3,7-dimethyloct-6-enyl isobutyrate

Adsorption / desorption

Link to relevant study record(s)

Reference

Endpoint:

adsorption / desorption: screening

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 121 (Estimation of the Adsorption Coefficient (Koc) on Soil and on Sewage Sludge using High Performance Liquid Chromatography (HPLC))

Principles of method if other than guideline:

To determine Adsorption coefficient (KOC) on soil and on sewage sludge of the test chemical using HPLC.

GLP compliance:

no

Type of method:

HPLC estimation method

Media:

soil/sewage sludge

Radiolabelling:

not specified

Test temperature:

25°C

Details on study design: HPLC method:

The solutions of the test substance and reference substances were prepared in appropriate solvents. Each of the reference substance and test substance were analysed by HPLC at 210 nm.
After equilibration of the HPLC system, Urea was injected first, the reference substances were injected in duplicate, followed by the test chemical solution in duplicate. Reference substances were injected again after test sample, no change in retention time of reference substances was observed. Retention time tR were measured, averaged and the decimal logarithms of the capacity factors k were calculated. The graph was plotted between log Koc versus log k(Annex - 2).The linear regression parameter of the relationship log Koc vs log k were also calculated from the data obtained with calibration samples and therewith, log Koc of the test substance was determined from its measured capacity factor.

Operating Conditions:
- HPLC Model No. : Agilent Technologies,1260 Infinity
- Flow Rate : 1.0ml/min
- Column : ZORBAX Eclipse Plus C18, 4.6×100mm, 3.5 μm
- Mobile phase : Acetonitrile: water (55:45)
- Temperature : 25°C
- Detector : Diode Array Detector @210nm
- Injector : Autosampler
- Injector volume : 10μl
- Data Acquisition software : ChemStationOpen lab Control Panel

Details on sampling:

- Concentrations: 350 mg/l
- Sampling interval: A test item solution was prepared by accurately measuring 4 μL of test item and diluted with acetonitrile up to 10 ml. Thus, the test solution concentration was 350 mg/l. The pH of test substance was 6.15.

Key result

Type:

log Koc

Value:

2.272 dimensionless

pH:

6.15

Temp.:

25 °C

Remarks on result:

other: Log Koc value reported as 2.2724 ± 0.0003

Details on results (HPLC method):

The Adsorption coefficient (KOC) on soil and on sewage sludge of the 3,7-dimethyloct-6-enyl isobutyrate (CAS No. 97-89-2) was determined to be 2.2724 ± 0.0003 at 25°C.

Transformation products:

not specified

Reference substance	LogKoc	tR1	tR2	tR3	MeantR ± S.D.	k	Log k
Urea	NA	0.887	0.887	0.888	0.887 ± 0.0005	0	0
4-chloroaniline	1.96	2.012	2.021	NA	2.0165 ± 0.0063	1.2734	0.105
4-methylaniline(p- Tolouidine)	1.9	1.755	1.748	NA	1.7515 ± 0.0049	0.9746	-0.0112
N-methylaniline	2.28	2.303	2.294	NA	2.2985 ± 0.0063	1.5913	0.2018
p-toluamide	1.78	1.180	1.182	NA	1.181 0.0014	0.3315	-0.4796
Aniline	2.07	1.513	1.495	NA	1.504 ± 0.0127	0.6956	-0.1576
2,5-Dichloroaniline	2.58	3.548	3.574	NA	3.561 ± 0.0183	3.0147	0.4792
4-nitrophenol	2.46	1.559	1.56	NA	1.5595 ± 0.0007	0.7582	-0.1202
2 - nitrophenol	2.47	2.213	2.224	NA	2.2185 ± 0.0077	1.5011	0.1764
2-nitrobenzamide	1.45	1.091	1.094	NA	1.0925 ± 0.0021	0.2317	-0.6351
3-nitrobenzamide	1.95	1.159	1.158	NA	1.1585 ± 0.0007	0.3061	-0.5142
Nitrobenzene	2.35	2.426	2.429	NA	2.4275 ± 0.0021	1.7368	0.2397
4-Nitrobenzamide	1.93	1.161	1.159	NA	1.16 ± 0.0014	0.3078	-0.5118
1-naphthylamine	3.51	2.389	2.393	NA	2.391 ± 0.0028	1.6956	0.2293
1-naphtol	3.3	2.41	2.403	NA	2.4065 ± 0.0049	1.7131	0.2338
Direct Red 81	3.43	0.827	0.818	NA	0.8225 ± 0.0063	-0.0727	1.139
Benzoic acid methylester	1.8	2.585	2.61	NA	2.5975 ± 0.0176	0.1917	-0.7175
Carbendazim	2.35	1.193	1.193	NA	1.193 ± 0	0.345	-0.4622
Benzoic acid phenylester	2.87	6.57	6.642	NA	2.5975 ± 0.0509	1.9284	0.2852
Xylene	2.58	6.241	6.232	NA	6.2365 ± 0.0063	6.031	0.7804
Ethylbenzene	2.649	6.359	6.355	NA	6.357 ± 0.0028	6.1669	0.7901
Toluene	2.369	4.378	4.382	NA	4.38 ± 0.0028	3.938	0.5953
Naphthalene	2.75	6.127	6.218	NA	6.1725 ± 0.0643	5.9589	0.7752
1,2,3-trichlorobenzene	3.16	9.519	9.541	NA	9.53 ± 0.0155	9.7441	0.9887
Pentachlorophenol	3.695	8.282	8.259	NA	8.2705 ± 0.0162	8.3241	0.9203
Phenol	1.32	1.455	1.455	NA	1.455 ± 0	0.6404	-0.1936
N,N-dimethylbenzamide	1.52	1.287	1.288	NA	1.2875 ± 0.0007	0.4515	-0.3453
3,5-dinitrobenzamide	2.31	1.308	1.311	NA	1.3095 ± 0.0021	0.4763	-0.3221
N-methylbenzamide	1.3	1.175	1.174	NA	1.1745 ± 0.0007	0.3241	-0.4893
Benzamide	1.26	1.092	1.092	NA	1.092 ± 0	0.2311	-0.6362
phenantrene;phenanthrene	4.09	11.996	11.779	NA	11.8875 ± 0.1534	12.4019	1.0935
Acetanilide	1.25	1.265	1.267	NA	1.266 ± 0.0014	0.4273	-0.3693

Test substance		K	LogK	Log Koc by Generalized Calibration Graph	Mean of Log Koc ± S.D.
tR1	1.84	1.0744	0.0312	2.2722	2.2724 ± 0.0003
tR2	1.841	1.0755	0.0316	2.2727

Validity criteria fulfilled:

yes

Conclusions:

The Adsorption Coefficient of test substance was determined as per the HPLC method (OECD Guideline-121). The Log Koc value was determined to be 2.2724 ± 0.0003 at 25°C.

Executive summary:

The adsorption coefficient Koc in soil and in sewage sludge of test chemical was determined by the Reverse Phase High Performance Liquid Chromatographic method according to OECD Guideline No. 121 for testing of Chemicals.The solutions of the test substance and reference substances were prepared in appropriate solvents. A test item solution was prepared by accurately measuring 4 μL of test item and diluted with acetonitrile up to 10 ml. Thus, the test solution concentration was 350 mg/l. The pH of test substance was 6.15. Each of the reference substance and test substance were analysed by HPLC at 210 nm. After equilibration of the HPLC system, Urea was injected first, the reference substances were injected in duplicate, followed by the test chemical solution in duplicate. Reference substances were injected again after test sample, no change in retention time of reference substances was observed. Retention time tR were measured, averaged and the decimal logarithms of the capacity factors k were calculated. The graph was plotted between log Koc versus log k(Annex - 2).The linear regression parameter of the relationship log Koc vs log k were also calculated from the data obtained with calibration samples and therewith, log Koc of the test substance was determined from its measured capacity factor. The reference substances were chosen according to estimated Koc range of the test substance and generalized calibration graph was prepared. The reference substances were having Koc value ranging from 1.25 to 4.09. The Log Koc value was found to be 2.2724 ± 0.0003at 25°C. This log Koc value indicates that the test substance has a low sorption to soil and sediment and therefore have moderate migration potential to ground water.

Description of key information

The adsorption coefficient Koc in soil and in sewage sludge of test chemical was determined by the Reverse Phase High Performance Liquid Chromatographic method according to OECD Guideline No. 121 for testing of Chemicals.The solutions of the test substance and reference substances were prepared in appropriate solvents. A test item solution was prepared by accurately measuring 4 μL of test item and diluted with acetonitrile up to 10 ml. Thus, the test solution concentration was 350 mg/l. The pH of test substance was 6.15. Each of the reference substance and test substance were analysed by HPLC at 210 nm. After equilibration of the HPLC system, Urea was injected first, the reference substances were injected in duplicate, followed by the test chemical solution in duplicate. Reference substances were injected again after test sample, no change in retention time of reference substances was observed. Retention time tR were measured, averaged and the decimal logarithms of the capacity factors k were calculated. The graph was plotted between log Koc versus log k(Annex - 2).The linear regression parameter of the relationship log Koc vs log k were also calculated from the data obtained with calibration samples and therewith, log Koc of the test substance was determined from its measured capacity factor. The reference substances were chosen according to estimated Koc range of the test substance and generalized calibration graph was prepared. The reference substances were having Koc value ranging from 1.25 to 4.09. The Log Koc value was found to be 2.2724 ± 0.0003at 25°C. This log Koc value indicates that the test substance has a low sorption to soil and sediment and therefore have moderate migration potential to ground water.

Key value for chemical safety assessment

Koc at 20 °C:

187.24

Additional information

The adsorption coefficient Koc in soil and in sewage sludge of test chemical was determined by the Reverse Phase High Performance Liquid Chromatographic method according to OECD Guideline No. 121 for testing of Chemicals.The solutions of the test substance and reference substances were prepared in appropriate solvents. A test item solution was prepared by accurately measuring 4 μL of test item and diluted with acetonitrile up to 10 ml. Thus, the test solution concentration was 350 mg/l. The pH of test substance was 6.15. Each of the reference substance and test substance were analysed by HPLC at 210 nm. After equilibration of the HPLC system, Urea was injected first, the reference substances were injected in duplicate, followed by the test chemical solution in duplicate. Reference substances were injected again after test sample, no change in retention time of reference substances was observed. Retention time tR were measured, averaged and the decimal logarithms of the capacity factors k were calculated. The graph was plotted between log Koc versus log k(Annex - 2).The linear regression parameter of the relationship log Koc vs log k were also calculated from the data obtained with calibration samples and therewith, log Koc of the test substance was determined from its measured capacity factor. The reference substances were chosen according to estimated Koc range of the test substance and generalized calibration graph was prepared. The reference substances were having Koc value ranging from 1.25 to 4.09. The Log Koc value was found to be 2.2724 ± 0.0003at 25°C. This log Koc value indicates that the test substance has a low sorption to soil and sediment and therefore have moderate migration potential to ground water.

[LogKoc: 2.2724]