Ammonium benzoate

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

17. May 2017 - 01. June 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)

Qualifier:

according to guideline

Guideline:

EU Method A.8 (Partition Coefficient - HPLC Method)

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: 608031
- Expiration date of the lot/batch: 25. Oct. 2018
- Purity test date: not stated

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Room temperature
- Stability under test conditions: assumed stable
- Solubility and stability of the test substance in the solvent/vehicle: soluble in alcohol and water and assumed stable
- Reactivity of the test substance with the solvent/vehicle of the cell culture medium: not expected

TREATMENT OF TEST MATERIAL PRIOR TO TESTING
none

Analytical method:

high-performance liquid chromatography

photometric method

Key result

Type:

log Pow

Partition coefficient:

< 0.3

Temp.:

25 °C

pH:

> 5 - < 6

Type:

log Pow

Partition coefficient:

ca. -0.399

Temp.:

25 °C

pH:

> 5 - < 6

Remarks on result:

other: calculated result based on Equation of regression

Conclusions:

Due to the fact that the calculated log POW of the test item lay outside the calibrated range
(0.30 – 2.70) the log POW of Ammonium Benzoate is stated as < 0.3.

Executive summary:

The study was performed using a HPLC with a C18 column. Six reference items with different

retention times and thiourea for the determination of the dead time were used to

produce a calibration curve, since retention time on hydrophobic columns and POW are

correlated. The reference items were chosen based on the results of the pre-test.

One vial was filled with the reference item mix and one vial with the test item solution. The

vials were analysed using the HPLC with the program described in chapter 6.3.2. First one

injection from the solvent blank methanol/water 65/35 (v/v) was made. Then three injections

were measured from the reference item mix, three injections from the test item and

again three injections from the reference item mix.

For each reference item, the capacity factor k was calculated from the retention time of

thiourea and the retention time of the respective reference item.

A calibration function (log k versus log POW, linear fit) was determined using the literature

values for POW of the reference items and the retention times in the six determinations.

The chromatogram of the test item gave one peak. With the calibration function log k versus

log POW, the corresponding log POW value of the test item peak was determined with:

-0.399 ± 0.026

This value is the mean ± standard deviation of three independent determinations.

Due to the fact that the calculated log POW of the test item lay outside the calibrated range

(0.30 – 2.70) the log POW of Ammonium Benzoate is stated as < 0.3.

Description of key information

one Guideline study performed. For assessment, the calculated value based on the equation of regression is used.

Key value for chemical safety assessment

Log Kow (Log Pow):

-0.399

at the temperature of:

25 °C