Reaction mass of Disodium [3-{[4-chloro-2-(hydroxy-kO)-5-methoxyphenyl]diazenyl-kN2}-4-(hydroxy-kO)naphthalene-2,7-disulfonato(4-)](hydroxy)chromate(2-) and Trisodium [3-{[4-chloro-2-(hydroxy-kO)-5-methoxyphenyl]diazenyl-kN2}-4-(hydroxy-kO)naphthalene-2,7-disulfonato(4-)](dihydroxy)chromate(3-)

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

07 July 2020 to 28 July 2020

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

GLP compliance:

no

Type of method:

flask method

Partition coefficient type:

octanol-water

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch number of test material: SI/May2020/CR/001(India)

Analytical method:

other: UV-VIS PerkinElmer Lambda 25- Spectrophotometry

Type:

Pow

Partition coefficient:

0

Temp.:

20 °C

Remarks on result:

other: pH not specified

Individual Results

Preliminary Visual Estimation of the n-Octanol solubility

5 mg of the test item were stirred with different amounts of n-octanol at room temperature and visually checked for any undissolved particles.

 

Appearance of the test mixtures:

Amount of test item in mg	Added volume in ml	Total volume in ml	Stirring time	Appearance of mixture
5	100	100	60 min	undissolved
	100	200	60 min	undissolved
	50	250	60 min	undissolved

 

According to this preliminary test the solubility of the test item in n-octanol is below 0.02 g/l (without correction for the purity).

 

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 from the experiments (cs^octanol <0.02 g/l) and the preliminary test (cs^water= 515.74 g/l), the partition coefficient was calculated. Due to the fact that the estimated log Pow may be below -4, which may beyond the applicable range between -2 and 4 of OECD TG 107, the partition coefficient n-octanol/water is estimated from the individual solubilities in water and n-octanol.

 

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

Solubility of the test item – experiments A to D

Experiment	A	B	C	D (Blank)
Amount of test item (mg)	500	500	500	--
Stirring time at 30 °C (h)	24	48	72	72
Measured concentration (mg/l)	0.25	0.10	0.28	--
Dilution	-	-	-	--
n-Octanol solubility (mg/l)	0.25	0.10	0.28	--

 

Average experiments A to C: 0.21 mg/l

 

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: cs^octanol= 0.00021 g/l.

By means of the flask method, the saturation concentration of the test item in water was determined to: cs^water= 515.74 g/l.

Conclusions:

The partition coefficient n-octanol/water of the test item at 20 °C, calculated from the individual solubility in water and n-octanol was Pow = 0.0000004 and log Pow = -6.39.

Executive summary:

Partition coefficient n-octanol / water (Individual solubility in water and n-octanol) of FAT 20044/C was carried out according to OECD guideline 107 and EU method A.8 using flask method. According to the preliminary test the solubility of the test item in n-octanol is below 0.02 g/l (without correction for the purity). Due to the fact that the estimated log Pow may be below -4, which may beyond the applicable range between -2 and 4 of OECD TG 107, the partition coefficient n-octanol/water is estimated from the individual solubility in water and n-octanol. Based on the study results, the partition coefficient n-octanol/water of the test item at 20 °C, from the individual solubility in water and n-octanol was Pow = 0.0000004 and log Pow = -6.39, respectively.

Description of key information

The partition coefficient n-octanol/water of the test item at 20 °C, from the individual solubility in water and n-octanol, was Pow = 0.0000004 and log Pow = -6.39.

Key value for chemical safety assessment

Log Kow (Log Pow):

-6.39

at the temperature of:

20 °C

Additional information

Partition coefficient n-Octanol / Water (Individual solubilities in water and n-octanol) of FAT 20044/C was carried out according to OECD guideline 107 and EU method A.8 using flask method. According to the preliminary test, the solubility of the test item in n-octanol is below 0.02 g/l (without correction for the purity). Due to the fact that the estimated log Pow may be below -4, which may beyond the applicable range between -2 and 4 of OECD TG 107, the partition coefficient n-octanol/water is estimated from the individual solubility in water and n-octanol. Based on the study results, the partition coefficient n-octanol/water of the test item at 20 °C, from the individual solubility in water and n-octanol, was Pow = 0.0000004 and log Pow = -6.39.