Reaction mass of ammonium dodecyl sulfate, ammonium tetradecyl sulfate and ammonium alkoxy-alkyl sulfate

Partition coefficient

Administrative data

Endpoint:

partition coefficient

Type of information:

calculation (if not (Q)SAR)

Adequacy of study:

key study

Study period:

23 Nov 2016

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

accepted calculation method

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2016

Report date:

2016

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: Computational Approach in OECD Guideline 107 (EU A.8)

Principles of method if other than guideline:

According to the guidance of the ECHA a ratio calculation is an acceptable alternative for the determination of octanol/water Partition Coefficient of surfactants.
Citation from ''Guidance on information requirements and chemical safety assessment Chapter R.7a: Endpoint specific guidance'', R.7.1.8 Partition Coefficient, page 102:
This method enables partition coefficient to be calculated based on the ratio of the solubility of the material in octanol and water. For some substances (e.g. some surfactants and pigments), it is technically not feasible (or good practice) to measure an octanol-water partition coefficient by OECD 107, and other methods (OECD 117 and QSAR) may be unsuitable as they are based on extrapolations of measured values. For such substances it may be possible to obtain a ratio of the saturated water solubility (OECD 105) and saturated octanol solubility (no guideline currently available but based on the principles of OECD 105). The calculation method however has the drawback that it does not include the interaction between the water and solvent phase (i.e. a chemical with high Pow is rather ‘pushed out of the water’ than ‘pulled into octanol’). This explains the poor correlation typically observed between octanol solubility and Kow (Dearden, 1990, Sijm et al., 1999). The ratio was found somewhat more representative if one uses octanol/saturated water and water/saturated octanol.

GLP compliance:

no

Type of method:

other: calculated

Partition coefficient type:

octanol-water

Test material

Test material information

Constituent 1

Reference substance name:

Reaction mass of ammonium dodecyl sulfate, ammonium tetradecyl sulfate and ammonium alkoxy-alkyl sulfate

Molecular formula:

n.a. (UVCB substance)

IUPAC Name:

Reaction mass of ammonium dodecyl sulfate, ammonium tetradecyl sulfate and ammonium alkoxy-alkyl sulfate

Test material form:

solid

Results and discussion

Partition coefficient

Key result

Type:

log Pow

Partition coefficient:

1

Temp.:

20 °C

pH:

4.4

Any other information on results incl. tables

n-Octanol solubility of the test item: 99.26 g/L at 20 °C

Water solubility of the test item: 9.80 g/L at 20 °C

P_ow = 99.26/9.8 = 10.129; log Pow = 1.0.