Reaction mass of Rel-(3aR,4S,7R,7aS)-1-(methoxymethylene)octahydro-1H-4,7-methanoindene and Rel-(3aR,4S,7R,7aS)-2-(methoxymethylene)octahydro-1H-4,7-methanoindene

Adsorption / desorption

Link to relevant study record(s)

Reference

Endpoint:

adsorption / desorption: screening

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Experimental starting date: 13 December 2017 Experimental completion date: 07 March 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method C.19 (Estimation of the Adsorption Coefficient (KOC) on Soil and Sewage Sludge Using High Performance Liquid Chromatography (HPLC))

Version / remarks:

(2008)

Deviations:

no

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))

Version / remarks:

(2001)

Deviations:

no

GLP compliance:

yes

Type of method:

HPLC estimation method

Specific details on test material used for the study:

Identification: FRET 14-0383
Appearance/physical state: colorless liquid
Batch: RDGM435-97
Purity: 95.1%
Expiry date: 01 January 2019
Storage conditions: approximately 4 °C, in the dark

Radiolabelling:

no

Test temperature:

30°C

Details on study design: HPLC method:

The test system utilized a high performance liquid chromatograph and a cyanopropyl reverse phase HPLC column, containing lipophilic and polar moieties was used.

Performance of the Test
Preparation of sample solution
Test item (0.1132 g) was diluted to 100 mL with methanol. This solution was then diluted by a factor of 10 with methanol to give a concentration of 113 mg/L, prior to analysis.
Preparation of dead time solution
The dead time was determined by measuring the retention time of formamide (purity* 99.6%, 675 mg/L solution in methanol).

Determination of retention time
The sample, dead time and reference standard solutions were injected in duplicate using the following HPLC parameters:
HPLC System : Agilent Technologies 1100 Series, incorporating autosampler and workstation
Detector type : ultraviolet (UV)
Column : Zorbax Eclipse XDB-CN 5 μm (150 x 4.6 mm id)
Column temperature : 30 ºC
Mobile phase : methanol: water (55:45 v/v)
pH of mobile phase : 6.0
Flow-rate : 1.0 mL/min
Injection volume : 10 μL
UV detector wavelength : 210 nm

Calculation
The capacity factors (k') for the reference standards were calculated using:
k' = (tr-t0)/t0
where:
k'= capacity factor
tr= retention time (min)
t0= dead time (min)

A correlation of log k' versus log Koc of the calibration standards was plotted using linear regression. The adsorption coefficient was calculated using the following equation:
Log10 Koc = (Log10 k' - A)/B
where:
Koc= adsorption coefficient
k'= capacity factor
A= intercept of the calibration curve
B= slope of the calibration curve

Key result

Type:

log Koc

Value:

3.16 dimensionless

pH:

6

Temp.:

30 °C

Details on results (HPLC method):

The method guidelines state that the measurement of adsorption coefficient should be carried out on substances in their ionized and unionized forms, within the environmentally relevant pH range, where applicable. However, in the absence of any dissociating functional groups, this was not necessary for this test item and therefore only a single determination was performed, at an approximately neutral pH, on the test item in an unionized form.

Calibration

The retention times of the dead time and the retention times, capacity factors (k') and log10Koc values for the reference standards are shown in the two following tables:

Dead time	Retention time (mins)		Mean retention time (mins)
	Injection 1	Injection 2
Formamide	1.657	1.659	1.658

Standard	Retention time (mins)			Capacity factor (k')	Log10k'	Log10Koc
	Injection 1	Injection 2	Mean
Acetanilide	2.147	2.147	2.147	0.295	-0.530	1.25
Phenol	2.203	2.203	2.203	0.328	-0.484	1.32
Atrazine	2.557	2.559	2.558	0.543	-0.265	1.81
Triadimenol	3.421	3.418	3.419	1.062	2.62 x 10^-2	2.40
Linuron	4.059	4.059	4.059	1.448	0.161	2.59
Naphthalene	3.765	3.763	3.764	1.270	0.104	2.75
Endosulfan-diol	5.114	5.109	5.112	2.083	0.319	3.02
Fenthion	6.689	6.686	6.687	3.033	0.482	3.31
a-Endosulfan	8.144	8.144	8.144	3.911	0.592	4.09
Diclofop-methyl	7.858	7.853	7.855	3.737	0.573	4.20
Phenanthrene	6.579	6.577	6.578	2.967	0.472	4.09
DDT	17.637	17.632	17.635	9.635	0.984	5.63

Adsorption Coefficient

The retention times, capacity factor and log10 Koc value determined for the sample are shown in the following table:

Injection	Retention time (mins)	Capacity factor (k')	Log10k'	Log10Koc	Mean log10Koc	Adsorption coefficient
1	4.573	1.758	0.245	3.16	3.16	1.45 x 10^3
2	4.571	1.756	0.245	3.16

Validity criteria fulfilled:

yes

Conclusions:

The adsorption coefficient (Koc) of the test item has been determined to be 1450, log10Koc 3.16.

Executive summary:

The HPLC screening method was applied for the determination of the adsorption coefficient (Koc) of FRET 14 -0383.The mobile phase was 55/45 (v/v) methanol/water. The column temperature was 30°C. The log Koc value of the test substance was 3.16 (Koc = 1450).The study was performed in accordance with EC C.19 and OECD 121 and according to the principles of GLP.

Description of key information

The HPLC screening method was applied for the determination of the adsorption coefficient (Koc) of FRET 14 -0383.The mobile phase was 55/45 (v/v) methanol/water. The column temperature was 30°C. The log Koc value of the test substance was 3.16 (Koc = 1450).The study was performed in accordance with EC C.19 and OECD 121 and according to the principles of GLP.

Key value for chemical safety assessment

Koc at 20 °C:

3.16