Diphenyl[4-(phenylsulfanyl)phenyl] sulfonium hexafluoroantimonate(1-)

Water solubility

Link to relevant study record(s)

Reference

Endpoint:

water solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

03 December 2018 to 10 June 2019

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 105 (Water Solubility)

Deviations:

yes

Remarks:

The procedure for preliminary test is different to that of method. This is not considered to affect the reliability of the study.

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Deviations:

no

Remarks:

The procedure for preliminary test is different to that of method. This is not considered to affect the reliability of the study.

GLP compliance:

yes (incl. QA statement)

Remarks:

Date of Inspection: 21 August 2018 Date of Issue: 19 November 2018

Type of method:

flask method

Key result

Water solubility:

< 0 g/L

Conc. based on:

test mat.

Temp.:

20 °C

Remarks on result:

other: anionic component

Key result

Water solubility:

0.085 g/L

Conc. based on:

test mat.

Temp.:

20 °C

Remarks on result:

other: cationic component

Preliminary Test

The preliminary estimate of the water solubility was less than 1.03 x 10^-4g/L and greater than 2.0 x 10^-2g/L for the anionic and cationic components respectively. The solution had a pH of 4.3.

Definitive Test

The mean peak areas relating to the standard and sample solutions are shown in the following tables:

Table 2       Samples 1 to 3 (Anionic Component)

Solution	Mean Peak Area
Standard 0.102 mg/L	4.09626 x10^6
Standard 0.256 mg/L	8.13784 x10^6
Standard 0.512 mg/L	1.29506 x10^7
Standard 0.767 mg/L	1.54602 x10^7
Standard 1.01 mg/L	1.71119 x10^7
Standard 1.02 mg/L	1.71883 x10^7
Standard 2.56 mg/L	2.79350 x10^7
Standard 5.12 mg/L	4.12410 x10^7
Matrix blank	none definitively detected
Sample 1A	none definitively detected
Sample 1B	none definitively detected
Sample 2A	none definitively detected
Sample 2B	none definitively detected
Sample 3A	none definitively detected
Sample 3B	none definitively detected

The calibration curve from which the sample concentrations were interpolated had a correlation of 0.992 and the following formula:

y = -1.00 x 10⁶x²+ 1.21 x 10⁷x + 5.37 x10⁶

Table 3       Samples 1 to 3 (Cationic Component)

Solution	Mean Peak Area
Standard 0.102 mg/L	6.93175 x10^6
Standard 0.256 mg/L	1.46662 x10^7
Standard 0.505 mg/L	1.94866 x10^7
Standard 0.512 mg/L	2.51987 x10^7
Standard 0.767 mg/L	2.94927 x10^7
Standard 1.02 mg/L	3.43298 x10^7
Matrix blank	none definitively detected
Sample 1A	2.18866 x10^7
Sample 1B	2.16278 x10^7
Sample 2A	2.64977 x10^7
Sample 2B	2.65706 x10^7
Sample 3A	3.05683 x10^7
Sample 3B	2.94904 x10^7

The calibration curve from which the sample concentrations were interpolated had a correlation of 0.984 and the following formula:

y = -1.61 x 10⁷x²+ 4.73 x 10⁷x + 2.71 x10⁶

Table 4       Samples 4 to 6 (Cationic Component)

Solution	Mean Peak Area
Standard 0.100 mg/L	5.76222 x10^6
Standard 0.251 mg/L	1.23901 x10^7
Standard 0.502 mg/L	2.20203 x10^7
Standard 0.509 mg/L	2.31778 x10^7
Standard 0.752 mg/L	2.98770 x10^7
Standard 1.00 mg/L	3.34279 x10^7
Matrix blank	none definitively detected
Sample 4A	2.21111 x10^7
Sample 4B	2.22164 x10^7
Sample 5A	2.69456 x10^7
Sample 5B	2.63677 x10^7
Sample 6A	2.51801 x10^7
Sample 6B	2.37522 x10^7

The calibration curve from which the sample concentrations were interpolated had a correlation of 0.999 and the following formula:

y = -2.26 x 10⁷x²+ 5.60 x 10⁷x + 1.14 x10⁵

The concentration (g/L) of test item in the sample solutions is shown in the following tables:

Table 5       Anionic Component

Sample Number	Time Shaken at ~ 30 ºC (hours)	Concentration (g/L)	Solution pH
1	24	<1.02 x 10^-4	3.9
2	48	<1.02 x 10^-4	3.9
3	72	<1.02 x 10^-4	3.8

Mean anionic component concentration: less than 1.02 x 10^-4g/L at 20.0 ± 0.5 ºC

Table 6       Cationic Component

Sample Number	Time Shaken at ~ 30 ºC (hours)	Concentration (g/L)	Solution pH
1	24	3.85 x 10^-2	3.9
2	48	5.16 x 10^-2	3.9
3	72	6.32 x 10^-2	3.8
4	96	7.36 x 10^-2	3.4
5	120	9.56 x 10^-2	3.4
6	144	8.43 x 10^-2	3.4

Mean cationic component concentration (Samples 4 to 6): 8.45 x 10^-2g/L at 20.0 ± 0.5 ºC

Discussion

On completion of the equlibration period, the samples were clear and colourless liquids with excess test item present. After filtration, the filtrates were visually observed to be clear, colourless liquids free from un-dissolved test item and had no definitive Tyndall beam effect.

The test item was a salt comprised of an inorganic anion and an organic cation. The water solubility was determined for both of these components using positive mode on the mass spectrometer for the cation and negative mode for the anion.

As the water solubility was determined during the preliminary test to be above 10^-2g/L for the cationic component, the flask shaking test was performed even though the anionic component had a preliminary solubility of below 10^-2g/L. However, as the anionic component was inorganic, the column elution method would not have been appropriate.

The preliminary result for the cationic component was reported as a limit value as it was beyond the calibration range.

The results for the anionic component were reported on limit values based on the lowest standard used for calibration as no definitive peak for the component was detected in the samples.

As the results for Samples 1 to 3 appeared to be increasing as shaking time increased, it was decided to utilise the test guideline option of increased shaking time. An increased loading rate was used for Samples 4 to 6 to cover the expected higher concentration and because the result for Sample 3 was approaching the loading rate used.

The results for Samples 4 to 6 were within ± 15 % of the mean, thus satisfying the criteria specified in the guidelines.

Conclusions:

The water solubility of the test item has been determined at 20.0 ± 0.5 °C to be less than 1.02 E-04 g/L of solution and 8.45E-02 g/L of solution for the anionic and cationic components of the test item respectively.

Executive summary:

The water solubility was determined to be less than 1.02 x 10^-4g/L and 8.45 x 10^-2g/L for the anionic and cationic components of the test item respectively at 20.0 ± 0.5 °C, using the flask method, designed to be compatible with Method A.6 Water Solubility of Commission Regulation (EC) No 440/2008 of 30 May 2008 and Method 105 of the OECD Guidelines for Testing of Chemicals, 27 July 1995.

Description of key information

Cationic component: 8.45 x 10^-2g/L at 20.0 ± 0.5 ºC ; Anionic component: less than 1.02 x 10^-4g/L at 20.0 ± 0.5 ºC; OECD 105; Fox J M (2019)