Isohexadecyl 12-[(1-oxooctadecyl)oxy]octadecanoate

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

7 Jan - 28 Apr 2015

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

GLP compliance:

no

Type of method:

column elution method

Key result

Water solubility:

1.39 µg/L

Temp.:

20 °C

pH:

6.3

Quantitative determination of the analyte:

Flow rate 25 mL/h	Fraction no.	Volume of combined fractions [mL]	Test substance [µg/L]
-	1(1-2)	26	4.23
-	2(3-4)	26	3.08
-	3(5-6)	25.5	3.14
+	4(7-8)	25	2.00
+	5(9-10)	26	1.54
+	6(11-12)	25.5	1.18
+	7(13-14)	25.5	1.18
+	8(15-16)	26	1.15
Flow rate 50 mL/h
-	1(1-2)	27	3.33
+	2(3-4)	28	2.14
+	3(5-6)	28	1.43
+	4(7-8)	27.5	1.45
+	5(9-10)	27.5	0.73
+	6(11-12)	27.5	1.09
-	7(13-14)	27.5	0.36
-	8(15-16)	27.5	0.36

Internal standard: 2.13 µg/L each fraction

Determination of the water solubility at a flow rate of 25 mL/h yielded values in a range from 1.15 µg/L to 4.23 µg/L and at a flow rate of 12.5 mL/h from 0.36 µg/L to 3.33 µg/L. In contradiction to the guideline, the concentrations differ by more than ±30%. This is however due to the low solubility of the test item. Therefore a larger difference is also considered acceptable.

Calculation of the water solubility was performed by the means of five succesive fractions after achieving a plateau (denoted by "+" in the table above; the discarded fractions are denoted by "-"). Mean values: 1.41 µg/L for the flow rate of 25.0 mL/h and 1.37 µg/L for the flow rate of 12.5 mL/h. The reported value of 1.39 µg/L is a formal mean value of the two; the water solubility ranges between 0.73 and 2.14 µg/L.

The calibration curve fits over a range from 0.426 µg/L to 21.320 µg/L. A quadratic fit was used; r² = 0.999.

Description of key information

1.39 µg/L at 20 °C, pH 6.3 (OECD 105)

Key value for chemical safety assessment

Water solubility:

1.39 µg/L

at the temperature of:

20 °C

Additional information

The water solubility of the substance was determined using column elution method. The determined solubility range was 0.73 -2.14 µg/L. The solubility is very low.