Fatty acids, C18 unsatd., mono- and diesters with triethanolamine, di-Me sulfate quaternized

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH
1. HYPOTHESIS FOR THE ANALOGUE APPROACH
The hypothesis for this analogue approach is that target and source substances, being different compounds, have similar physico-chemical properties based on structural similarity with common functional groups; a quaternized ethanolamine moiety, one to three ester groups with a typical UVCB distribution with long-chain fatty acids of natural origin.
Furthermore identical precursors (triethanolamine, long-chain fatty acids, dimethyl sulphate) are used for manufacturing. Therefore common breakdown products via physical and biological processes, which result in structurally similar chemicals, are evident.
For further information refer to general justification for read-across attached to chapter 13 of this IUCLID file.

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
See general justification for read-across attached to chapter 13 of this IUCLID file.

3. ANALOGUE APPROACH JUSTIFICATION
See general justification for read-across attached to chapter 13 of this IUCLID file.

4. DATA MATRIX
See general justification for read-across attached to chapter 13 of this IUCLID file.

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across: supporting information

Water solubility:

2 171 mg/L

Temp.:

10 °C

pH:

3.73

Water solubility:

2 244 mg/L

Temp.:

20 °C

pH:

3.86

Water solubility:

2 359 mg/L

Temp.:

30 °C

pH:

3.83

Results of the preliminary test (ambient temperature/bi-distilled water):A solution with a nominal concentration of 10 mg test item/L was totally dissolved or dispersed with no apparent precipitate or phase separation after 24 h of shaking. A solution with a nominal concentration of 100 mg test item/L showed un-dissolved solid particles after 24 h of shaking.

Results of the main test

1. Time course of the solubility of partially unsaturated TEA-Esterquat at 10, 20, and 30°C in distilled water (pH not adjusted) in equilibrium to atmospheric carbon dioxide

	Temperaturein °C
Time in h	10		20		30
	mg/L	pH	mg/L	pH	mg/L	pH
0 24 48 72	1830 2564 2434 1857	- 3.70 3.74 3.75	1385* 2862 2625 2105	- 3.71 3.90 3.97	1775 2792 2677 2193	- 3.90 3.81 3.78
Mean	2171	3.73	2244	3.86	2359	3.83
Std. Dev.	382	0.03	387	0.13	468	0.06
RSD in %	17.6	0.80	15.3	3.37	19.8	1.57

*regarded as outliner

The water solubility was not found to be temperature dependent.

2. Time course of the solubility of partially unsaturated TEA-Esterquat at 20°C in citric acid buffer (pH 4)

Temperature in °C
Time in h	20
	mg/L	pH
0 24 48 72	5.73 5.01 5.37 5.10	- 4.05 4.05 4.04
Mean	5.30	4.05
Std. Dev.	0.32	0.01
RSD in %	6.0	0.25

3. Time course of the solubility of partially unsaturated TEA-Esterquat at 20°C in phosphate buffer (pH 7)

Temperature in °C
Time in h	20
	mg/L	pH
0 24 48 72	2.93 4.74 2.30 3.57	- 7.09 7.08 7.08
Mean	3.39	7.08
Std. Dev.	1.04	0.01
RSD in %	30.7	0.14

4. Time course of the solubility of partially unsaturated TEA-Esterquat at 20°C in borate buffer (pH 9)

Temperature in °C
Time in h	20
	mg/L	pH
0 24 48 72	5.03* 20.2 19.8 18.3	- 9.06 9.11 9.15
Mean	19.40	9.11
Std. Dev.	1.0	0.05
RSD in %	5.2	0.55

*regarded as outliner

Based on the results in buffered systems it can be assumed that the water solubility is dependent on pH. However, due to the bipolarity of the molecules, it is noted that the counter ions phosphate, citrate and borate, respectively obviously have a more distinct influence on solubility than pH, since the solubility is almost three orders of magnitude below that in pure water. Finally, at higher pH values, a change in composition due to hydrolysis may have a greater influence on the absolute solubility of the test item (see chapter 5.1.2).

Conclusions:

Solubility in buffered water at pH 4-9 and 20°C: 5.30 (pH 4.05), 3.39 (pH 7.08), and 19.4 mg/L (pH 9.11; at 20°C each). Solubility in water without pH adjustment (distilled water being in equilibrium with atmospheric carbon dioxide) at 10, 20, and 30°C: 2171 (pH 3.73, 10°C), 2244 (pH 3.86, 20°C), and 2359 mg/L (pH 3.83, 30°C).

Description of key information

The water solubility of Fatty acids, C18 unsatd., mono and diester with triethanolamine , di-Me sulfate-quaternized used for chemical safety assessment is determined to be 3.39 mg/L (pH 7.01) (OECD TG 105 / EU method A.6); based on read-across information from partially unsaturated TEA-Esterquat.

Key value for chemical safety assessment

Water solubility:

3.39 mg/L

at the temperature of:

20 °C

Additional information

The water solubility of partially unsaturated TEA-Esterquat was investigated in a study conducted according to OECD Guideline 105 and EU-Method A.6 and using HPLC/MS/MS for quantification. HPLC/MS/MS proved to be a suitable analytical tool. Based on the results of the preliminary test, the flask method was used for the determination of the water solubility. In the main test, on the one hand the test item was dissolved in distilled water and the water solubility was measured at 10, 20, and 30°C without adjustment of the pH and on the other hand the water solubility of the test item was determined in buffered systems (pH 4, 7, and 9) at 20°C. The following results were obtained:

1. Solubility in water without pH adjustment (distilled water being in equilibrium with atmospheric carbon dioxide) at 10, 20, and 30°C: 2171 (pH 3.73, 10°C), 2244 (pH 3.86, 20°C), and 2359 mg/L (pH 3.83, 30°C).The water solubility was not found to be temperature dependent.

2. Solubility in buffered water at pH 4-9 and 20°C: 5.30 (pH 4.05), 3.39 (pH 7.08), and 19.4 mg/L (pH 9.11; at 20°C each). Based on the results in buffered systems it can be assumed that the water solubility is dependent on pH.