2-hydroxy-3-(oleoyloxy)propyl 5-oxo-L-prolinate

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Nov 27 - Dec 05, 2018

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Qualifier:

equivalent or similar to guideline

Guideline:

EU Method A.6 (Water Solubility)

Principles of method if other than guideline:

Flask method with slow stirring

GLP compliance:

yes (incl. QA statement)

Remarks:

Landesamt für Umwelt Rheinland-Pfalz

Type of method:

flask method

Water solubility:

<= 5.41 µg/L

Temp.:

20 °C

pH:

>= 6.05 - <= 6.34

Remarks on result:

other:

Remarks:

the mean at the plateau is stated as range < 0.2 – 5.41 μg/L

Validation Results

Determination of the test item concentrations in the samples was performed following validation report VB17052201G926.

All validation data are summarised in the following table:

Parameter	Value	Unit
Calibrated Range	0.1 – 1	μg/L
Linear term / Slope b	279901.094	counts*min /μg/L
Constant / Intercept a	-717.920	counts*min
Method Variation Coefficient (Precision)	8.98	%
Specificity	was given	-
Accuracy in demineralized water	##	%
Stability in demineralized water after 1 d (nominal 100 mg/L)	49	%
LOD / LOQ in calibration solvent	0.0108 / 0.0325	μg/L
LOD / LOQ in demineralized water#	0.0085 / 0.0255	μg/L

The concentration of the test item in solutions was determined during validation using the following equation:

Concentration [mg/L] = (Peak area - a) / b * sensitivity correction factor

Sensitivity correction factor was calculated from QC (quality control) samples.

Sensitivity correction factor = 100 % / QC recovery in %

Freshly prepared QC samples were injected regularly, and the QC recoveries were taken into account as sensitivity correction factors.

Results

The measurements of flasks 1C (day 8) and 2-6 were used for the calculation of the mean.

Flask	Concentration [μg/L]	Total Mean [μg/L]	Total Standard Deviation [g/L] (Relative standard deviation RSD [%])
1C	0.34	1.07	2.14 (199)
2	0.22
3	< 0.22
4	< 0.22
5	5.41
6	0.45

On the final sampling day a high concentration range (with relative standard deviation 199%) was detected for the finally measured concentration: 1.07 ± 2.14 μg/L.

This high standard deviation may be due to high measurement uncertainty and to the difficulty to prepare mixtures with similar surface of the test item, which is in contact with the surrounding water and therefore important for the dissolution process. Therefore, the mean at the plateau is stated as < 0.2 – 5.41 μg/L (range of six individual vessels).

During this study the dependency of solubility of the nominal load was tested. No dependency on nominal load was detected.

No observations arousing doubts concerning the accuracy of the results and the validity of the study were made.

Description of key information

The mean at the plateau is stated as range < 0.2 – 5.41 μg/L at 20°C and pH = 6.05 – 6.34 (OECD 105, flask method)

Key value for chemical safety assessment

at the temperature of:

20 °C