1,4-bis(p-tolylamino)anthraquinone

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

comparable to guideline study

Qualifier:

according to guideline

Guideline:

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

Qualifier:

according to guideline

Guideline:

EU Method A.8 (Partition Coefficient - HPLC Method)

Principles of method if other than guideline:

The octanol water partition coefficient of test chemical was determined by using HPLC method in accordance with OECD Guideline 117 (Partition Coefficient (n-octanol / water), HPLC Method) and EU Method A.8 (Partition Coefficient - HPLC Method), respectively.

GLP compliance:

yes

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

Key result

Type:

log Pow

Partition coefficient:

8.16

Temp.:

40 °C

Remarks on result:

other: other details not available

Table 1: Determined values of the calibration substances (single values).

 

Calibration items	Retention time [tr] (min) Test 1	Retention time [tr] (min) Test 2	Retention time [tr] (min) Test 3	Standard deviation of the retention time [tr] (min)	Relative standard deviation %
Thiourea (dead time (to))	1.345	1.344	1.344	0.001	0.043
2,3-Dichloroaniline	2.117	2.116	2.116	0.001	0.027
Biphenyl	2.733	2.731	2.731	0.001	0.042
Phenanthrene	3.261	3.260	3.259	0.001	0.031
Triphenylamine	4.179	4.178	4.176	0.002	0.037
Bis(2-ethylhexyl)phthalate	11.314	11.308	11.299	0.008	0.067
Decachlorobiphenyl	20.601	20.584	20.607	0.012	0.058

 

 

 

Table 2: Mean value of 3 single values of the calibration substances.

 

Calibration items	Retention time [tr] = min	Capacity factor k’	Log k’	Log Pow
Thiourea (dead time (fa))	1.344	----	—	—
2,3-Dichloroaniline	2.116	0.574	- 0.241	2.8
Biphenyl	2.732	1.032	0.014	4.0
Phenanthrene	3.260	1.425	0.154	4.5
Triphenylamine	4.178	2.108	0.324	5.7
Bis(2-ethylhexyl)phthalate	11.307	7.411	0.870	7.5
Decachlorobiphenyl	20.597	14.322	1.156	8.3

 

 

Table 3: Determined values of the test chemical.

 

Test item	Retention time [tr] (min) Test 1	Retention time [tr] (min) Test 2	Retention time [tr] (min) Test 3	Standard deviation of the retention time [tr] (min)	Relative standard deviation of the retention time [tr] (%)
Test chemical	16.487	16.473	16.459	0.0140	0.08

 

 

 Table 4: Mean value of 3 single values of the test chemical.

 

Test item	Retention time [tr] = min	Capacity factor k’	Log k’	Log Pow
Test chemical	16.473	11.254	1.0510	8.16

 

Conclusions:

The octanol water partition coefficient of test chemical was determined to be 8.2 by using HPLC method at 40oC. On the basis of this log Pow value it is concluded that test chemical is considered to be hydrophobic in nature.

Executive summary:

The partition coefficient (Pow) of test chemical was determined according to the HPLC method at 40 °C in accordance with OECD Guideline 117 (Partition Coefficient (n-octanol / water), HPLC Method) and EU Method A.8 (Partition Coefficient - HPLC Method), respectively. According to OECD guideline 117 and considering environmental relevance, buffered water at pH 5 was chosen. The reference Pow-values in the OECD-guideline presumably refer to 25 °C. Even though the column temperature was 40 °C, this temperature is without influence on the result of the determination. The calibration was done referring to Pow- values of reference substances determined at 25 °C. For the determination of the partition coefficient (Kow) four calibration standards with log Kow from 2.8 - 5.7 are established in the EG-test method. As no calibration standard with log Pow > 5.7 is established in the EG-test method, two new reference substances (bis(2-ethylhexyl)phthalate and decachlorobiphenyl ) were used in this test. For both reference substances the log Pow -values were determined by the slow stirring method. The log Pow value determined were 7. 5 for bis(2-ethylhexyl)phthalate and 8. 3 for decachlorobiphenyl. On the basis of calibration graph, log Pow value of test chemical was determined to be 8.2 dimensionless.On the basis of this log Pow value, it is concluded that test chemical is hydrophobic in nature.

Description of key information

Based on the available data from experimental study report,the partition coefficient (Pow) of test chemical was determined according to the HPLC method at 40 °C in accordance with OECD Guideline 117 (Partition Coefficient (n-octanol / water), HPLC Method) and EU Method A.8 (Partition Coefficient - HPLC Method), respectively. According to OECD guideline 117 and considering environmental relevance, buffered water at pH 5 was chosen. The reference Pow-values in the OECD-guideline presumably refer to 25 °C. Even though the column temperature was 40 °C, this temperature is without influence on the result of the determination. The calibration was done referring to Pow- values of reference substances determined at 25 °C. For the determination of the partition coefficient (Kow) four calibration standards with log Kow from 2.8 - 5.7 are established in the EG-test method. As no calibration standard with log Pow > 5.7 is established in the EG-test method, two new reference substances (bis(2-ethylhexyl)phthalate and decachlorobiphenyl ) were used in this test. For both reference substances the log Pow -values were determined by the slow stirring method. The log Pow value determined were 7. 5 for bis(2-ethylhexyl)phthalate and 8. 3 for decachlorobiphenyl. On the basis of calibration graph, log Pow value of test chemical was determined to be 8.2 dimensionless. On the basis of this log Pow value, it is concluded that test chemical is hydrophobic in nature.

Key value for chemical safety assessment

Log Kow (Log Pow):

8.2

at the temperature of:

40 °C

Additional information

Based on the available data in a key study from experimental study report,the partition coefficient (Pow) of test chemical was determined according to the HPLC method at 40 °C in accordance with OECD Guideline 117 (Partition Coefficient (n-octanol / water), HPLC Method) and EU Method A.8 (Partition Coefficient - HPLC Method), respectively. According to OECD guideline 117 and considering environmental relevance, buffered water at pH 5 was chosen. The reference Pow-values in the OECD-guideline presumably refer to 25 °C. Even though the column temperature was 40 °C, this temperature is without influence on the result of the determination. The calibration was done referring to Pow- values of reference substances determined at 25 °C. For the determination of the partition coefficient (Kow) four calibration standards with log Kow from 2.8 - 5.7 are established in the EG-test method. As no calibration standard with log Pow > 5.7 is established in the EG-test method, two new reference substances (bis(2-ethylhexyl)phthalate and decachlorobiphenyl ) were used in this test. For both reference substances the log Pow -values were determined by the slow stirring method. The log Pow value determined were 7. 5 for bis(2-ethylhexyl)phthalate and 8. 3 for decachlorobiphenyl. On the basis of calibration graph, log Pow value of test chemical was determined to be 8.2 dimensionless.

In a supporting study from study report (2018), the partition Coefficient n-octanol/water of test chmeical was determined by the Reverse Phase High Performance Liquid Chromatographic method according to OECD Guideline No. 117 for testing of Chemicals. A test item solution was prepared by accurately weighing 4 mg of test item and diluted with Acetonitrile up to 10 ml. Thus, the test solution concentration was 400 mg/l. The pH of test substance was 6.2. The reference substances were chosen according to estimated Pow range of the test substance and generalized calibration graph was prepared. The reference substances were 4-Methoxyphenol, Benzophenone, Phenol, Benzene, Methyl benzoate, 1,4-Dichlorobenzene, Chlorobenzene, Bromobenzene, 2,3-Dichloroaniline, 2-Nitrophenol, Nitrobenzene, 2,6 -Dichlorobenzonitrile, Cinnamyl alcohol, 4-Methylbenzyl alcohol, Phenoxyacetic acid, Cinnamic Acid, Dodecanoic acid, Toluene, Ethylbenzene, n-Butylbenzene, Diphenyl ether, Allyl phenyl ether, DDT having Pow value ranging from 1.3 to 6.5. The Log Pow value of test chemical was determined to be 6.407 ± 0.000 at 25°C.

Thus, based on the available information, the logPow value of the test chemical was determined to be ranges from 6.4 to 8.2, respectively. On the basis of this experimental value, test chemical can be considered to be hydrophobic in nature.