Reaction mass of dipentene and (Z)-3,7-dimethylocta-1,3,6,-triene

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:

2018-07-06 to 2018-07-07

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

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:

OECD Guidelines for the Testing of Chemicals; Guide 121 Estimation of the Adsorption Coefficient (KOC ) on Soil and on Sewage Sludge using High Performance Liquid Chromatography (HPLC)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC estimation method

Media:

other: cyanopropyl stationary phase

Specific details on test material used for the study:

Test Item Name: Ocimene PQ
Laboratory Master Schedule No. at FumoPrep Ltd.: 4417
Chemical Name: Reaction mass of (Z)-3,7-dimethylocta-1,3,6,-triene and dipentene
Batch/Lot Number: A170524D
CAS Number: 3338-55-4/138-86-3
Appearance: Colorless liquid
Expiry Date: 06 June 2019
Purity: 100%

Radiolabelling:

no

Test temperature:

55 ºC

Details on study design: HPLC method:

The determination is based on the measurement of the retention time of the test item on cyanopropyl stationary phase with methanol:water eluent.

Apparatus
Instrument Type
HPLC-UV instrument Dionex Ultimate 3000 UHPLC
Balance Sartorius-CPA225D
Ultrasonic bath Sonis 10
Micropipette 20 – 200 µL Eppendorf Research
Micropipette 100 – 1000 µL Eppendorf Research

Solutions/mixtures
Blank: The Diluent was injected as blank sample.

Diluent: HPLC water and methanol was mixed in 45:55 (V/V) ratio.

t0 Solution: Approx. 100 mg Urea was weighted with 0.01 mg precision into 10 mL volumetric flask and filled up with Diluent. The solution was mixed well by hand. The concentrations of the urea was approx. 10 mg/mL.

Stock Solution of Reference Standards: Individual stock solutions were prepared from the selected reference standards. Approx. 10 mg reference compounds were weighted with 0.01 mg precision into 10 mL
volumetric flask and filled up with Diluent. The solution was mixed well by hand. The concentrations of the reference substances were approx. 1 mg/mL (cStock).

Reference Solutions: Reference Solutions (one reference standard per solution) was prepared from the Stock Solutions of Reference Standards to identify the compounds in the Reference Mixture. Calculated volume from the stock solutions (VStock) was pipetted into 10 mL volumetric flask (VMix) and filled up to volume with Diluent (cRefSt.).

Reference Mixture-1 and Reference Mixture-2 (containing five reference standards in one solution) were prepared from the Stock Solutions of Reference Standards. Calculated volume from the stock solutions (VStock) was pipetted into 10 mL volumetric flask (VMix) and filled up to volume with Diluent. The concentrations of the reference standards in the Reference Mixture called cRefSt. in the tables below.

Stock Solution of Test Item: Approx. 10 mg test item was accurately weighted by analytical balance into 10 mL volumetric flask and filled up with Diluent and mixed well by hand.

Test Item Solution: 100 µL Stock Solution of Test Item was pipetted into 10 mL volumetric flask, filled up to volume with Diluent and mixed well by hand.

Determination of dead-time: Urea was injected for the determination of dead-time.

Calibration: The reference compounds in the Reference Mixture-1 and Reference Mixture-2 were identified based on the retention times measured in the Reference Solutions. The known log Koc values were figured as a function of calculated log k and linear calibration curve was fitted.

The log Koc of the test item was determined using this calibration curve.

Key result

Type:

log Koc

Value:

3.38 dimensionless

Details on results (HPLC method):

Urea was injected for the determination of dead-time. The reference compounds in the Reference Mixture-1 and Reference Mixture-2 were identified based on the retention times measured in the Reference Solutions. The known logKOC values were figured as a function of calculated log k and linear calibration curve was fitted. The test item was detected in 1.68 min retention time. The logKOC of the Ocimene PQ is estimated to be 3.38.

Retention times of the Urea

Component	tR (min)
Urea	0.917
	0.917
	0.917
Average	0.917

Retention times (UV) of the reference compounds

Component	logKOC	tR-UV (min)	k	log k
Acetanilide	1.25	1.070	0.167	-0.778
		1.070	0.167	-0.778
		1.070	0.167	-0.778
Phenol	1.32	1.093	0.192	-0.717
		1.090	0.189	-0.724
		1.090	0.189	-0.724
3,5-Dinitrobenzamide	2.31	1.213	0.323	-0.491
		1.213	0.323	-0.491
		1.210	0.320	-0.496
Naphthalene	2.75	1.483	0.617	-0.210
		1.480	0.614	-0.212
		1.480	0.614	-0.212
1,2,3-trichlorobenzene	3.16	1.667	0.818	-0.087
		1.663	0.814	-0.090
		1.663	0.814	-0.090
Pyrazophos	3.65	1.843	1.010	0.004
		1.843	1.010	0.004
		1.840	1.007	0.003
Phenanthrene	4.09	2.020	1.203	0.080
		2.020	1.203	0.080
		2.017	1.200	0.079

Summary of regression analysis

Summary Table
Regression Statistics
r value	0.9872
r square	0.9745
Corrected r square	0.9732
Standard Error	0.1700
Observations	21
ANOVA
	df	SS	MS	F	F significance
Regression	1	21.015	21.015	727.23	1.3116E-16
Resuidual	19	0.54906	0.02890
Sum	20	21.56
	Coefficient	SE	t value	p value	Lower 95%	Upper 95%
Intercept	3.6241	0.0519	69.8947	2.215E-24	3.516	3.733
logk	3.0966	0.1148	26.9672	1.312E-16	2.856	3.337

Component	tR (min)	k	logk	logKOC	logKOC-Mean
Ocimene PQ	1.683	0.835	-0.0781	3.38	3.38
	1.683	0.835	-0.0781	3.38
	1.683	0.835	-0.0781	3.38

Validity criteria fulfilled:

yes

Conclusions:

The logKOC of the Ocimene PQ is estimated to be 3.38.

Executive summary:

The log Koc of Ocimene PQ was determined using HPLC according to OECD TG 121. The Log Koc was determined to be 3.38.

Description of key information

The log Koc of Ocimene PQ was determined using HPLC according to OECD TG 121. The Log Koc was determined to be 3.38.

Key value for chemical safety assessment

Koc at 20 °C:

2 398