Methyl 2-naphthyl ether

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

Justification for type of information:

Experimental test result performed using standard test guidelines

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Type of method:

HPLC estimation method

Media:

soil/sewage sludge

Radiolabelling:

no

Test temperature:

30.0 °C

Details on study design: HPLC method:

HPLC Procedure
The solutions of the test substance and reference substances were prepared in solvent. After column saturation with the mobile phase, sequential analysis of thiourea (for dead time: t0), reference substances and test chemical were performed on HPLC at 254 nm. The solutions of the test substance and reference substances were prepared in solvent. In HPLC system, thiourea was injected first, the reference substances were injected, followed by the test chemical solution. All the HPLC runs were performed in duplicates. Retention time tR was measured to calculate the capacity factors k', it was then converted in log to obtain log k'. A standard curve between log k versus log Koc was plotted to obtain the value of log Koc of the test chemical.

EQUIPMENT
- Apparatus: HPLC equipped with Diode Array Detector
- Type, material and dimension of analytical (guard) column: CPS HYPERSIL (CN), 250 mm length x 4.6 mm inner diameter, 5μm particle size)
- Detection system: Diode Array Detector
- Wavelength: UV-254 nm
- Flow rate: 1.00 ml/min
-Injector: Autosampler
- Temperature: 30°C

MOBILE PHASES
- Experiments with additives carried out on separate columns: no
- Type: Methanol: Water, 55:45 (v/v)
- pH: since no additives added, so pH measurement not required for this mobile phase.

REFERENCE SUBSTANCES
- Identity: Acetanilide, Atrazine, Acetophenone, Naphthalene, Methyl Benzoate and Phenanthrene

DETERMINATION OF DEAD TIME
- Method: Dead time was determined by injecting about 100mg/L of thiourea solution in duplicate.

DETERMINATION OF RETENTION TIMES
- Quantity of test substance introduced in the column: 10 µl
- Quantity of reference substances: 10 µl
- Intervals of calibration: Not required

REPETITIONS
- Number of determinations: Duplicates

EVALUATION
- Calculation of capacity factors k': yes
- Calculation of retention times: yes
- Determination of the log Koc value: The adsorption coefficient (Koc) was calculated from the capacity factor (k’) using a calibration plot of log k’ versus log Koc of the selected reference items.

Analytical monitoring:

not required

Key result

Sample No.:

#1

Type:

log Koc

Value:

3.06 dimensionless

Temp.:

30 °C

Remarks on result:

other: Koc = 1148.15

Details on results (HPLC method):

- Retention times of reference substances used: Retention time of reference substance was determined to be 3.443, 3.520, 3.593, 3.61, 3.95, 4.44 for Acetanilide, Atrazine, Acetophenone, Naphthalene, Methyl Benzoate and Phenanthrene, respectively.
- Details of fitted regression line (log k' vs. log Koc): Log Koc = 3.8721(log k’) + 5.1986 with R2 = 0.977
- Graph of regression line attached: Graph has been attached with this template.
- Average retention data for test substance: 4.06 (retention time) of test chemical.


The Adsorption Coefficient of test chemical was determined as per the HPLC method (OECD Guideline-121). The Log Koc value was determined to be 3.06 dimensionless (Koc = 1148.15) at 30°C.
The Log Koc was calculated for the test item from the capacity factor (k’) using a calibration plot of log k’ versus log Koc of the selected six known reference items.
Regression equation for the compounds analysed was:
Log Koc = 3.8721(log k’) + 5.1986 with R2 = 0.977

Transformation products:

not specified

Result: Determination of log Koc

Determination of Dead Time (t0)
Name	Replicate	RT(to)min	Average RT(to)min
Thiourea	R1	3.173	3.173
	R2	3.173
Determination of Retention Time (tR)
Name	Replicate	RT(tR)min	k'	log k'	Average	log Koc
Acetanilide	R1	3.427	0.0801	-1.0966	-1.0858	1.25
	R2	3.440	0.0841	-1.0750
Acetophenone	R1	3.520	0.1094	-0.9611	-0.9611	1.26
	R2	3.520	0.1094	-0.9611
Methyl Benzoate	R1	3.593	0.1324	-0.8782	-0.8782	1.80
	R2	3.593	0.1324	-0.8782
Atrazine	R1	3.607	0.1368	-0.8640	-0.8610	1.81
	R2	3.613	0.1387	-0.8580
Naphthalene	R1	3.960	0.2480	-0.6055	-0.6074	2.75
	R2	3.953	0.2458	-0.6094
Phenanthrene	R1	4.707	0.4835	-0.3156	-0.3148	4.09
	R2	4.713	0.4853	-0.3139
Slope =						3.8721
Intercept =						5.1986
Name	Replicate	RT(tR)min	k'	log k'	log Koc	Average
Test chemical	R1	4.067	0.2818	-0.5501	3.07	3.06
	R2	4.053	0.2773	-0.5570	3.04

Validity criteria fulfilled:

yes

Conclusions:

The Adsorption Coefficient of test chemical was determined as per the HPLC method (OECD Guideline-121). The Log Koc value was determined to be 3.06 dimensionless (Koc = 1148.15) at 30°C.

Executive summary:

The adsorption coefficient Koc in soil and in sewage sludge of test chemical was determined by the 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 methanol solvent. For the preparation of test solution 10.37 mg of the test item was weighed and transferred into a 10 mL volumetric flask, dissolved and volume was made up to the mark with methanol. 100µl of this solution was pipetted out into vial and 900µl of methanol added to it was shaken well. The concentration of the test chemical solution was 103.7mg/L.  After column saturation with the mobile phase, sequential analysis of thiourea (for dead time: t0), reference substances and test chemical were performed on HPLC at 254 nm. In HPLC system, thiourea was injected first, the reference substances were injected, followed by the test chemical solution. The 10ml volume of each was introduced in the column by using autosampler. All the HPLC runs were performed in duplicates. Retention time tR was measured to calculate the capacity factors k', it was then converted in log to obtain log k'. A standard curve between log k versus log Koc was plotted to obtain the value of log Koc of the test chemical. Reference substance taken for study includes Acetanilide, Atrazine, Methyl Benzoate, Naphthalene , Phenanthrene and Acetophenone having log Koc value ranging from 1.25 to 4.09 dimensionless. The Adsorption Coefficient of test chemical was determined as per the HPLC method (OECD Guideline-121). The Log Koc value was determined to be 3.06 dimensionless at 30°C. This log Koc value indicates that the test chemical has a moderate sorption to soil and sediment and therefore have slow 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 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 methanol solvent. For the preparation of test solution 10.37 mg of the test item was weighed and transferred into a 10 mL volumetric flask, dissolved and volume was made up to the mark with methanol. 100µl of this solution was pipetted out into vial and 900µl of methanol added to it was shaken well. The concentration of the test chemical solution was 103.7mg/L.  After column saturation with the mobile phase, sequential analysis of thiourea (for dead time: t0), reference substances and test chemical were performed on HPLC at 254 nm. In HPLC system, thiourea was injected first, the reference substances were injected, followed by the test chemical solution. The 10ml volume of each was introduced in the column by using autosampler. All the HPLC runs were performed in duplicates. Retention time tR was measured to calculate the capacity factors k', it was then converted in log to obtain log k'. A standard curve between log k versus log Koc was plotted to obtain the value of log Koc of the test chemical. Reference substance taken for study includes Acetanilide, Atrazine, Methyl Benzoate, Naphthalene , Phenanthrene and Acetophenone having log Koc value ranging from 1.25 to 4.09 dimensionless. The Adsorption Coefficient of test chemical was determined as per the HPLC method (OECD Guideline-121). The Log Koc value was determined to be 3.06 dimensionless at 30°C. This log Koc value indicates that the test chemical has a moderate sorption to soil and sediment and therefore have slow migration potential to ground water.

Key value for chemical safety assessment

Koc at 20 °C:

1 148.15