7-anilino-4-hydroxy-3-[[6-methoxy-4-[(6-sulpho-2,4-xylyl)azo]-m-tolyl]azo]naphthalene-2-sulphonic acid, sodium salt, compound with 2,2',2''-nitrilotriethanol

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From January 31st to February 02nd, 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

adopted July 27, 1995

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

flask method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

Type:

Pow

Partition coefficient:

0.015

Temp.:

20 °C

pH:

6

Details on results:

The partition coefficient (Pow) of test item in n-octanol - water was determined to be 0.0150 ± 0.0028 (95 % confidence interval) at 20 °C and pH ca 6.15; the related log Pow was calculated to be -1.84 using the shake flask method.

Quality criteria were met as values of log Pow derived from individual measurements fell within a range of ± 0.3 log units.

Partition coefficient measured for Test Item

Ratio of solvents (n-octanol : water)	Partition coefficient		Log Pow	pH conditions
	Pow	Mean		pH	Mean
01:01	0.0193	0.0167	-1.78	6.49	6.47
	0.0157			6.46
	0.0152			6.47
01:02	0.0201	0.0177	-1.76	6.02	6.01
	0.0170			6.00
	0.0159			6.01
02:01	0.0109	0.0106	-1.98	5.96	5.96
	0.0105			5.99
	0.0103			5.94
Mean all ± 95 % confidence interval	0.0150 ± 0.0028	-	-1.84	-

Results of the determination of concentrations

Ratio of solvents (n-octanol:water)	Measured concentration of Test Item (µg/ml)		pH	Measured concentration of Test Item (µg/ml)
	In Aqueous phase	Mean		In n-octanol phase	Mean
01:01	111.56	111.22	6.49	2.144	2.141
	110.89			2.138
	113.87	113.49	6.46	1.807	1.776
	113.11			1.746
	110.39	110.74	6.47	1.711	1.681
	111.09			1.650
Mean	111.82		6.47	1.866
Measured test item µg	2795.43		-	46.652
Total nominal quantity of test item	2705.83 µg
Total quantity of test item	2842.1 µg			Recovery: 105 %
01:02	95.42*	78.76	6.02	1.568	1.582
	78.76			1.596
	80.37	79.6	6.00	1.335	1.35
	78.84			1.365
	82.88	82.9	6.01	1.302	1.322
	82.91			1.342
Mean	80.42		6.01	1.418
Measured test item µg	2682.08		-	23.61
Total nominal quantity of test item	2705.83 µg
Total quantity of test item	2705.7 µg			Recovery: 100 %
02:01	176.05	175.55	5.96	1.94	1.919
	175.04			1.898
	170.86	168.6	5.99	1.654	1.771
	166.33			1.888
	182.19	179.79	5.94	1.832	1.856
	177.40			1.879
Mean	174.65		5.96	1.849
Measured test item µg	2907.85		-	61.648
Total nominal quantity of test item	2705.83 µg
Total quantity of test item	2969.5 µg			Recovery: 110 %

Conclusions:

log Pow: -1.84 at 20 °C and pH 6

Executive summary:

The partition coefficient was determined by flask method, according to the OECD guideline 107. The maximum concentration in either phase was less than 0.01 mol/l. Three parallel tests were carried out. In the first, the calculated volume ratio was applied, in the second, this ratio was divided by two and in the third, this ratio was multiplied by two. Three replicate samples were prepared at all solvent ratios.

The test vessels were shaken by hand through 180° about their transverse axis a hundred times during five minutes. The separation of the two phases was achieved by centrifugation at 20 °C (4000 rpm).

The partition coefficient (Pow) of test item in n-octanol - water was determined to be 0.0150 ± 0.0028 (95 % confidence interval) at 20 °C and pH ca 6.15; the related log Pow was calculated to be -1.84 using the shake flask method.

Quality criteria were met as values of log Pow derived from individual measurements fell within a range of ± 0.3 log units.

Conclusion

log Pow: -1.84 at 20 °C and pH 6

Description of key information

log Pow: -1.84 at 20 °C and pH 6

Key value for chemical safety assessment

Log Kow (Log Pow):

-1.84

at the temperature of:

20 °C

Additional information

OECD 107 - flask method