Hexafluoropropene, oxidized, oligomers, reduced, fluorinated

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

10 January 2013 to 28 January 2013

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

OECD Guideline-conform study conducted under GLP.

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Water solubility:

466.6 mg/L

Temp.:

20 °C

pH:

8.6

Remarks on result:

other: The quality criteria of the A.6 method were verified (RSD% over three values is < 15%).

Galden Low Molecular Weight: details on water solubility test

Flask code	As	Cs (ng/mL)	Ds*	Water Solubility (ng/mL)	Water Solubility (mg/L)
A	387819	2.42	200.0	484.62	0.485
B	358311	2.24	200.0	448.01	0.448
C	356243	2.23	200.0	445.44	0.445
D	364186	2.28	200.0	455.30	0.455
E	386592	2.42	200.0	483.09	0.483
F	386589	2.42	200.0	483.09	0.483
Mean value :				466.6	0.47
Standard deviation (S.D.) :				18.9	0.02
Relative Standard Deviation (RSD%) :				4.06%	4.06%

*The dilution step can be considered reliable since it was performed six times on six different sample aliquots, obtaining an acceptable relative standard deviation.

As       =         Peak area of the test item in the aqueous fractions

Ds       =         Dilution

Cs value is calculated from the As data using linear calibration curve obtained with Cstd and Astd data from injections of the working standard solutions for each reference material.

Conclusions:

Interpretation of results (migrated information): slightly soluble (0.1-100 mg/L)
The water solubility of GALDEN LMW is 0.47 mg/L at 20°C.

Executive summary:

The study was conducted under GLP according to the OECD Test Guideline No. 105, flask method.

Six samples (about 2 g each) of test item were weighed into six 100 mL conical glass flasks, 100 mL of water analytical grade were added and each flask was closed with a polypropylene stopper. Two flasks, labelled “A” and “B”, were shaken at 30°C in a thermostatic mechanical shaker for 24 hours, two flasks, labelled “C” and “D”, were shaken at 30°C in a thermostatic mechanical shaker for 48 hours, two flasks, labelled “E” and “F”, were shaken at 30°C in a thermostatic mechanical shaker for 72 hours. Then all the flasks were allowed to stand at 20°C in a thermostatic oven for 24 hours.

The pH value of the sample solutions was determined by the pH meter equipped with a glass electrode.

 

The determination of the test item was performed by GC using an external standard and MS single Quadrupole triple axis detector.

Three working standard solutions of GALDEN LMW (WSS1 =0.05ng/mL, WSS2 =0.5ng/mL, WSS3 =5ng/mL) were used for linear calibration.

 

Preliminary non GLP tests on the test item were carried out to avoid any chromatographic peak of impurities or degradation products interfering with the test item peak and to determine the optimum chromatographic conditions.

 

From the obtained experimental data it can be concluded that the water solubility of GALDEN LMWis 0.47 mg/L at 20°C.

Description of key information

Water solubility of GALDEN LMW was experimetally determined  to be 0.47 mg/L.

Key value for chemical safety assessment

Water solubility:

0.47 mg/L

at the temperature of:

20 °C

Additional information

The water solubility of GALDEN LMW was determined under a GLP study conducted according to the OECD Test Guideline No. 105, flask method, which was considered appropriate to test the substance.

According to the results, it can be concluded that the water solubility of GALDEN LMW is 0.47 mg/L at 20°C.

Galden is a multi-constituent substance consisting of low molecular weight perfluoropolyethers (PFPE). Perfluorinated substances typically have a low affinity for water. Two grades of Galden LMW are manufactured (Galden HT55 and Galden HT70), which contain the same perfluorinated constituents, but differ only in the relative concentration of the constituents.

As the two grades both contain only perfluorinated constituents (albeit in different relative concentrations), the water solubility of both Galden grades is very similar. The value of 0.47 mg/L therefore is representative for both grades.

 

A previous study, not conducted according to official guidelines was disregarded, since the method and the result cannot be considered reliable. According to that method, the water solubility of GALDEN LMW was determined to be 5 mg/L at 22 °C, value that markedly differs from the one obtained by the more recent study conducted under GLP and according to OECD Test Guideline No. 105.

Moreover due the lack of detailed information on the analytical method and its validation, the reliability of the analytical quantification cannot be defined.