Amides, C8-18(even-numbered) and C18(unsatd.), N-(2-hydroxypropyl)

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

(Q)SAR

Adequacy of study:

key study

Study period:

From October 2009 to March 2010

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Justification for type of information:

The test substance falls within the applicability domain of the (Q)SAR method.

Principles of method if other than guideline:

The water solubility was estimated using the WATERNT v 1.01 program of EPI SUITE v 4.0.

GLP compliance:

yes (incl. QA statement)

Type of method:

other: estimated

Key result

Water solubility:

>= 3.75 - <= 7.5 mg/L

Conc. based on:

test mat.

Temp.:

25 °C

Remarks on result:

other: Loading, incubation duration and pH not applicable

Details on results:

As it can be seen from Table 1 that, for 7.5 mg of the test substance in 1L of water, the calculated C18 amide amount of 0.17 mg/L exceeds its solubility limit which equals 0.095 mg/L. The same situation appears for the C18’ constituent: The calculated amount of 0.35 mg/L is greater than its water solubility limit of 0.208 mg/L. In case of increasing the amount of Amides, coco, N-(2-hydroxypropyl) to 15 mg/L also the water solubility of C16 amide is exceeded. However for amounts of test substance up to and including 3.75 mg/L, all constituents remain below the predicted solubility limits in water. Overall, based on the comparisons made in Table 1 it can be concluded that, using the WATERNT model, the water solubility of the test substance is estimated to be between 3.75 and 7.5 mg/L.

Table 1. Calculated Amides, coco, N-(2-hydroxypropyl) constituents water solubility and their content in amides, coco, N-(2-hydroxypropyl)-water mixtures

Component	Component concentration (%)	Calculated water solubility at 25 ºC (mg/L)	Constituent concentration after addition of x mg of Amides, coco, N-(2-hydroxypropyl) to 1 L of water (mg/L)
			Amides, coco, N-(2-hydroxypropyl) added (mg/L)
			3.75	7.50	15.0	30.0
Amides:
C8	8.00	13098	0.30	0.60	1.20	2.40
C10	7.00	1258.4	0.26	0.53	1.05	2.10
C12	46.00	119.1	1.73	3.45	6.90	13.80
C14	18.70	11.138	0.70	1.40	2.81	5.61
C16	9.40	1.032	0.35	0.71	1.41	2.82
C18	2.30	0.095	0.09	0.17	0.35	0.69
C18’	4.70	0.208	0.18	0.35	0.71	1.41
C18’’	2.28	0.458	0.09	0.17	0.34	0.68
free amine	0.74	10^6	0.03	0.06	0.11	0.22

Conclusions:

The water solubility of the test substance was found to be between 3.75 and 7.5 mg/L at 25ºC as estimated by WATERNT v 1.01 of EPI SUITE v 4.0.

Executive summary:

The test substance consists of multiple constituents, so that a reliable analytical quantification of its solubility in water is difficult. A visual analysis of solubility was conducted according to EU Method A.6. The water solubility was found to be < 0.100 and < 0.0037 g/L at 20 ºC in preliminary and dilution tests, respectively. Since the experimentally determined values were not considered to be sufficiently reliable, water solubility was also estimated using the WATERNT v 1.01 program of EPI SUITE v 4.0. With this methodology, the water solubility of the test substance was estimated to be between 3.75 and 7.5 mg/L at 25 ºC ( Zieliński, 2010).

Description of key information

The water solubility was determined according to EU Method A.6 (visual observation) as well as modelling using the WATERNT v 1.01 program of EPI SUITE v 4.0.

Further water solubility testing according to OECD Guideline 105 is currently ongoing.

Key value for chemical safety assessment

Water solubility:

3.75 mg/L

at the temperature of:

20 °C