Registration Dossier

Administrative data

Endpoint:
water solubility
Type of information:
experimental study
Adequacy of study:
key study
Study period:
Testing was conducted between 16 May 2008 and 13 June 2008.
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Study conducted to GLP and in compliance with agreed protocols, with no or minor deviations from standard test guidelines and/or minor methodological deficiencies, which do not effect the quality of the relevant results.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2008
Report Date:
2008

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
EU Method A.6 (Water Solubility)
Deviations:
no
GLP compliance:
yes (incl. certificate)
Remarks:
The work described was performed in compliance with UK GLP standards (Schedule 1, Good Laboratory Practice Regulations 1999 (SI 1999/3106 as amended by SI 2004/0994)).
Type of method:
flask method

Test material

Reference
Name:
Unnamed
Type:
Constituent

Results and discussion

Water solubility
Water solubility:
86.5 g/L
Temp.:
20 °C
pH:
ca. 7.6

Any other information on results incl. tables

                  Preliminary test

Observations, concentrations and pH relating to the samples are shown in the following table:

Sample

Concentration

(% w/w)

Observation

pH

1

10.0

Clear, colourless solution, with a slight excess of undissolved test material.

8.1

2

20.1

Clear, colourless solution, with much excess undissolved test material.

7.8

3

30.0

Hazy liquid, but more excess undissolved test material.

7.8

4

39.9

Hazy liquid, but more excess undissolved test material.

7.9

5

60.0

Dampened test material only.

*

* not measured due to the nature of the sample

The preliminary estimate of water solubility was approximately 10 % w/w of solution.

Definitive test

The absorbances relating to the standard and sample solutions are shown in the following table:

Solution

Absorbance

Standard 26.3 mg/l

0.793

Standard 25.4 mg/l

0.766

Matrix blank

None detected

Sample 1A

1.057

Sample 1B

1.065

Sample 3A

1.030

Sample 3B

1.027


The concentration (g/l) of test material in the sample solutions is shown in the following table:

Sample Number

Time Shaken at

~ 30ºC (hours)

Time Equilibrated at 20ºC (hours)

Concentration (g/l)

Solution pH

1

24

24

87.9

7.6

3

72

24

85.2

7.6

Mean concentration:     86.5 g/l at 20.0 ± 0.5ºC
Range:                          85.2 to 87.9 g/l

Validation

The linearity of the detector response with respect to concentration was assessed over the nominal concentration range of 0 to 50 mg/l.  This was satisfactory with a correlation coefficient of 0.999 being obtained.

Discussion

Sample 2 was lost when the centrifuge tube broke whilst the sample was being centrifuged. However, the results for Samples 1 and 3 indicate that solution saturation was attained after 24 hours shaking. Therefore, calculating the water solubility as the mean of Samples 1 and 3 was considered valid.

Conclusion

The water solubility of the test material has been determined to be 86.5 g/l of solution at 20.0 ± 0.5°C.


Applicant's summary and conclusion

Conclusions:
Interpretation of results (migrated information): very soluble (> 10000 mg/L)
The water solubility of the test material has been determined to be 86.5 g/l of solution at 20.0 ± 0.5°C.
Executive summary:

For substance Na-Na in project number 1307-0436 the water solubility of the test material has been determined to be 86.5 g/l of solution at 20.0 ± 0.5°C by using the flask method, Method A6 of Commission Directive 92/69/EEC (which constitutes Annex V of Council Directive 67/548/EEC).