Reaction products of Hydrogen amino-4-hydroxynaphthalene-2-sulfonate, Potassium substituted-5-{[2-(sulfonatooxy)ethyl]sulfonyl}benzenesulfonate and Sodium substituted-({4-[(2-chloroethyl)sulfonyl]butanoyl}amino)benzenesulfonate

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2018

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

Specific details on test material used for the study:

Identification: FAT 40875/A TE
Lot: BOP 05-17
Appearance: Dark red powder

Analytical method:

photometric method

Type:

log Pow

Partition coefficient:

< -5.88

Temp.:

20 °C

Remarks on result:

other: pH not specified

Type:

Pow

Partition coefficient:

< 0

Temp.:

20 °C

Remarks on result:

other: pH not specified

Preliminary Visual Estimation of the n-Octanol solubility:

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

Amount of test item in mg	Volume in mL	Total volume in mL	Stirring time	Appearance of mixture
8	10	10	60 min	undissolved
8	40	50	60 min	undissolved
8	50	100	60 min	undissolved

According to this preliminary test, the solubility of the test item in n-octanol is below 0.08 g/l (without correction of the purity).

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

 

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)	-	-	-	-
Dilution	-	-	-	-
n-Octanol solubility (mg/L)	<0.66	<0.66	<0.66	-

Average experiments A to C: <0.66mg/L

Concentrations of the standards for recheck

Standard	Measured concentration (mg/L)	% Recovery
Standard 2 (c = 1.65 mg/l)	1.6	97.0
Standard 3 (c = 3.3 mg/l)	3.2	97.0
Standard 5 (c = 13.2 mg/l)	13.0	98.5

The recovery range from 97.0 to 98.5 % indicates a sufficient accuracy of the analytical method.

Calculation of the partition coefficient log P_ow from the individual solubilities

By means of the flask method, the saturation concentration of the test item in n-octanol was determined to: C_s^octanol < 0.00066 g/L.

By means of the flask method, the saturation concentration of the test item in water was determined to: C_s^water = 499.9 g/L.

Conclusions:

The partition coefficient (Pow) and log Pow of FAT 40875/A TE at 20 ± 0.5°C were <0.0000013 and <-5.88, respectively.

Executive summary:

The determination of partition coefficient (n-octanol/water) of FAT 40875/A TE was conducted based on OECD TG 105 and OECD TG 107.

 

In preliminary test, the estimated log P_OW is below -2 and therefore out of the range from -2 to 4, the partition coefficient n-octanol/water has to be estimated from the individual solubilities of the test item in water and n-octanol. According to this preliminary test the solubility of the test item in n-octanol is below 0.08 g/L.

By means of the flask method, the individual solubilities of FAT 40875/A in n-octanol and water were <0.66 mg/L and 499.9 mg/L, respectively. Hence, the partition coefficient (Pow) and log Pow of test item, FAT 40875/A TE at 20 ± 0.5°C were determined to be <0.0000013 and <-5.88, respectively.

Description of key information

The log Pow FAT 40875/A TE at 20 ± 0.5 °C was <-6.69.

Key value for chemical safety assessment

Log Kow (Log Pow):

-5.88

at the temperature of:

20 °C

Additional information

The n-octanol/water partition coefficient of FAT 40875/A TE was assesed in couple studies, conducted according to OECD TG 105 and OECD TG 107.

In the study considered to be key (2018), the partition coefficient (Pow) and log Pow of FAT 40875/A TE at 20 ± 0.5°C were determined to be <0.0000013 and <-5.88, respectively.

 

In the supporting study (2020), the partition coefficient (Pow) and log Pow of FAT 40875/A TE at 20 ± 0.5°C were determined to be <0.00000020 and <-6.69, respectively.