Registration Dossier

Diss Factsheets

Administrative data

Endpoint:
partition coefficient
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2018
Report date:
2018

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
OECD Guideline 117 (Partition Coefficient (n-octanol / water), HPLC Method)
GLP compliance:
no
Type of method:
HPLC method
Partition coefficient type:
octanol-water

Test material

Constituent 1
Chemical structure
Reference substance name:
Sodium toluene-4-sulphinate
EC Number:
212-538-5
EC Name:
Sodium toluene-4-sulphinate
Cas Number:
824-79-3
Molecular formula:
C7H8O2S.Na
IUPAC Name:
sodium toluene-4-sulphinate
Test material form:
solid

Study design

Analytical method:
high-performance liquid chromatography

Results and discussion

Partition coefficient
Key result
Type:
log Pow
Partition coefficient:
-0.9
Temp.:
23 °C
pH:
4
Details on results:
Preliminary visual estimation of the n-octanol solubility
Defined amounts of the test item were stirred with n-octanol at room temperature and visually checked for any undissolved parts. According to this preliminary test the solubility of the test item in n-octanol was between 1.6 g/l and 21.9 g/l (without correction for the purity).

Calculation of the partition coefficient log POW from the preliminary test
The estimated partition coefficient was calculated with the water solubility from the preliminary test data determined in project PS20180189-4 (cS = 212 g/l) . It was calculated to be: log POW between -1.0 and -2.1.
Also the program KOWWIN (part of EPI Suite) was used for calculating the log POW of the test item. The calculated values were -0.6 (for the free acid of the test item) and -2.5 (for the sodium salt of the test item).
Because of the estimated and the calculated values of log Pow, according to the guidelines the partition coefficient of the test item was determined by the shake flask method.

Partition coefficients of the shake flask method at pH 4 was determined to be log Pow = -0.9.

Applicant's summary and conclusion

Conclusions:
The partition coefficient (n-octanol/water) of the test item was determined: log Pow = -0.9 (pH 4).