2-octyldodecyl 5-oxo-L-prolinate

Surface tension

Administrative data

Endpoint:

surface tension

Data waiving:

study technically not feasible

Justification for data waiving:

the study does not need to be conducted because water solubility is below 1 mg/L at 20°C

Cross-reference

Reason / purpose for cross-reference:

data waiving: supporting information

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From January 07, 2015 to March 20, 2015

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:

not specified

Type of method:

column elution method

Specific details on test material used for the study:

Batch no.: 192955/01
Appearance: liquid

Key result

Water solubility:

>= 0.009 - <= 0.014 mg/L

Conc. based on:

test mat.

Loading of aqueous phase:

57.2 other: mg test substance

Temp.:

20 °C

pH:

6.3

Remarks on result:

other: first experiment: flow of 25.0 mL/h

Key result

Water solubility:

0.002 mg/L

Conc. based on:

test mat.

Loading of aqueous phase:

51.3 other: mg test substance

Temp.:

20 °C

pH:

6.3

Remarks on result:

other: second experiment: flow of 12.5 mL/h

Details on results:

- At a flow rate of 25 mL/h, the solubilities determined in fractions 7 and 8 were clearly identified as outlier. According to OECD Guideline 105, values from at least five consecutive runs should be taken for evaluation. Therefore, the solubilities determined for fractions 7 and 8 were eliminated. Thus, these values were also eliminated for a flow rate of 12.5 mL/h.
- The remaining values led to a solubility in the range of 9.0 - 14.0 µg/L (mean value 11.5 µg/L) at a flow rate of 25.0 mL/h and to a solubility of 2.0 µg/L at a flow rate of 12.5 mL/h. The overall mean value was 6.8 µg/L. Contrary to the requirements of OECD Guideline 105, the determined concentrations differed more than 30%. This is, however, due to the very low concentration of the test substance. Therefore, a larger difference is also considered acceptable.

The water solubility of the test substance = 2.0 - 14.0 µg/L (formal mean value 6.7 µg/L) at 20°C and pH value of 6.3.

Working range
The calibration curve fits over the working range from 0.6 to 140.8 µg/L (related to 20 mL of water) with r2 = 0.999. A linear fit was used.

Recovery
In the course of the recovery experiment, an average recovery rate of 111% was determined.

Table 1: Quantitative determination of the analytes

Flow rate (mL/h)	Fraction No.	Volume of combined fractions (mL)	IS [µg/L]	Solubility of test substance [µg/L]
25.0	1 (1-2)	20	2.10	12.5
	2 (3-4)	20	2.10	13.5
	3 (5-6)	20	2.10	14.0
	4 (7-8)	20	2.10	9.0
	5 (9-10)	20	2.10	9.5
	6(11-12)	20	2.10	10.5
	7 (13-14)	20	2.10	<0.5
	8 (15-16)	20	2.10	2.0
12.5	1 (1-2)	20	2.10	2.0
	2 (3-4)	20	2.10	2.0
	3 (5-6)	20	2.10	2.0
	4 (7-8)	20	2.10	2.0
	5(9-10)	20	2.10	2.0
	6(11-12)	20	2.10	2.0
	7 (13-14)	20	2.10	2.0
	8 (15-16)	20	2.10	2.0

Conclusions:

Under the study conditions, the water solubility of the test substance was determined to be in the range of 2.0E-03 to 1.4E-02 mg/L at 20°C (mean value 6.7E-3 mg/L).

Executive summary:

A study was conducted to determine the water solubility of the test substance according to OECD Guideline 105. In the preliminary test, the water solubility of the test substance was 10-2 g/L. Therefore, the column elution method was chosen for the main study. A total of 16 aliquots were analyzed by GC-MS at flow rates of 25.0 and 12.5 mL/h. The amounts of test substance used for the first and the second experiment were 57.2 and 51.3 mg, respectively. At a flow rate of 25 mL/h the vwater solubility values were in the range of 9.0E-03 to 1.4E-02 mg/L and at a flow rate of 12.5 mL/h the value was 2.0E-03 mg/L.The overall mean value was 6.7E-03 mg/L. Under the study conditions, the water solubility of the test substance was determined to be in the range of 2.0E-03 - 1.4E-02 mg/L (mean value 6.7E-03 mg/L) at 20°C (Seiler, 2015).