reported is based upon the amount of active ingredient that was dissolved in water and not based on the product as a whole. The solubility of the product as a whole would be significantly less due to the relative insolubility of a minor component present in the test material.

Key value for chemical safety assessment

Water solubility:

347 g/L

at the temperature of:

20 °C