Benzene, 1,1'-oxybis[methyl-, sulfonated, ammonium salts

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

15 - 16 September 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 117 (Partition Coefficient (n-octanol / water), HPLC Method)

Version / remarks:

2004

Deviations:

yes

Remarks:

see field principle of method if other than guideline

Qualifier:

according to guideline

Guideline:

EU Method A.8 (Partition Coefficient - Shake Flask Method)

Version / remarks:

Regulation (EC) No 440/2008

Deviations:

yes

Remarks:

see field principle of method if other than guideline

Principles of method if other than guideline:

According to TG OECD 117, log Pow values between 0 and 6 can be determined. As the test item is a complex mixture, a broad range of log Pow values has been found and some of the test item components are out of the range of 0 to 6. In accordance with the sponsor, the log Pow values for these test item components were extrapolated based on the data obtained in this study.
According to TG OECD 117, upper and lower limits of log Pow, and the area% of each log Pow peak should be reported for mixtures, which result in an unresolved band. For the test item in this study, only upper and lower limits of log Pow are given, because single log Pow peaks can hardly be assigned in this complex mixture.

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

Key result

Type:

log Pow

Partition coefficient:

ca. -1.08 - <= 2.35

Temp.:

25 °C

pH:

7

Remarks on result:

other: log Pow range: <= -1.08 to 2.35; mean of two determinations

Details on results:

HPLC method:
The dead time was determined to be 1.45 min.

Two determinations of the log POW value of the test item were conducted using a phosphate buffered system at pH 7.0 by injecting a mixed solution of all reference items as well as the single test item solution twice.
The test item “Benzene, 1,1’-oxybis(methyl-, sulfonated, ammonium salt (ca 50% )” is a complex mixture of monomer until pentamer, which present one or two sulfo groups and each type of substance presents several isomer forms. Therefore, the log Pow is given as a range, which is based on the evaluation of the first and the last test item peak found in the corresponding chromatogram.
The log Pow value for the first test item peak with the shortest retention time was extrapolated. As its retention time was slightly shorter than the one for Thiourea, which was used as dead time marker, an extrapolation based on the regression data obtained by the injection of reference items was not possible. Instead, its log Pow can be given as less than or equal to the one of Thiourea corresponding to <= -1.08 (exper. database match; Govers H. et al., (1986); EPI Suite v4.11).
The log Pow value for the last test item peak with the latest retention time was determined to be 2.35 (95% confidence limits: 2.25–2.45) in the first as well as the second determination.
Consequently, the log Pow range for the test item “Benzene, 1,1’-oxybis(methyl-, sulfonated, ammonium salt (ca 50% )” (CAS no. of main component 75314-26-0), calculated as the mean of both determinations, is <= -1.08 to 2.35 (95% confidence limits for upper value: 2.25–2.45) at pH 7.0.

Test item component with maximal logPow:

Regression for the determination of the log Pow value of the test item with the first injection

Plot log Pow vs log k:

coefficient of regression (r^2)	0.996
intercept	0.397
slope	1.38
log Pow	2.35
95% confidence interval for log Pow	2.25 -2.45

Regression for the determination of the test item with the second injection

Plot log POW vs log k:

coefficient of regression (r^2)	0.996
intercept	0.398
slope	1.38
log POW	2.35
95% confidence interval for log POW	2.25 -2.45

Conclusions:

The HPLC method was applied for the determination of the log Pow of Benzene, 1,1’-oxybis(methyl-, sulfonated, ammonium salt (ca 50% ) (CAS no. of main component 75314-26-0).
The calculated log Pow range of the test item is <=1.08 to 2.35 (95% confidence limits for upper value: 2.25-2.45) at a pH of 7.0.

Executive summary:

The log Pow of the test item „Benzene, 1,1’-oxybis(methyl-, sulfonated, ammonium salt (ca 50% )” (CAS no. of main component 75314-26-0) was determined according to TG OECD 117. This determination is based upon a regression analysis of the log Pow values of reference items against their respective retention times as determined by HPLC analysis. As the test item is a complex mixture, the log Pow is given as a range, which is based on the evaluation of the first and the last test item peak found in the corresponding chromatogram.

The following reference items were used: Caffeine, 4-Acetylpyridine, Aniline, Acetophenone, Nitrobenzene, Anisole and Chlorobenzene. The dead time of the HPLC system was determined with Thiourea.

This set of reference items yielded a calibration with log Pow values ranging from -0.07 to 2.8 and retention times ranging from 2.19 min to 75.6 min. The dead time of the HPLC system was 1.45 min.

Two determinations of the log Pow value of the test item were conducted using a phosphate buffered system at pH 7.0 by injecting a mixed solution of all reference items as well as the single test item solution twice.

The log Pow value for the first test item peak with the shortest retention time was extrapolated. As its retention time was slightly shorter than the one for Thiourea, which was used as dead time marker, an extrapolation based on the regression data obtained by the injection of reference items was not possible. Instead, its log Pow can be given as less than or equal to the one of Thiourea corresponding to <= -1.08 (exper. database match; Govers H. et al., (1986); EPI Suite v4.11).

The log Pow value for the last test item peak with the latest retention time was determined to be 2.35 (95% confidence limits: 2.25–2.45) in the first as well as the second determination.

Consequently, the log Pow range for the test item “Benzene, 1,1’-oxybis(methyl-, sulfonated, ammonium salt (ca 50% )”, calculated as the mean of both determinations, is <= -1.08 to 2.35 (95% confidence limits for upper value: 2.25–2.45) at pH 7.0.

Description of key information

The log POW of the test item Benzene, 1,1’-oxybis(methyl-, sulfonated, ammonium salt (ca 50% ) (CAS no. of main component 75314-26-0) was determined according to TG OECD 117. This determination is based upon a regression analysis of the log POW values of reference items against their respective retention times as determined by HPLC analysis. As the test item is a complex mixture, the log POW is given as a range, which is based on the evaluation of the first and the last test item peak found in the corresponding chromatogram.

Two determinations of the log POW value of the test item were conducted using a phosphate buffered system at pH 7.0 by injecting a mixed solution of all reference items as well as the single test item solution twice.

The log POW range for the test item Benzene, 1,1’-oxybis(methyl-, sulfonated, ammonium salt (ca 50% ), calculated as the mean of both determinations, is =-1.08 to 2.35  (95% confidence limits for upper value: 2.25–2.45) at pH 7.0.

Additional information

log Pow range -1.08 to 2.35 at pH 7.0