Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Physical & Chemical properties

Partition coefficient

Currently viewing:

Administrative data

Link to relevant study record(s)

Reference
Endpoint:
partition coefficient
Type of information:
experimental study
Adequacy of study:
key study
Study period:
from 2017-11-17 to 2018-01-18
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)
Deviations:
no
Qualifier:
according to guideline
Guideline:
EU Method A.8 (Partition Coefficient - HPLC Method)
Version / remarks:
EU Method A.24, EC 2016/266, 01.03.2016
Deviations:
no
Qualifier:
according to guideline
Guideline:
EPA OPPTS 830.7570 (Partition Coefficient, n-octanol / H2O, Estimation by Liquid Chromatography)
Deviations:
no
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:
< 0.3
Temp.:
20 °C
pH:
7.78
Details on results:
The pH of the 200 μg/mL test item solution was 7.78 in ultrapure water.

Calibration

The partition coefficient Pow was determined based on a calibration curve using seven reference items.

The capacity factors (k) were calculated from the dead time and retention times of the reference substances.

The equation of the curve fitted to the calibration points is as follows:

log k = 0.252 * log Pow - 0.592 (Rsq = 0.99)

Determination

As the test item is an UVCB substance, its constituents were determined with the HPLC-MS.

Retention time measured for the identified components of the test item (3.21, 3.27 and 4.36 min for Mono-, Di- and Bis ester respectively) is lower than the retention time of the first eluting standard (2-Butanone 5.50 min). This result clearly shows that log Pow of the constituents of the test item is lower than the calibrated range.

Using the HPLC method the log Pow of the constituents of the test item was determined to be < 0.3.

An impurity was detected with HPLC-UV (retention time 22.69 min). This impurity is regarded as insignificant as the respective HPLC-MS results show that the area compared to the other constituents is several magnitudes lower than the main constituents. Thus, this peak was not evaluated in detail.

Table 2. Measured and calculated data of the components of the test item

Components

Retention time (min)

Log Pow

Phosphoric acid mono(2-ethylhexyl) ester

3.21

3.21

3.21

3.21

3.21

3.20

-

Mean (CV%)

3.21 (0.13)

-

Pyrophosphoric acid di(2-ethylhexyl) ester

3.30

3.27

3.29

3.26

3.25

3.22

-

Mean (CV%)

3.27 (0.88)

-

Phosphoric acid bis(2-ethylhexyl) ester

4.37

4.37

4.36

4.36

4.36

4.36

-

Mean (CV%)

4.36 (0.12)

-

Conclusions:
Using the HPLC method the log Pow of the constituents of the test item was determined to be < 0.3.
Executive summary:

A study was conducted in accordance with OECD TG 117, Regulation (EC) No 440/2008 method A.24 and OPPTS 830.7570 to determine the partition coefficient of the test substance using the HPLC-UV/MS method. A solution of the test substance was prepared in acetonitrile at concentration level of 200 mg/L. Three series of the reference solutions and three series of the test item solution with two parallel injections were alternately measured. The constituents of the test item were determined using HPLC-MS. Retention time measured for the identified components of the test item (3.21, 3.27 and 4.36 min for Mono-, Di- and Bis ester respectively) was lower than the retention time of the first eluting standard (2-Butanone 5.50 min). This result clearly showed that log Pow of the constituents of the test item is lower than the calibrated range. Using the HPLC method the log Pow of the constituents of the test item was determined to be < 0.3. An impurity was detected with HPLC-UV (retention time 22.69 min) which was regarded as insignificant as the respective HPLC-MS results showed that the area compared to the other constituents is several magnitudes lower than the main constituents. Thus, this peak was not evaluated in detail.

Description of key information

Using the HPLC method the log Pow of the constituents of the test item was determined to be < 0.3.

Key value for chemical safety assessment

Additional information

A study was conducted in accordance with OECD TG 117, Regulation (EC) No 440/2008 method A.24 and OPPTS 830.7570 to determine the partition coefficient of the test substance using the HPLC-UV/MS method. A solution of the test substance was prepared in acetonitrile at concentration level of 200 mg/L. Three series of the reference solutions and three series of the test item solution with two parallel injections were alternately measured. The constituents of the test item were determined using HPLC-MS. Retention time measured for the identified components of the test item (3.21, 3.27 and 4.36 min for Mono-, Di- and Bis ester respectively) was lower than the retention time of the first eluting standard (2-Butanone 5.50 min). This result clearly showed that log Pow of the constituents of the test item is lower than the calibrated range. Using the HPLC method the log Pow of the constituents of the test item was determined to be < 0.3. An impurity was detected with HPLC-UV (retention time 22.69 min) which was regarded as insignificant as the respective HPLC-MS results showed that the area compared to the other constituents is several magnitudes lower than the main constituents. Thus, this peak was not evaluated in detail.