Decanoic acid, mixed esters with heptanoic acid, isovaleric acid, octanoic acid and pentaerythritol

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

06. Jun. 2018 to 07. Jun. 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

OECD Guidelines for the Testing of Chemicals, Method No. 117, adopted 13. April 2004: “Partition Coefficient (n-octanol/water), High Performance Liquid Chromatography (HPLC) Method“.

Deviations:

yes

Remarks:

See "Any other information" for details

Qualifier:

equivalent or similar to guideline

Guideline:

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

Version / remarks:

Commission Regulation (EU) 2016/266 adopted 7 December 2015 amending Regulation EC No. 440/2008, Method A.24 “Partition Coefficient (N-OCTANOL/WATER), HIGH PERFORMANCE LIQUID CHROMATOGRAPHY (HPLC) METHOD

Deviations:

yes

Remarks:

See "Any other information" fro details

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Specific details on test material used for the study:

No further details specified in the study report.

Analytical method:

high-performance liquid chromatography

Key result

Type:

log Pow

Partition coefficient:

> 6.5

Temp.:

25 °C

Remarks on result:

other: pH not specified

Details on results:

Result
As peaks 10 and 11 showed a relative area < 5 %, they were considered as minor peaks.
The test substance peaks showed retention times between 45.07 and 48.98 minutes. The calculation of the log POW of all peaks of the test item is not possible, because the peaks eluted outside the isocratic part of the HPLC program (40 min.). Extrapolation is therefore not possible.
In conclusion, the test item consists of components that have a log POW far outside the range of the reference item with the highest log Pow (6.5). Therefore, the log POW of the test item is stated as a > 6.5

DISCUSSION
Variations in the retention times of reference items and test item are very small. Therefore, a stable configuration of the HPLC-column can be assumed.
The correlation log k/log POW is good: the coefficient of determination r2 was calculated with 0.9926. This value was considered as sufficiently high to use the calibration function for the determination of the log POW of the test item Hatcol 1570.
The test item peaks showed retention times between 45.07 and 48.98 minutes. All peaks eluted after the reference item with highest log Pow, DDT (log POW = 6.5). The determination was precise with very low relative standard deviations of < 0.2 %. The calculation of the log POW of the test substance.is not possible, because the peaks eluted outside the isocratic part of the HPLC program (40 min.). Extrapolation is therefore not possible.
In conclusion, the test item consists of components that have a log POW far outside the range of the reference item with the highest log Pow (6.5). Therefore, the log POW of the test item is stated as a > 6.5.
No observations were made which might cause doubts concerning the validity of the study outcome.

Reference Items

Measurement Data

Retention Time (RT) of Reference Items and dead time marker

Compound	RT 1	RT 2	RT 3	RT 4	RT 5	RT 6
	Min.	Min.	Min.	Min.	Min.	Min.
Thiourea	1.436	1.436	1.437	1.437	1.437	1.437
Acetophenone	2.190	2.190	2.190	2.193	2.193	2.193
Naphthalene	5.150	5.140	5.146	5.150	5.153	5.153
Diphenyl ether	6.811	6.800	6.801	6.816	6.818	6.812
Phenanthrene	9.667	9.647	9.650	9.671	9.671	9.660
Fluoranthene	13.378	13.352	13.359	13.386	13.386	13.369
Triphenylamine	23.192	23.171	23.166	23.249	23.240	23.205
4,4’-DDT	31.826	31.806	31.792	31.934	31.913	31.867

 

Calculated Values

Capacity factors of the Reference items and dead time marker

Compound	Retention Time Mean	Retention Time Standard Deviation	Retention Time Relative Standard Deviation	k
	Min.	Min.	%
Thiourea	1.437	0.000	0.019	0.0000
Acetophenone	2.192	0.002	0.078	0.5257
Naphthalene	5.149	0.005	0.096	2.5842
Diphenyl ether	6.809	0.007	0.109	3.7403
Phenanthrene	9.661	0.011	0.109	5.7252
Fluoranthene	13.372	0.014	0.106	8.3084
Triphenylamine	23.204	0.035	0.149	15.1529
4,4’-DDT	31.856	0.058	0.183	21.1762

 

Log Pow / log k

Log k and log Pow of Reference Items

Compound	Log k	Log Pow
Acetophenone	-0.2793	1.70
Naphthalene	0.4123	3.60
Diphenyl ether	0.5729	4.20
Phenanthrene	0.7578	4.50
Fluoranthene	0.9195	5.10
Triphenylamine	1.1805	5.70
4,4’-DDT	1.3258	6.50

 

Test Item Hatcol 1570

Measurement Data

Retention Time (RT), Test Item

Measurement	RT 1	RT 2	RT 3	RT 4	RT 5	RT 6
	Min.	Min.	Min.	Min.	Min.	Min.
Measurement 1	45.068	45.376	45.646	45.940	46.227	46.581
Measurement 2	45.063	45.370	45.637	45.932	46.219	46.573
Measurement 3	45.067	45.375	45.643	45.936	46.223	46.573
Mean	45.066	45.374	45.642	45.936	46.233	46.575
Standard Deviation	0.003	0.003	0.004	0.004	0.004	0.005
Measurement	RT 7	RT 8	RT 9	RT 10	RT 11
	Min.	Min.	Min.	Min.	Min.
Measurement 1	46.966	47.367	47.855	48.382	48.983
Measurement 2	46.956	47.358	47.844	48.368	48.975
Measurement 3	46.959	47.364	47.852	48.377	48.984
Mean	46.960	47.363	47.850	48.376	48.980
Standard Deviation	0.005	0.005	0.006	0.007	0.005

 

Peak Areas, Test Item

Measurement	Area Peak 1	Relative Area Peak 1	Area Peak 2	Relative Area Peak 2
	mAU*min	%	mAU*min	%
Measurement 1	2.0509	9.53	1.5906	7.39
Measurement 2	1.7168	8.14	1.6274	7.72
Measurement 3	1.8883	9.26	1.5800	7.75
Mean	1.8853	8.98	1.5993	7.62
Relative Standard Deviation	8.86%	8.17%	1.56%	2.64%
Measurement	Area Peak 3	Relative Area Peak 3	Area Peak 4	Relative Area Peak 4
	mAU*min	%	mAU*min	%
Measurement 1	2.3539	10.93	2.9562	13.73
Measurement 2	2.4721	11.73	3.1346	14.87
Measurement 3	2.3483	11.52	2.9500	14.47
Mean	2.3914	11.39	3.0136	14.36
Relative Standard Deviation	2.92%	3.62%	3.48%	4.03%
Measurement	Area Peak 5	Relative Area Peak 5	Area Peak 6	Relative Area Peak 6
	mAU*min	%	mAU*min	%
Measurement 1	1.4337	6.66	3.2905	15.28
Measurement 2	1.4662	6.96	3.3265	15.78
Measurement 3	1.3668	6.70	3.2012	15.70
Mean	1.4222	6.77	3.2727	15.59
Relative Standard Deviation	3.56%	2.36%	1.97%	1.72%
Measurement	Area Peak 7	Relative Area Peak 7	Area Peak 8	Relative Area Peak 8
	mAU*min	%	mAU*min	%
Measurement 1	2.4561	11.41	1.8864	8.76
Measurement 2	2.1305	10.1	1.6930	8.03
Measurement 3	2.0491	10.05	1.6157	7.93
Mean	2.2119	10.52	1.732	8.24
Relative Standard Deviation	9.74%	7.30%	8.05%	5.53%
Measurement	Area Peak 9	Relative Area Peak 9	Area Peak 10	Relative Area Peak 10
	mAU*min	%	mAU*min	%
Measurement 1	1.8167	8.44	0.8219	3.82
Measurement 2	1.8331	8.70	0.8347	3.96
Measurement 3	1.7624	8.64	0.8063	3.96
Mean	1.8041	8.59	0.821	3.91
Relative Standard Deviation	2.05%	1.59%	1.73%	2.07%
Measurement	Area Peak 11	Relative Area Peak 11
	mAU*min	%
Measurement 1	0.8728	4.05
Measurement 2	0.8440	4.00
Measurement 3	0.8187	4.02
Mean	0.8452	4.02
Relative Standard Deviation	3.20%	0.65%

As peaks 10 and 11, showed a relative area < 5%, they were considered as minor peaks.

 

Calculated Values

Capacity Factor, log Capacity Factor, log Pow Test Item Peaks

Peak	Measurement No.	k	Log k	Log Pow
1	1	30.3737	1.4825	6.751
	2	30.3701	1.4824	6.751
	3	30.3729	1.4825	6.751
	Mean			6.751
	Standard Deviation			0.000
2	1	30.5879	1.4855	6.760
	2	30.5839	1.4855	6.760
	3	30.5868	1.4855	6.760
	Mean			6.760
	Standard Deviation			0.000
3	1	30.7760	1.4882	6.768
	2	30.7698	1.4881	6.767
	3	30.7736	1.4882	6.767
	Mean			6.767
	Standard Deviation			0.000
4	1	30.9805	1.4911	6.776
	2	30.9751	1.4910	6.776
	3	30.9778	1.4911	6.776
	Mean			6.776
	Standard Deviation			0.000
5	1	31.1800	1.4939	6.784
	2	31.1747	1.4938	6.784
	3	31.1773	1.4938	6.784
	Mean			6.784
	Standard Deviation			0.000
6	1	31.4266	1.4973	6.794
	2	31.4208	1.4972	6.794
	3	31.4208	1.4972	6.794
	Mean			6.794
	Standard Deviation			0.000
7	1	31.6944	1.5010	6.805
	2	31.6877	1.5009	6.804
	3	31.6895	1.5009	6.804
	Mean			6.805
	Standard Deviation			0.000
8	1	31.9738	1.5048	6.816
	2	31.9673	1.5047	6.815
	3	31.9716	1.5048	6.816
	Mean			6.816
	Standard Deviation			0.000
9	1	32.3136	1.5094	6.829
	2	32.3061	1.5093	6.829
	3	32.3112	1.5094	6.829
	Mean			6.829
	Standard Deviation			0.000
10	1	32.6802	1.5143	6.843
	2	32.6710	1.5142	6.843
	3	32.6772	1.5172	6.843
	Mean			6.843
	Standard Deviation			0.000
11	1	33.0986	1.5198	6.859
	2	33.0931	1.5197	6.859
	3	33.0992	1.5198	6.859
	Mean			6.859
	Standard Deviation			0.000

Log Pow was calculated from the capacity factor as follows:

Log Pow = (log k + 0.8393) / 0.3439

Conclusions:

In conclusion, the test item consists of components that have a log POW far outside the range of the reference item with the highest log Pow (6.5). Therefore, the log POW of the test item is stated as a > 6.5

Executive summary:

Determination of the log POW of Hatcol 1570 using the HPLC method according to OECD 117 resp. EU A.24

 

Findings:

The study was performed using a HPLC with a C18 column. Seven reference items with different retention times and thiourea for the determination of the dead time were used to produce a calibration curve, since retention time on hydrophobic columns and POW are correlated. The reference items were chosen based on the results of the pre-test.

 

One vial was filled with the reference item mix and one vial with the test item solution. The vials were analysed using the HPLC with the program described below. First one injection from the solvent blank methanol was made. Then three injections were measured from the reference item mix, three injections from the test item and again three injections from the reference item mix.

 

Pre-tests with UV-detection (non-GLP) were performed using the standard eluent system methanol/water 75/25 %, but no peaks were detected in the test substance solution. Therefore, a washing step with up to 100% methanol appended after elution of the last reference item. Significant differences between blank and test substance solution were detected with the washing step. This showed that test substance peaks are detectable and are eluted from the HPLC column after DDT. DDT is the reference substance with the highest retention time.

 

For each reference substance, the capacity factor k was calculated from the retention time of thiourea and the retention time of the respective reference substance.

A calibration function (log k versus log POW, linear fit) was determined using the literature values for POW of the reference substances and the retention times in the six determinations.

 

The test item peaks showed retention times between 45.07 and 48.98 minutes. All peaks eluted after the reference substance with highest log Pow, DDT (log POW = 6.5). The determination was precise with very low relative standard deviations of < 0.2 %. The calculation of the log POW of the test substance is not possible, because the peaks eluted outside the isocratic part of the HPLC program (40 min.). Extrapolation is therefore not possible.

 

In conclusion, the test item consists of components that have a log POW far outside the range of the reference item with the highest log Pow (6.5). Therefore, the log POW of the test item is stated as > 6.5.

Description of key information

The log POW of the test item is stated as > 6.5.

Key value for chemical safety assessment

Log Kow (Log Pow):

6.5

at the temperature of:

25 °C

Additional information

The test item peaks showed retention times between 45.07 and 48.98 minutes. All peaks eluted after the reference substance with highest log Pow, DDT (log POW = 6.5). The determination was precise with very low relative standard deviations of < 0.2 %. The calculation of the log POW of the test substance is not possible, because the peaks eluted outside the isocratic part of the HPLC program (40 min.). Extrapolation is therefore not possible.

In conclusion, the test item consists of components that have a log POW far outside the range of the reference item with the highest log Pow (6.5). Therefore, the log POW of the test item is stated as > 6.5.