Hydrocarbons, C11-C16, n-alkanes, isoalkanes,

Water solubility

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

water solubility

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Study period:

Experimental Starting Date: 10 July 2014 Experimental Completion Date: 04 September 2014

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Study conducted in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not affect the quality of the relevant results. The study report was conclusive, done to a valid guideline and the study was conducted under GLP conditions.

Justification for type of information:

The hypothesis for the analogue approach is that the test substance, Hydrocarbons, C12-C15, n-alkanes, isoalkanes <2% aromatics contains constituents which are also constituents of the target substance, Hydrocarbons, C11-C16, n-alkanes, isoalkanes, <2% aromatics. The substances have overlapping constituents and therefore have qualitatively similar properties (RAAF Scenario 2 applies).

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Version / remarks:

slow stir adaptation of the standard method

Principles of method if other than guideline:

The water solubility of Shell GTL Solvent GS215 at 20.0 ± 0.5 °C was evaluated using a slow stir adaptation of the standard test method, based on the findings of Letinski, D.J., Connolly, M.J., Peterson, D.R. and Parkerton, T.F. (2002) “Slow-stir water solubility measurements of selected alcohols and diesters”, Chemosphere 48, 257-265. The method employed was designed to be compatible with the data endpoint requirements of Method A6 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.

GLP compliance:

yes

Type of method:

other: slow stir adaptation of the standard method

Key result

Water solubility:

< 0 g/L

Temp.:

20 °C

Remarks on result:

other: Initial Nominal Loading Rate of 100 mg/L

Key result

Water solubility:

< 0 g/L

Temp.:

20 °C

Remarks on result:

other: Initial Nominal Loading Rate of 10 mg/L

Results

Main Test

The mean peak area ratios relating to the standard, sample and blank solutions are shown in the following tables:

 

Table 3.1– Nominal 100 mg/L Loading Rate

Solution	Mean Peak Area Ratio
Standard 10.8 mg/L	1.1473
Standard 10.1 mg/L	1.0771
Vessel 1 Sample 1	0.12275
Vessel 2 Sample 1	0.085385
Vessel 3 Sample 1	0.046270
Sample Blank	0.0032304
Standard 11.0 mg/L	1.1922
Standard 11.8 mg/L	1.3038
Vessel 1 Sample 2	0.067474
Vessel 1 Sample 3	0.046431
Vessel 2 Sample 2	0.061652
Vessel 2 Sample 3	0.027280
Vessel 3 Sample 2	0.030694
Vessel 3 Sample 3	0.048124
Sample Blank	0.0025111
Standard 11.3 mg/L	1.2304
Standard 12.1 mg/L[1]	1.1256
Vessel 1 Sample 4	0.00079501
Vessel 2 Sample 4	0.0065702
Vessel 3 Sample 4	0.0031705
Sample Blank	0.0095884

 

Table 3.1– Nominal 100 mg/L Loading Rate - Continued

Solution	Mean Peak Area Ratio
Standard 11.2 mg/L	1.1371
Standard 11.4 mg/L	1.2200
Vessel 1 Sample 5	0.047893
Vessel 1 Sample 6	0.00069220
Vessel 2 Sample 5	0.051351
Vessel 2 Sample 6	0.00081300
Vessel 3 Sample 5	0.059822
Vessel 3 Sample 6	0.0011707
Sample Blank	0.0019236

 

[1]Standard not used due to inconsistent response compared with other analyses.

Table 3.2– Nominal 10 mg/L Loading Rate

Solution	Mean Peak Area Ratio
Standard 10.8 mg/L	1.1473
Standard 10.1 mg/L	1.0771
Vessel 1 Sample 1	0.0091066
Vessel 2 Sample 1	0.0050910
Vessel 3 Sample 1	0.0079817
Sample Blank	0.0032304
Standard 11.0 mg/L	1.2074
Standard 11.8 mg/L	1.3067
Vessel 1 Sample 2	0.0075881
Vessel 1 Sample 3	0.0055487
Vessel 2 Sample 2	0.0074122
Vessel 2 Sample 3	0.0041110
Vessel 3 Sample 2	0.0088293
Vessel 3 Sample 3	0.0020043
Sample Blank	0.0025111

 

 

 

Table 3.2– Nominal 10 mg/L Loading Rate - Continued

Solution	Mean Peak Area Ratio
Standard 11.3 mg/L	1.2304
Standard 12.1 mg/L[2]	1.1256
Vessel 1 Sample 4	0.056688
Vessel 2 Sample 4	0.059110
Vessel 3 Sample 4	0.043786
Sample Blank	0.0095884
Standard 11.2 mg/L	1.2237
Standard 11.4 mg/L	1.2197
Vessel 1 Sample 5	0.0032338
Vessel 1 Sample 6	0.040415
Vessel 2 Sample 5	0.0064997
Vessel 2 Sample 6	0.029020
Vessel 3 Sample 5	0.0098106
Vessel 3 Sample 6	0.035627
Sample Blank	0.0019236

 

[1]Standard not used due to inconsistent response compared with other analyses.

As the test item peaks covered a wide retention time range and there were peaks observed in the blank solutions over the same range, the concentration attributed to the blank was subtracted from the sample concentrations. 

 

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

 

Table 3.3– Nominal 100 mg/L Loading Rate, Vessel 1

Sample Number	Stirring / Equilibration Time (hours)	Concentration (g/L)	Solution pH
1	42.3	1.11 x 10^-5	6.66
2	114.0	5.87 x 10^-6	6.68
3	119.8	3.97 x 10^-6	6.90
4	137.0	-7.98 x 10^-7	6.49
5	160.5	4.36 x 10^-6	6.69
6	166.7	-1.17 x 10^-7	6.82

 

A variable, negligible quantity was detected in the retention time range of the test item in both samples and sample blank. The amount detected was well below the range investigated for the analysis. The result is therefore taken as less than the level at which successful detection of the test item was achieved. See validation and discussion in overall remarks and attachments section below.

Table 3.4– Nominal 100 mg/L Loading Rate, Vessel 2

Sample Number	Stirring / Equilibration Time (hours)	Concentration (g/L)	Solution pH
1	42.3	7.65 x 10^-6	6.81
2	114.0	5.35 x 10^-6	6.70
3	119.8	2.24 x 10^-6	6.89
4	137.0	-2.74 x 10^-7	6.54
5	160.5	4.69 x 10^-6	6.91
6	166.7	-1.05 x 10^-7	6.45

 

A variable, negligible quantity was detected in the retention time range of the test item in both samples and sample blank. The amount detected was well below the range investigated for the analysis. The result is therefore taken as less than the level at which successful detection of the test item was achieved. See validation and discussion in overall remarks and attachments section below.

 

 

Table 3.5– Nominal 100 mg/L Loading Rate, Vessel 3

Sample Number	Stirring / Equilibration Time (hours)	Concentration (g/L)	Solution pH
1	42.3	4.01 x 10^-6	6.71
2	114.0	2.55 x 10^-6	6.61
3	119.8	4.12 x 10^-6	6.70
4	137.0	-5.83 x 10^-7	6.42
5	160.5	5.49 x 10^-6	6.72
6	166.7	-7.14 x 10^-8	6.51

 

A variable, negligible quantity was detected in the retention time range of the test item in both samples and sample blank. The amount detected was well below the range investigated for the analysis. The result is therefore taken as less than the level at which successful detection of the test item was achieved. See validation and discussion in overall remarks and attachments section below.

 

Table 3.6– Nominal 10 mg/L Loading Rate, Vessel 1

Sample Number	Stirring / Equilibration Time (hours)	Concentration (g/L)	Solution pH
1	42.3	5.47 x 10^-7	6.92
2	114.0	4.54 x 10^-7	6.84
3	119.8	2.71 x 10^-7	6.81
4	137.0	4.28 x 10^-6	6.41
5	160.5	1.13 x 10^-7	6.72
6	166.7	3.51 x 10^-6	6.41

 

A variable, negligible quantity was detected in the retention time range of the test item in both samples and sample blank. The amount detected was well below the range investigated for the analysis. The result is therefore taken as less than the level at which successful detection of the test item was achieved. See validation and discussion in overall remarks and attachments section below.

 

 

Table 3.7– Nominal 10 mg/L Loading Rate, Vessel 2

Sample Number	Stirring / Equilibration Time (hours)	Concentration (g/L)	Solution pH
1	42.3	1.73 x 10^-7	6.91
2	114.0	4.38 x 10^-7	6.72
3	119.8	1.42 x 10^-7	6.69
4	137.0	4.50 x 10^-6	6.42
5	160.5	4.12 x 10^-7	6.73
6	166.7	2.47 x 10^-6	6.44

 

A variable, negligible quantity was detected in the retention time range of the test item in both samples and sample blank. The amount detected was well below the range investigated for the analysis. The result is therefore taken as less than the level at which successful detection of the test item was achieved. See validation and discussion in overall remarks and attachments section below.

 

Table 3.8– Nominal 10 mg/L Loading Rate, Vessel 3

Sample Number	Stirring / Equilibration Time (hours)	Concentration (g/L)	Solution pH
1	42.3	4.43 x 10^-7	6.84
2	114.0	5.65 x 10^-7	6.94
3	119.8	-4.71 x 10^-8	6.82
4	137.0	3.10 x 10^-6	6.50
5	160.5	7.15 x 10^-7	6.77
6	166.7	3.08 x 10^-6	6.60

 

A variable, negligible quantity was detected in the retention time range of the test item in both samples and sample blank. The amount detected was well below the range investigated for the analysis. The result is therefore taken as less than the level at which successful detection of the test item was achieved. See validation and discussion in overall remarks and attachments section below.

 

The overall water solubility results for the two different loading rates evaluated are summarized in the following tables:

 

Table 3.9– Nominal 100 mg/L Loading Rate

Vessel	1	2	3
Mean Water Solubility (g/L at 20.0 ± 0.5 ºC)	< 1.20 x 10^-4	< 1.20 x 10^-4	< 1.20 x 10^-4
Standard Deviation	not applicable	not applicable	not applicable
Relative Standard Deviation	not applicable	not applicable	not applicable

 

Overall water solubility                             :         less than 1.20x 10^-4g/L at 20.0 ± 0.5 ºC

 

Table 3.10– Nominal 10 mg/L Loading Rate

Vessel	1	2	3
Mean Water Solubility (g/L at 20.0 ± 0.5 ºC)	< 1.20 x 10^-4	< 1.20 x 10^-4	< 1.20 x 10^-4
Standard Deviation	not applicable	not applicable	not applicable
Relative Standard Deviation	not applicable	not applicable	not applicable

 

Overall water solubility                             :         less than 1.20x 10^-4g/L at 20.0 ± 0.5 ºC

Conclusions:

Interpretation of results: insoluble (< 0.1 mg/L)

Please see Conclusion within the Executive Summary Section below.

Executive summary:

The determination was carried out using a slow stiradaptation of the standard test method, based on thefindings of Letinski, D.J., Connolly, M.J., Peterson, D.R. and Parkerton, T.F. (2002) “Slow-stir water solubility measurements of selected alcohols and diesters”, Chemosphere 48, 257-265. The method employed was designedto be compatible with the data endpoint requirements of Method A6 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.

 

The slow-stir procedure was used as during a previous study (Harlan Study Number 41304205) using the flask method, it was identified that excess, undissolved test item could not be successfully excluded from the saturated solutions. The slow stir method eliminated dispersion of the test item throughout the solution and thus allowed isolation of saturated solutions free from excess, undissolved test item suitable for analysis.

 

Slow-stirring therefore enables the solubilisation of the test item without the formation of potentially problematic micro-droplets. The alternative column elution method proposed by the guidelines for addressing substances of low solubility is poorly suited to liquid test items.

 

As the test item is a UVCB substance, the effect of initial loading rate was also evaluated during the definitive determination of water solubility, using initial nominal loading rates of 100 mg/L and 10 mg/L, in order to assess if this affected either the resulting aqueous concentration or the composition of the dissolved fraction.

   

Conclusion

The water solubility of the test item at 20.0 ± 0.5 °C was evaluated using a slow stiradaptation of the standard test method. The results are summarized in the following table:

 

Table 3.11

Initial Nominal Loading Rate	Water Solubility  (g/L of solution at 20.0 ± 0.5 °C)
100 mg/L	< 1.20x 10^-4
10 mg/L	< 1.20x 10^-4

 

Reference 2

Endpoint:

water solubility

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Study period:

Experimental Starting Date: 10 July 2014 Experimental Completion Date: 17 October 2014

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

The hypothesis for the analogue approach is that the test substance, Hydrocarbons, C14-C16, n-alkanes, isoalkanes, <2% aromatics contains constituents which are also constituents of the target substance, Hydrocarbons, C11-C16, n-alkanes, isoalkanes, <2% aromatics. The substances have overlapping constituents and therefore have qualitatively similar properties (RAAF Scenario 2 applies).

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

according to guideline

Guideline:

EU Method A.6 (Water Solubility)

Version / remarks:

slow stir adaptation of the standard method

Deviations:

no

Principles of method if other than guideline:

The water solubility of Shell GTL Solvent GS250 at 20.0 ± 0.5 °C was evaluated using a slow stir adaptation of the standard test method, based on the findings of Letinski, D.J., Connolly, M.J., Peterson, D.R. and Parkerton, T.F. (2002) “Slow-stir water solubility measurements of selected alcohols and diesters”, Chemosphere 48, 257-265. The method employed was designed to be compatible with the data endpoint requirements of Method A6 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.

GLP compliance:

yes

Type of method:

other: slow-stir adaptation of standard method

Key result

Water solubility:

< 0 g/L

Temp.:

20 °C

Remarks on result:

other: Initial Nominal Loading Rate of 100 mg/L

Key result

Water solubility:

< 0 g/L

Temp.:

20 °C

Remarks on result:

other: Initial Nominal Loading Rate of 10 mg/L

Results

Main Test

The mean peak area ratios relating to the standard, sample and blank solutions are shown in the following tables:

 

Table 3.1– Nominal 100 mg/L Loading Rate

Solution	Mean Peak Area Ratio
Standard 13.1 mg/L	1.2455
Standard 11.9 mg/L	1.1236
Vessel 1 Sample 1	0.025338
Vessel 2 Sample 1	0.018761
Vessel 3 Sample 1	0.014080
Sample Blank	0.014589
Standard 11.8 mg/L	1.1496
Standard 11.0 mg/L	0.97343
Vessel 1 Sample 2	0.034150
Vessel 1 Sample 3	0.015391
Vessel 2 Sample 2	0.011149
Vessel 2 Sample 3	0.14443
Vessel 3 Sample 2	0.018739
Vessel 3 Sample 3	0.013605
Sample Blank	0.0098544
Standard 11.6 mg/L	1.0472
Standard 11.6 mg/L	1.0394
Vessel 1 Sample 4	0.012603
Vessel 1 Sample 5	0.014919
Vessel 2 Sample 4	0.013304
Vessel 2 Sample 5	0.089442
Vessel 3 Sample 4	0.012701
Vessel 3 Sample 5	0.018584
Sample Blank	0.011041

 

Table 3.1– Nominal 100 mg/L Loading Rate - Continued

Solution	Mean Peak Area Ratio
Standard 12.0 mg/L	1.0897
Standard 14.2 mg/L	1.3738
Vessel 1 Sample 6	0.012388
Vessel 2 Sample 6	0.013000
Vessel 3 Sample 6	0.012906
Sample Blank	0.0088541

 

Table 3.2– Nominal 10 mg/L Loading Rate

Solution	Mean Peak Area Ratio
Standard 13.1 mg/L	1.2455
Standard 11.9 mg/L	1.1236
Vessel 1 Sample 1	0.036757
Vessel 2 Sample 1	0.015738
Vessel 3 Sample 1	0.014172
Sample Blank	0.014589
Standard 11.8 mg/L	1.1401
Standard 11.0 mg/L	0.96982
Vessel 1 Sample 2	0.024546
Vessel 1 Sample 3	0.015647
Vessel 2 Sample 2	0.028618
Vessel 2 Sample 3	0.0170820
Vessel 3 Sample 2	0.0099977
Vessel 3 Sample 3	0.033146
Sample Blank	0.0098544

 

 

 

Table 3.2– Nominal 10 mg/L Loading Rate - Continued

Solution	Mean Peak Area Ratio
Standard 11.6 mg/L	1.0383
Standard 11.6 mg/L	1.0401
Vessel 1 Sample 4	0.011069
Vessel 1 Sample 5	0.011206
Vessel 2 Sample 4	0.022098
Vessel 2 Sample 5	0.014229
Vessel 3 Sample 4	0.013482
Vessel 3 Sample 5	0.012506
Sample Blank	0.011041
Standard 12.0 mg/L	1.0897
Standard 14.2 mg/L	1.3738
Vessel 1 Sample 6	0.0056822
Vessel 2 Sample 6	0.0080248
Vessel 3 Sample 6	0.010143
Sample Blank	0.0088541

 

As the test item peaks covered a wide retention time range and there were peaks observed in the blank solutions over the same range, the concentration attributed to the blank was subtracted from the sample concentrations. 

 

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

 

Table3.3– Nominal 100 mg/L Loading Rate, Vessel 1

Sample Number	Stirring / Equilibration Time (hours)	Concentration (g/L)	Solution pH
1	23.3	1.13 x 10^-6	6.95
2	47.2	2.60 x 10^-6	6.78
3	54.5	5.94 x 10^-7	7.00
4	71.1	1.74 x 10^-7	6.78
5	76.7	4.31 x 10^-7	6.79
6	95.1	3.77 x 10^-7	6.62

 

A variable, negligible quantity was detected in the retention time range of the test item in both samples and sample blank. The amount detected was well below the range investigated for the analysis. The result is therefore taken as less than the level at which successful detection of the test item was achieved. See validation and discussion within overall remarks and attachments section below.

 

Table 3.4– Nominal 100 mg/L Loading Rate, Vessel 2

Sample Number	Stirring / Equilibration Time (hours)	Concentration (g/L)	Solution pH
1	23.3	4.40 x 10^-7	7.00
2	47.2	1.39 x 10^-7	6.66
3	54.5	1.44 x 10^-5	6.91
4	71.1	2.52 x 10^-7	6.91
5	76.7	8.72 x 10^-6	6.88
6	95.1	4.43 x 10^-7	6.63

 

A variable, negligible quantity was detected in the retention time range of the test item in both samples and sample blank. The amount detected was well below the range investigated for the analysis. The result is therefore taken as less than the level at which successful detection of the test item was achieved. See validation and discussion within overall remarks and attachments section below.

 

 

Table3.5– Nominal 100 mg/L Loading Rate, Vessel 3

Sample Number	Stirring / Equilibration Time (hours)	Concentration (g/L)	Solution pH
1	23.3	-5.37 x 10^-8	6.89
2	47.2	9.53 x 10^-7	6.94
3	54.5	4.02 x 10^-7	6.89
4	71.1	1.85 x 10^-7	7.09
5	76.7	8.39 x 10^-7	6.88
6	95.1	4.33 x 10^-7	6.71

 

A variable, negligible quantity was detected in the retention time range of the test item in both samples and sample blank. The amount detected was well below the range investigated for the analysis. The result is therefore taken as less than the level at which successful detection of the test item was achieved. See validation and discussion within overall remarks and attachments section below.

 

Table3.6– Nominal 10 mg/L Loading Rate, Vessel 1

Sample Number	Stirring / Equilibration Time (hours)	Concentration (g/L)	Solution pH
1	23.3	2.34 x 10^-6	6.84
2	47.2	1.59 x 10^-6	7.10
3	54.5	6.31 x 10^-7	6.90
4	71.1	8.00 x 10^-9	7.15
5	76.7	2.32 x 10^-8	6.94
6	95.1	-3.39 x 10^-7	6.77

 

A variable, negligible quantity was detected in the retention time range of the test item in both samples and sample blank. The amount detected was well below the range investigated for the analysis. The result is therefore taken as less than the level at which successful detection of the test item was achieved. See validation and discussion within overall remarks and attachments section below.

 

 

Table 3.7– Nominal 10 mg/L Loading Rate, Vessel 2

Sample Number	Stirring / Equilibration Time (hours)	Concentration (g/L)	Solution pH
1	23.3	1.21 x 10^-7	6.79
2	47.2	2.03 x 10^-6	6.91
3	54.5	9.99 x 10^-8	6.97
4	71.1	1.24 x 10^-6	6.66
5	76.7	3.61 x 10^-7	7.02
6	95.1	-8.86 x 10^-8	6.90

 

A variable, negligible quantity was detected in the retention time range of the test item in both samples and sample blank. The amount detected was well below the range investigated for the analysis. The result is therefore taken as less than the level at which successful detection of the test item was achieved. See validation and discussion within overall remarks and attachments section below.

 

Table 3.8– Nominal 10 mg/L Loading Rate, Vessel 3

Sample Number	Stirring / Equilibration Time (hours)	Concentration (g/L)	Solution pH
1	23.3	-4.40 x 10^-8	6.87
2	47.2	2.20 x 10^-8	6.99
3	54.5	2.52 x 10^-6	6.66
4	71.1	2.77 x 10^-7	6.90
5	76.7	1.68 x 10^-7	6.98
6	95.1	1.38 x 10^-7	6.79

 

A variable, negligible quantity was detected in the retention time range of the test item in both samples and sample blank. The amount detected was well below the range investigated for the analysis. The result is therefore taken as less than the level at which successful detection of the test item was achieved. See validation and discussion within overall remarks and attachments section below.

 

 

The overall water solubility results for the two different loading rates evaluated are summarized in the following tables:

 

Table 3.9– Nominal 100 mg/L Loading Rate

Vessel	1	2	3
Mean Water Solubility (g/L at 20.0 ± 0.5 ºC)	< 1.01 x 10^-4	< 1.01 x 10^-4	< 1.01 x 10^-4
Standard Deviation	not applicable	not applicable	not applicable
Relative Standard Deviation	not applicable	not applicable	not applicable

 

Overall water solubility                             :         less than 1.01x 10^-4g/L at 20.0 ± 0.5 ºC

 

Table 3.10– Nominal 10 mg/L Loading Rate

Vessel	1	2	3
Mean Water Solubility (g/L at 20.0 ± 0.5 ºC)	< 1.01 x 10^-4	< 1.01 x 10^-4	< 1.01 x 10^-4
Standard Deviation	not applicable	not applicable	not applicable
Relative Standard Deviation	not applicable	not applicable	not applicable

 

Overall water solubility                             :         less than 1.01x 10^-4g/L at 20.0 ± 0.5 ºC

Conclusions:

Please see the Conclusion within the Executive Summary Section below.

Executive summary:

The determination was carried out using a slow stiradaptation of the standard test method, based on thefindings of Letinski, D.J., Connolly, M.J., Peterson, D.R. and Parkerton, T.F. (2002) “Slow-stir water solubility measurements of selected alcohols and diesters”, Chemosphere 48, 257-265. The method employed was designedto be compatible with the data endpoint requirements of Method A6 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.

 

The slow-stir procedure was used as during a previous study (Harlan Study Number 41304206) using the flask method, it was identified that excess, undissolved test item could not be successfully excluded from the saturated solutions. The slow stir method eliminated dispersion of the test item throughout the solution and thus allowed isolation of saturated solutions free from excess, undissolved test item suitable for analysis.

 

Slow-stirring therefore enables the solubilisation of the test item without the formation of potentially problematic micro-droplets. The alternative column elution method proposed by the guidelines for addressing substances of low solubility is poorly suited to liquid test items.

 

As the test item is a UVCB substance, the effect of initial loading rate was also evaluated during the definitive determination of water solubility, using initial nominal loading rates of 100 mg/L and 10 mg/L, in order to assess if this affected either the resulting aqueous concentration or the composition of the dissolved fraction.

 

Conclusion

The water solubility of the test item at 20.0 ± 0.5 °C was evaluated using a slow stiradaptation of the standard test method. The results are summarized in the following table:

 

Table 3.11

Initial Nominal Loading Rate	Water Solubility  (g/L of solution at 20.0 ± 0.5 °C)
100 mg/L	< 1.01x 10^-4
10 mg/L	< 1.01x 10^-4

Reference 3

Endpoint:

water solubility

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

weight of evidence

Study period:

Experimental Starting Date: 10 July 2014 Experimental Completion Date: 25 October 2014

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Justification for type of information:

The hypothesis for the analogue approach is that the test substance, Hydrocarbons, C15-C19, n-alkanes, isoalkanes, <2% aromatics contains constituents which are also constituents of the target substance, Hydrocarbons, C11-C16, n-alkanes, isoalkanes, <2% aromatics. The substances have overlapping constituents and therefore have qualitatively similar properties (RAAF Scenario 2 applies).

Reason / purpose for cross-reference:

read-across: supporting information

Qualifier:

according to guideline

Guideline:

other:

Deviations:

no

Principles of method if other than guideline:

The determination was carried out using a slow stir adaptation of the standard test method, based on the findings of Letinski, D.J., Connolly, M.J., Peterson, D.R. and Parkerton, T.F. (2002) “Slow-stir water solubility measurements of selected alcohols and diesters”, Chemosphere 48, 257-265. The method employed was designed to be compatible with the data endpoint requirements of Method A6 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.

GLP compliance:

yes

Type of method:

other: slow-stir adaptation of standard method

Key result

Water solubility:

< 0 g/L

Temp.:

20 °C

Remarks on result:

other: Initial Nominal Loading Rate of 100 mg/L

Key result

Water solubility:

< 0 g/L

Temp.:

20 °C

Remarks on result:

other: Initial Nominal Loading Rate of 10 mg/L

Results

Main Test

The mean peak area ratios relating to the standard, sample and blank solutions are shown in the following tables:

 

Table 3.1– Nominal 100 mg/L Loading Rate

Solution	Mean Peak AreaRatio
Standard 12.3 mg/L	1.1025
Standard 12.5 mg/L	1.1377
Vessel 1 Sample 1	0.094700
Vessel 2 Sample 1	0.070662
Vessel 3 Sample 1	0.034166
Sample Blank	0.028235
Standard 12.0 mg/L	1.1359
Standard 11.6 mg/L	1.0828
Vessel 1 Sample 2	0.12385
Vessel 1 Sample 3	0.045714
Vessel 2 Sample 2	0.086710
Vessel 2 Sample 3	0.041093
Vessel 3 Sample 2	0.034924
Vessel 3 Sample 3	0.044094
Sample Blank	0.031124
Standard 10.7 mg/L	0.94819
Standard 11.8 mg/L	1.0050
Vessel 1 Sample 4	0.18342
Vessel 1 Sample 5	0.031441
Vessel 2 Sample 4	0.043331
Vessel 2 Sample 5	0.10310
Vessel 3 Sample 4	0.037796
Vessel 3 Sample 5	0.033121
Sample Blank	0.098785

 

Table 3.1– Nominal 100 mg/L Loading Rate - Continued

Solution	Mean Peak Area Ratio
Standard 10.4 mg/L	0.90695
Standard 11.1 mg/L	0.96049
Vessel 1 Sample 6	0.029381
Vessel 2 Sample 6	0.020824
Vessel 3 Sample 6	0.031843
Sample Blank	0.11007

 

Table 3.2– Nominal 10 mg/L Loading Rate

Solution	Mean Peak Area Ratio
Standard 12.3 mg/L	1.1025
Standard 12.5 mg/L	1.1377
Vessel 1 Sample 1	0.083834
Vessel 2 Sample 1	0.032294
Vessel 3 Sample 1	0.027888
Sample Blank	0.028235
Standard 12.0 mg/L	1.0961
Standard 11.6 mg/L	1.0333
Vessel 1 Sample 2	0.040130
Vessel 1 Sample 3	0.059563
Vessel 2 Sample 2	0.036098
Vessel 2 Sample 3	0.035493
Vessel 3 Sample 2	0.031781
Vessel 3 Sample 3	0.042231
Sample Blank	0.031124

 

 

  Table 3.2– Nominal 10 mg/L Loading Rate - Continued

Solution	Mean Peak Area Ratio
Standard 10.7 mg/L	0.92765
Standard 11.8 mg/L	1.0013
Vessel 1 Sample 4	0.063203
Vessel 1 Sample 5	0.023069
Vessel 2 Sample 4	0.037548
Vessel 2 Sample 5	0.020285
Vessel 3 Sample 4	0.039763
Vessel 3 Sample 5	0.022421
Sample Blank	0.098785
Standard 10.4 mg/L	0.90695
Standard 11.1 mg/L	0.96049
Vessel 1 Sample 6	0.058427
Vessel 2 Sample 6	0.025485
Vessel 3 Sample 6	0.020424
Sample Blank	0.11007

 

As the test item peaks covered a wide retention time range and there were peaks observed in the blank solutions over the same range, the concentration attributed to the blank was subtracted from the sample concentrations. 

 

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

 

Table 3.3– Nominal 100 mg/L Loading Rate, Vessel 1

Sample Number	Stirring / Equilibration Time (hours)	Concentration (g/L)	Solution pH
1	22.8	7.37 x 10^-6	6.90
2	44.1	9.85 x 10^-6	7.04
3	49.8	1.55 x 10^-6	6.70
4	68.2	9.73 x 10^-6	7.00
5	73.7	-7.75 x 10^-6	7.00
6	92.3	-9.28 x 10^-6	7.10

 

A variable, negligible quantity was detected in the retention time range of the test item in both samples and sample blank. The amount detected was well below the range investigated for the analysis. The result is therefore taken as less than the level at which successful detection of the test item was achieved. See validation and discussion in overall remarks and attachments section below.

 

Table 3.4– Nominal 100 mg/L Loading Rate, Vessel 2

Sample Number	Stirring / Equilibration Time (hours)	Concentration (g/L)	Solution pH
1	22.8	4.70 x 10^-6	6.99
2	44.1	5.91 x 10^-6	7.05
3	49.8	1.06 x 10^-6	6.74
4	68.2	-6.38 x 10^-6	6.74
5	73.7	4.96 x 10^-7	6.81
6	92.3	-1.03 x 10^-5	7.04

 

A variable, negligible quantity was detected in the retention time range of the test item in both samples and sample blank. The amount detected was well below the range investigated for the analysis. The result is therefore taken as less than the level at which successful detection of the test item was achieved.  See validation and discussion in overall remarks and attachments section below.

 

 

Table 3.5– Nominal 100 mg/L Loading Rate, Vessel 3

Sample Number	Stirring / Equilibration Time (hours)	Concentration (g/L)	Solution pH
1	22.8	6.58 x 10^-7	6.94
2	44.1	1.06 x 10^-6	6.92
3	49.8	4.04 x 10^-7	6.89
4	68.2	-7.01 x 10^-6	6.88
5	73.7	-7.55 x 10^-6	6.74
6	92.3	-9.00 x 10^-6	6.99

 

A variable, negligible quantity was detected in the retention time range of the test item in both samples and sample blank. The amount detected was well below the range investigated for the analysis. The result is therefore taken as less than the level at which successful detection of the test item was achieved.  See validation and discussion in overall remarks and attachments section below.

 

Table3.6– Nominal 10 mg/L Loading Rate, Vessel 1

Sample Number	Stirring / Equilibration Time (hours)	Concentration (g/L)	Solution pH
1	22.8	6.17 x 10^-6	7.00
2	44.1	1.14 x 10^-6	7.10
3	49.8	3.29 x 10^-6	6.80
4	68.2	-4.00 x 10^-6	6.69
5	73.7	-8.67 x 10^-6	6.92
6	92.3	-5.94 x 10^-6	7.06

 

A variable, negligible quantity was detected in the retention time range of the test item in both samples and sample blank. The amount detected was well below the range investigated for the analysis. The result is therefore taken as less than the level at which successful detection of the test item was achieved. See validation and discussion in overall remarks and attachments section below.

 

 

Table3.7– Nominal 10 mg/L Loading Rate, Vessel 2

Sample Number	Stirring / Equilibration Time (hours)	Concentration (g/L)	Solution pH
1	22.8	4.50 x 10^-7	7.09
2	44.1	6.90 x 10^-7	6.99
3	49.8	6.23 x 10^-7	6.71
4	68.2	-6.99 x 10^-6	6.91
5	73.7	-9.00 x 10^-6	6.84
6	92.3	-9.73 x 10^-6	6.88

 

A variable, negligible quantity was detected in the retention time range of the test item in both samples and sample blank. The amount detected was well below the range investigated for the analysis. The result is therefore taken as less than the level at which successful detection of the test item was achieved. See validation and discussion in overall remarks and attachments section below.

 

Table3.8– Nominal 10 mg/L Loading Rate, Vessel 3

Sample Number	Stirring / Equilibration Time (hours)	Concentration (g/L)	Solution pH
1	22.8	-3.85 x 10^-8	6.81
2	44.1	2.12 x 10^-7	6.91
3	49.8	1.37 x 10^-6	6.81
4	68.2	-6.73 x 10^-6	6.99
5	73.7	-8.75 x 10^-6	6.90
6	92.3	-1.03 x 10^-5	6.95

 

A variable, negligible quantity was detected in the retention time range of the test item in both samples and sample blank. The amount detected was well below the range investigated for the analysis. The result is therefore taken as less than the level at which successful detection of the test item was achieved. See validation and discussion in overall remarks and attachments section below.

 

 

The overall water solubility results for the two different loading rates evaluated are summarized in the following tables:

 

Table 3.9– Nominal 100 mg/L Loading Rate

Vessel	1	2	3
Mean Water Solubility (g/L at 20.0 ± 0.5 ºC)	< 1.15x 10^-4	< 1.15x 10^-4	< 1.15x 10^-4
Standard Deviation	not applicable	not applicable	not applicable
Relative Standard Deviation	not applicable	not applicable	not applicable

 

Overallwater solubility                             :         less than 1.15x 10^-4g/L at 20.0 ± 0.5 ºC

 

Table3.10– Nominal 10 mg/L Loading Rate

Vessel	1	2	3
Mean Water Solubility (g/L at 20.0 ± 0.5 ºC)	< 1.15x 10^-4	< 1.15x 10^-4	< 1.15x 10^-4
Standard Deviation	not applicable	not applicable	not applicable
Relative Standard Deviation	not applicable	not applicable	not applicable

 

Overall water solubility                             :         less than 1.15x 10^-4g/L at 20.0 ± 0.5 ºC  

Conclusions:

Please see the Conclusion within the Executive Summary Section below.

Executive summary:

The determination was carried out using a slow stiradaptation of the standard test method, based on thefindings of Letinski, D.J., Connolly, M.J., Peterson, D.R. and Parkerton, T.F. (2002) “Slow-stir water solubility measurements of selected alcohols and diesters”, Chemosphere 48, 257-265. The method employed was designedto be compatible with the data endpoint requirements of Method A6 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.

 

The slow-stir procedure was used as during a previous study (Harlan Study Number 41304207) using the flask method, it was identified that excess, undissolved test item could not be successfully excluded from the saturated solutions. The slow stir method eliminated dispersion of the test item throughout the solution and thus allowed isolation of saturated solutions free from excess, undissolved test item suitable for analysis.

 

Slow-stirring therefore enables the solubilisation of the test item without the formation of potentially problematic micro-droplets. The alternative column elution method proposed by the guidelines for addressing substances of low solubility is poorly suited to liquid test items.

 

As the test item is a UVCB substance, the effect of initial loading rate was also evaluated during the definitive determination of water solubility, using initial nominal loading rates of 100 mg/L and 10 mg/L, in order to assess if this affected either the resulting aqueous concentration or the composition of the dissolved fraction.

Conclusion

The water solubility of the test item at 20.0 ± 0.5 °C was evaluated using a slow stir adaptation of the standard test method. The results are summarized in the following table:

 

Table3.11

Initial Nominal Loading Rate	Water Solubility  (g/L of solution at 20.0 ± 0.5 °C)
100 mg/L	< 1.15x 10^-4
10 mg/L	< 1.15x 10^-4

 

Description of key information

Water solubility (whole substance): <0.1 mg/l at 20±0.5°C (read-across).

Water solubility (individual constituents): <1E-04 - 1.5E-01 mg/l at 20°C (QSAR)

Additional information

There is no data available for Hydrocarbons, C11-C16, n-alkanes, isoalkanes, <2% aromatics. However, data is available for structural analogues, Hydrocarbons, C12-C15, n-alkanes, isoalkanes, <2% aromatics; Hydrocarbons, C14-C16, n-alkanes, isoalkanes, <2% aromatics; and Hydrocarbons C15-C19, n-alkanes, isoalkanes, <2% aromatics and presented in the dossier. The hypothesis for the analogue approach is that the test substances, contain constituents which are also constituents of the target substance, Hydrocarbons, C11-C16, n-alkanes, isoalkanes, <2% aromatics. The substances have overlapping constituents and therefore have qualitatively similar properties (RAAF Scenario 2 applies).

There are no reliable measured water solubility data for the submission substance. However, reliable data are available for related substances in the relevant carbon number range.

The "whole substance" water solubilities of the related substances, Hydrocarbons, C10-C13, n-alkanes, isoalkanes, <2% aromatics (GS190), Hydrocarbons, C12-C15, n-alkanes, isoalkanes, <2% aromatics (GS215), Hydrocarbons, C14-C16, n-alkanes, isoalkanes, <25 aromatics (GS250) and Hydrocarbons, C15-C19, n-alkanes, isoalkanes, <2% aromatics (GS270) were evaluated using a slow-stir method. The method was designed to be compatible with EU Method A.6 and OECD 105. Since the test substances are a UVCBs, the effect of initial loading rate was also evaluated during the definitive study using initial nominal loading rates of 100 mg/l and 10 mg/l to assess if the resulting aqueous concentration or composition of the dissolved fraction were affected. The water solubility of GS190, GS215, GS250 and GS270 was determined to be <0.1 mg/l at 20±0.5°C at both the 100 mg/l and 10 mg/l loading rates. The results are considered to be reliable and are used as weight of evidence.

As supporting information, the water solubility of each constituent has also been predicted using a separately validated QSAR estimation method. The prediction method uses a fragment method and water solubility decreases with increasing carbon number. The prediction domain covers carbon chain length in the range C2-C15 carbon atoms, it is therefore expected that water solubility for longer chain length (i.e. greater than C15) compounds will be lower than the predicted value for C15 atom. Thus the water solubility of the individual constituents is in the range <1E-04 mg/l - 1.5E-01 mg/l at 20°C.