tetrasodium 4-{4-[(9,10-dioxo-4-{[4-(2-sulfophenoxy)phenyl]amino}-9,10-dihydroanthracen-1-yl)amino]phenoxy}benzene-1-sulfonate 4-{4-[(9,10-dioxo-4-{[4-(4-sulfophenoxy)phenyl]amino}-9,10-dihydroanthracen-1-yl)amino]phenoxy}benzene-1-sulfonate

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2014

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:

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

Deviations:

no

GLP compliance:

no

Type of method:

flask method

Partition coefficient type:

octanol-water

Specific details on test material used for the study:

Identification: FAT 21030/E TE
Lot: AT-0027801200
Appearance: Dark green powder

Analytical method:

photometric method

Key result

Type:

log Pow

Partition coefficient:

-2.51

Temp.:

20 °C

Remarks on result:

other: pH not specified

Preliminary visual estimation of the n-octanol solubility:

10 mg of the test item were stirred with different amounts of n-octanol at room temperature and visually checked for any undissolved particles. According to this preliminary test the solubility of the test item in n-octanol is below 20 mg/l (without correction of the purity).

Table: Appearance of the test mixtures

Amount of test item in mg	Volume in mL	Total volume in mL	Stirring time	Appearance of mixture
10	50	50	60 min	undissolved
1	50	50	60 min	undissolved

Calculation of the partition coefficient log Pow from the preliminary tests:

The partition coefficient Pow may be estimated from the saturation concentrations in n-octanol and water by the following equation:

Pow = Cs octanol / Cs water

s= saturation

With the data obtained in the above section (cs < 20 mg/l) and in the preliminary test (water solubility: cs = 7.7 g/l), the partition coefficient was calculated as log POW <-2.5.

Due to the fact, that the partition coefficient from the estimation of the individual solubilities is below -2, the partition coefficient n-octanol/water has to be estimated from the individual solubilities in water and n-octanol.

Determination of the solubility in the n-octanol phase: Flask Method

Table: Solubility of the test item – Experiments A to D 

Experiment	A	B	C	D (blank)
Amount of test item (mg)	100	100	100	--
Stirring time at 30°C (h)	24	48	72	72
Measured concentration (µg/ml)	15.9	26.0	29.8	--
Solubility(mg/l)	15.9	26.0	29.8	--

 Average experiments A to C: 23.9 mg/l

 

Table: Concentrations of the standards for recheck:

Standard	Measured Concentration (µg/ml)	% Recovery
Sample C + 21.28 µg test item	40.59	99.8

The recovery of 99.8 % indicates a sufficient accuracy of the analytical method.

Calculation of the partition coefficient log Pow from the individual solubilities:

By means of the flask method, the saturation concentration of the test item in n-octanol was determined to: 23.9 mg/l.

By means of the flask method, the saturation concentration of the test item in water was determined to: 7.7 g/l

Pow = Cs octanol / Cs water = 23.9 / 7700 = 0.0031,

log Pow = -2.51

Conclusions:

The partition coefficent n-octanol/water of the test item at 20 °C, from the individual solubility in water and n-octanol, was determined to be -2.51 (log Pow).

Executive summary:

The partition coefficient n-octanol/water of FAT 21030/E at 20 °C was determined using shake flask method as described in OECD Guideline 107. According to the shake flask method, the solubility of FAT 21030/E in n-octanol is 23.9 mg/l. The water solubility of FAT 21030/E was determined to be 7700 mg/l. Hence, the partition coefficient (log Pow) was calculated to be -2.51.

Description of key information

The partition coefficient n-octanol/water of FAT 21030/E at 20 °C was determined using shake flask method as described in OECD Guideline 107. According to the shake flask method, the solubility of FAT 21030/E in n-octanol is 23.9 mg/l. The water solubility of FAT 21030/E was determined to be 7700 mg/l. Hence, the partition coefficient (log Pow) was calculated to be -2.51.

Key value for chemical safety assessment

Log Kow (Log Pow):

-2.51

at the temperature of:

20 °C