Phosphoric acid, 2-ethylhexyl ester, sodium salt

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2017-12-15

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 107 (Partition Coefficient (n-octanol / water), Shake Flask Method)

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

no

Type of method:

flask method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

Key result

Type:

log Pow

Partition coefficient:

-1

Temp.:

20 °C

pH:

6.73

Remarks on result:

other: monoester

Key result

Type:

log Pow

Partition coefficient:

1.11

Temp.:

20 °C

pH:

6.73

Remarks on result:

other: diester

Solubility of component 1 and component 2 in the 1-octanol phases 

Flask	Area component 1	mg/L component 1	Area component 2	mg/L component 2
Oct 1	51256	155.8	6683215	1227.8
Oct 2	95462	85.6	13590805	1101.8
Oct 3	19114	72.3	13175791	1074.2
Oct 4	21745	72.8	13810190	1116.3
Oct 5	3226	139.2	5334194	1020.8
Oct 6	8721	70.5	13371229	1087.2

 

 

Solubility of component 1 and component 2 in the water phases: 

Flask	Area component 1	mg/L component 1	Area component 2	mg/L component 2
WEM 1	7474081	2128.2	7198	132.4
WEM 2	6806426	1982.7	9066	132.7
WEM 3	6149288	917.6	26531	67.9
WEM 4	6395438	945.5	27997	68.1
WEM 5	2448064	451.2	30506	68.3
WEM 6	2442200	422.0	33210	68.5

 

With the previous results for water and 1-octanol solubility, the determination of the partition coefficient of component 1 and component 2 are listed below:

 

Calculation of the log Pow of component 1 (monoester):

Flask	Phase	Concentration mg/L	log Pow	Average log Pow	Standard Deviation
1	1-Octanol	155.8	-1.14	-1.00	±0.3
	Water	2128.2
2	1-Octanol	85.6	-1.37
	Water	1982.7
3	1-Octanol	72.3	-1.1
	Water	917.6
4	1-Octanol	72.8	-1.11
	Water	945.5
5	1-Octanol	139.2	-0.51
	Water	451.2
6	1-Octanol	70.5	-0.78
	Water	422

 

Calculation of the log Pow of component 2 (diester):

Flask	Phase	Concentration mg/L	log Pow	Average log Pow	Standard Deviation
1	1-Octanol	1227.8	0.97	1.11	± 0.13
	Water	132.4
2	1-Octanol	1101.8	0.92
	Water	132.7
3	1-Octanol	1074.2	1.2
	Water	67.9
4	1-Octanol	1116.3	1.21
	Water	68.1
5	1-Octanol	1020.8	1.17
	Water	68.3
6	1-Octanol	1087.2	1.2
	Water	68.5

 

 

 

Conclusions:

The logPow of the two main constituents were determined to be logPow -1.00 for the monoester and logPow 1.11 for the diester.

Executive summary:

A study was conducted in accordance with OECD TG 107 and Regulation (EC) No 440/2008 method A.8 to determine the partition coefficient of the test substance using the shake flask method. In 6 flasks amounts of stock solution were served and filled with 1-Octanol saturated water. The flasks were shaken on a mechanical shaker for 30 minutes at 320 1/min and then allowed to stand for phase separation. The samples were worked up and analysed with HPLC-ELSD. The logPow of the two main constituents were determined to be logPow -1.00 for the monoester and logPow 1.11 for the diester.

Description of key information

The logPow of the two main constituents were determined to be logPow -1.00 for the monoester and logPow 1.11 for the diester. The logPow of 1.11 was chosen as the key value and is used for further risk assessment.

Key value for chemical safety assessment

Log Kow (Log Pow):

1.11

at the temperature of:

20 °C

Additional information

A study was conducted in accordance with OECD TG 107 and Regulation (EC) No 440/2008 method A.8 to determine the partition coefficient of the test substance using the shake flask method. In 6 flasks amounts of stock solution were served and filled with 1-Octanol saturated water. The flasks were shaken on a mechanical shaker for 30 minutes at 320 1/min and then allowed to stand for phase separation. The samples were worked up and analysed with HPLC-ELSD. The logPow of the two main constituents were determined to be logPow -1.00 for the monoester and logPow 1.11 for the diester.