2,3,4-trihydroxybenzophenone

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2016-02-08 to 2016-02-10

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)

Version / remarks:

2008

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:

2.8

Temp.:

23 °C

pH:

ca. 5.3

Calculation of partition coefficient
The program KOWWIN was used to calculate the partition coefficient. The calculated value was 2.9, therefore the shake flask method was used.

 

Shake Flask Method

A specified test item amount was dissolved in 100 mL n-octanol (saturated with distilled water). 10 mL of this solution were added to 6 different flasks (experiment 1A, 1B, 2A, 2B, 3A, 3B). Then, different amount of n-octanol (saturated with distilled water) and 20 mL distilled water (saturated with n-octanol) were added to the flasks. All mixtures were shaken for several minutes at 23 °C. After phase separation, each phase was centrifuged (30 min at 23 °C and 15000 rpm). Analytical samples were prepared and concentrations of the test item in the different phases were determined by HPLC.

Table 1 – Test conditions and results of shake flask method

Experiment	1A	1B	2A	2B	3A	3B
Test item amount [mg]	18.0
Concentration of the stock solution [mg/L]	180
Volume of added stock solution [mL]	10
Volume of added n-octanol [mL]	0		10		30
Volume of added distilled water [mL]	20
pH of aqueous phase at 23 °C	5.3		5.4	5.3	5.4	5.3
Measured concentration in aqueous phase [mg/L]	0.13 0.12	0.12 0.12	< 0.08 < 0.08		< 0.08 < 0.08
Mean concentration in aqueous phase [mg/L]*	0.25	0.24	< 0.16		< 0.16
Measured concentration in n-octanol phase [mg/L]	1.66 1.66	1.65 1.65	0.77 0.77	0.78 0.78	0.35 0.32	0.32 0.32
Mean concentration in n-octanol phase [mg/L]*	166.0	164.6	77.2	78.3	33.7	32.3

*for mean concentration the sample preparation (dilution) is taken into account

 

Given values of the concentrations in the aqueous and n-octanol phases are mean values of two measurements. The partition coefficients below are calculated from the measured and unrounded concentration values and not from the rounded values given in Table 1.

 

Table 2 – Partition Coefficients of shake flask method

Experiment	POW	log POW	Average log POW
1A	676.7	2.8	2.8
1B	696.2
2A	>487.6	>2.7	>2.7
2B	>494.1
3A	>212.5	>2.3	>2.3
3B	>204.2

 

In the experiments 2A to 3B the test item concentration in the aqueous phase was below the detection limit. Therefore, the partition coefficient determined in 1A and 1B were taken as the final result.

 

The partition coefficient log P_OW of the test item at 23 °C was determined to be 2.8.

Conclusions:

The partition coefficient log POW of the test item at 23 °C was determined to be 2.8.

Executive summary:

A study was conducted in accordance with OECD 107 and Regulation (EC) No 440/2008 method A.8 to determine the partition coefficient of the test substance using the shake flask method. The partition coefficient P_OW is defined as the ratio of the equilibrium concentrations of a dissolved test item in the two-phase system consisting of n-octanol and water. The partition coefficient P_OW is dimensionless and usually given in the form of its logarithm to base ten. The partition coefficient (n-octanol/water) of the test item was determined at room temperature (23°C) to be: log P_OW = 2.8.

Description of key information

The partition coefficient log P_OW of the test item at 23 °C was determined to be 2.8.

Key value for chemical safety assessment

Log Kow (Log Pow):

2.8

at the temperature of:

23 °C

Additional information

A study was conducted in accordance with OECD 107 and Regulation (EC) No 440/2008 method A.8 to determine the partition coefficient of the test substance using the shake flask method. The partition coefficient P_OW is defined as the ratio of the equilibrium concentrations of a dissolved test item in the two-phase system consisting of n-octanol and water. The partition coefficient P_OW is dimensionless and usually given in the form of its logarithm to base ten. The partition coefficient (n-octanol/water) of the test item was determined at room temperature (23°C) to be: log P_OW = 2.8.