Cinnamaldehyde

Adsorption / desorption

Link to relevant study record(s)

Reference

Endpoint:

adsorption / desorption: screening

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

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:

no

Type of method:

HPLC estimation method

Media:

soil/sewage sludge

Radiolabelling:

no

Test temperature:

25°C

Details on study design: HPLC method:

HPLC Procedure:
The solutions of the test substance and reference substances were prepared in solvent. 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(table 3).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 : ACN : water (55:45)
Temperature : 25°C
Detector : Diode Array Detector @210nm
Injector : Autosampler
Injector volume : 10μl
Data Acquisition software : ChemStationOpen lab Control Panel

Analytical monitoring:

not specified

Key result

Sample No.:

#1

Type:

log Koc

Value:

1.958 dimensionless

pH:

6.24

Temp.:

25 °C

Remarks on result:

other: logKoc was reported to be be 1.958 ± 0.003.

Details on results (HPLC method):

The Adsorption coefficient (KOC) on soil and on sewage sludge of the test chemical was determined to be 1.958 ± 0.003 dimensionless at 25°C

Transformation products:

not specified

Tables 1

Reference substance	Log Koc	tR1	tR2	tR3	MeantR± S.D.	k	Log k
Urea	-	0.887	0.887	0.888	0.887±0.001	-	-
Benzamide	1.0	1.092	1.092		1.092±0.00	0.231	-0.636
Toluene	2.369	4.378	4.382	-	4.38±0.003	3.937	0.595
Xylene	2.58	6.241	6.232	-	6.236±0.006	6.031	0.78
Ethylbenzene	2.649	6.359	6.355	-	6.357±0.003	6.166	0.79
Naphthalene	2.75	6.127	6.218	-	6.172±0.064	5.958	0.775
Phenanthrene	4.09	11.996	11.779	-	11.887±0.153	12.401	1.09
DDT	5.63	61.125	59.008	-	60.066±1.497	66.718	1.824

Table 2

Test substance Cinnamaldehyde		K	Log k	Log Koc by Calibration Graph	Mean of LogKoc± S.D.
tR1	2.248	1.534	0.186	1.961	1.958± 0.003
tR2	2.24	1.525	0.183	1.956

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 1.958 ± 0.003 dimensionless at 25°C. Thus based on the result it is concluded that the test substance has a low sorption to soil and sediment and therefore have moderate migration potential to ground water.

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 chemical solution was prepared by accurately weighing 50mg of test chemical and diluted with mobile phase up to 100ml. Thus, the test solution concentration was 500mg/l. The pH of test substance was 6.24. 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. 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 Log Koc value of test chemical was determined to be 1.958± 0.003 dimensionless at 25°C.This log Koc value indicates that the 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 (Experimental study report, 2016). The solutions of the test substance and reference substances were prepared in appropriate solvents.A test chemical solution was prepared by accurately weighing 50mg of test chemical and diluted with mobile phase up to 100ml. Thus, the test solution concentration was 500mg/l. The pH of test substance was 6.24. 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. 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 Log Koc value of test chemical was determined to be 1.958± 0.003 dimensionless at 25°C.This log Koc value indicates that the 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:

90.78

Additional information

Experimental studies of the target chemical were reviewed for the adsorption end point which are summarized as below:

 

In an experimental study from authoritative database (2016), 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 chemical solution was prepared by accurately weighing 50mg of test chemical and diluted with mobile phase up to 100ml. Thus, the test solution concentration was 500mg/l. The pH of test substance was 6.24. 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. 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 Log Koc value of test chemical was determined to be 1.958± 0.003 dimensionless at 25°C.

 

In a supporting study, the Koc value for chemical was estimated by using a using a log Kow of 1.9 and a regression-derived equation. The estimated Koc value was 37 dimensionless (log Koc = 1.568).

 

On the basis of above overall results, it can be concluded that the log Koc value of test chemical was evaluated to be ranges from 1.56 to 1.95, respectively, indicating that the test chemicalhas a low sorption to soil and sediment and therefore have moderate migration potential to ground water.

 

Adsorption endpoint can also be considered for waiver as per in accordance with column 2 of Annex VIII of the REACH regulation,testing for this endpoint is scientifically not necessary and does not need to be conducted since the test chemical has a low octanol water partition coefficient and the adsorption potential of this substance is related to this parameter.