Docusate sodium

Solubility in organic solvents / fat solubility

Administrative data

Endpoint:

solubility in organic solvents / fat solubility

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2010

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2010

Report date:

2010

Materials and methods

Test guideline

Test guideline 1

Qualifier:

equivalent or similar to guideline

Guideline:

other: EU A.6

Test guideline 2

Qualifier:

equivalent or similar to guideline

Guideline:

other: Slow-stir method as referred in the ECHA document 'Guidance on information requirements and chemical safety assessment, Chapter R.7a: Endpoint specific guidance' (May 2008)

Principles of method if other than guideline:

The solubility of Docusate Sodium in n-octanol at 20 °C was investigated in analogy to the slow-stir method
as referred in the ECHA document 'Guidance on information requirements and chemical safety assessment,
Chapter R.7a: Endpoint specific guidance' (May 2008). Basic principles and requirements of the water solubility
method EC A.6 were followed.

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

Docusate sodium

EC Number:

209-406-4

EC Name:

Docusate sodium

Cas Number:

577-11-7

Molecular formula:

C20H38O7S.Na

IUPAC Name:

sodium 1,4-bis[(2-ethylhexyl)oxy]-1,4-dioxobutane-2-sulfonate

Details on test material:

- Name of test material (as cited in study report): Docusate Sodium / AEROSOL® OT-100% Surfactant
- Substance type: detergent
- Physical state: colourless solid, shape of thin layers wrapped like a bolt
- Analytical purity:>97 %
- Impurities (identity and concentrations):
Water (CAS 7732-18-5), <2 %
2-Ethylhexanol (CAS 104-76-7), <1 %
Bis(2-ethylhexyl)maleate (CAS 142-16-5), <0.5 %
Sodium sulfate (CAS 7757-82-6), <0.5 %
Sodium bisulfite (CAS 7631-90-5), <0.2 %
- Lot/batch No.: SU9091805

Results and discussion

Solubility in organic solvents / fat solubility

Medium:

n-octanol

Solubility:

814 g/L

Temp.:

20 °C

Test substance stable:

yes

Any other information on results incl. tables

 

Parameter Solution I Solution II Solution III Piece cut out for analysis [mg] 364.0 272.2 286.3 Volume of ethanolic solution [mL] 50 50 50 concentration of ethanolic solution [g/L] Measurement I 5.639 4.316 4.485 Measurement II 5.709 4.299 4.530 Concentration of saturated solution in n-octanol [g/L] Measurement I 828.8 848.3 838.1 Measurement II 839.1 845.0 846.5

 

The highest result of the n-octanol solubility differed from the lowest one by less than 15%. Therefore all results were used for further

calculations. The solubility of the test substance in n-octanol at 20 °C was obtained by calculating the mean value of all results. The mean value is 841 g/l.

The most important contribution to the uncertainty of the result comes from the distribution of analytical measurements. The standard deviation of the results was calculated to be 7 g/l, giving an expanded uncertainty of 14 g/l (coverage factor k=2). An additional contribution to the uncertainty of the solubility arises from the fact that the test substance might be contaminated by sulfur containing compounds (see composition chap. 2.4). Unfortunately, there are to many unknown parameters related to this problem in order to discuss the contribution to the uncertainty on a theoretical basis. These parameters are for example the true content of each of these contaminations, the solubility of the contaminations in the presence of the main component, the influence of the

contaminations on the solubility of the main component etc.

Thus the final result for the solubility of Docusate sodium in n-octanol at 20 °C is 841 ± 14 g/l.

Applicant's summary and conclusion

Conclusions:

The n-octanol solubility is 814 g/L

Executive summary:

The n-octanol water solubility of Docusate Sodium at 20 °C was investigated by the slow-stir method as referred in the ECHA document 'Guidance on information requirements and chemical safety assessment, Chapter R.7a: Endpoint specific guidance' (May 2008). Basic principles and requirements of the established method EC A.6 were followed. The concentration in the saturated solution was determined by XRF measurement to be 814 ± 14 g/l..

The results of this study are considered to be acceptable for the risk assessment.