Oxacycloheptadecan-2-one

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:

26 July 2016 - 27 July 2016

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

Media:

soil

Specific details on test material used for the study:

- Appearance: Colourless to very pale yellowish oily liquid when received. Opaque crystalline mass after storage in the refrigerator.
- Storage conditions: In refrigerator (2-8°C)

Details on study design: HPLC method:

CALCULATION OF PKA
-Perrin calculation method (pKalc 5.0, module in Pallas 3.0, CompuDrug International, USA) for the logarithm range of 1 - 14.
-Result: pKa acidic: none; pKa basic: none.

HPLC CONDITIONS
- Instrument: Acquity UPLC system (Waters, USA)
- Detector: Acquity UPLC TUV (Waters, USA)
- Column: Acquity UPLC HSS Cyano, 100 mm x 2.1 mm i.d., dp=1.8 μm (Waters, USA)
- Column temperature: 35°C
- Mobile phase: 55/45 (v/v) methanol/water
- Flow: 0.4 mL/min
- Injection volume: 5 μL
- UV detection: 210 nm

UNRETAINED SUBSTANCE, REFERENCE SUBSTANCES AND TEST SUBSTANCE SOLUTIONS
- Unretained substance: formamide
- Reference substances with known log Koc values (log Koc values according to OECD 121, based on soil adsorption data).
- Solutions of the unretained substance and of the reference substances were prepared in the mobile phase (using stock solutions in methanol)
- Test substance solution: A 1000 mg/L solution of the test substance was prepared in methanol.

INJECTIONS
- Solutions of the unretained substance, the reference substances and the test substance were injected in duplicate.
- Single injection of the blank solutions (55/45 (v/v) methanol/water and methanol).

DATA HANDLING
- Dead time (t0)= mean retention time of the unretained substance
- Duplicate capacity factors (k') for each reference substance were calculated from the retention times (tr). k'= (tr-t0)/t0
- Log k’ values of the references substances were plotted against the known log Koc values.
- Linear regression analysis (least squares method) resulted in the regression line log k’ = 0.331 x log Koc - 0.820 (r=0.98, n=16)
- Capacity factor (k') of the substance was calculated from its retention time and the dead time.
- Log Koc of the substance was calculated by substituting its mean log k’ in the regression line.
- The value of log Koc obtained from duplicate measurements was within ± 0.25 log units.

Key result

Type:

Koc

Value:

380 000 L/kg

Temp.:

20 °C

Remarks on result:

other: Non-buffered mobile phase.

Type:

log Koc

Value:

5.58 dimensionless

Temp.:

20 °C

Remarks on result:

other: Non-buffered mobile phase.

Details on results (HPLC method):

The chromatogram of the 1 g/L test substance solution showed one peak, with a mean retention time of 17.684 minutes.

Table: Koc of the test item

Substance	tr,1 [min.]	tr,2 [min.]	mean tr [n=2]	log Koc	Koc
Reference substances
Formamide (t0)	1.538	1.497	1.518	-	-
Acetanilide	2.048	2.005	-	1.26
Monuron	2.555	2.501	-	1.99	-
2,5-Dichloroaniline	2.932	2.890	-	2.55	-
Naphthalene	3.432	3.381	-	2.75	-
Benzoic acid phenylester	4.106	4.017	-	2.87	-
Fenthion	5.637	5.540	-	3.31	-
Phenanthrene	6.264	6.123	-	4.09	-
4,4’-DDT	16.343	16.057	-	5.63	-
Test item
Test item – peak 1	17.785	17.582	-	5.58 *	3.8E+05

* Estimated value, calculated by extrapolation of the curve.

Validity criteria fulfilled:

not applicable

Conclusions:

The log Koc of the substance was determined to be >5 with an estimated value of 5.58. The respective Koc value is 380000 L/kg.

Executive summary:

The adsorption potential of the substance was determined in a study according to OECD 121 (HPLC method) and in compliance with GLP criteria. The mobile phase was 55/45 (v/v) methanol/water and the wavelength of detection 210 nm. The stationary phase contained cyanopropyl chains chemically bonded to silica. Duplicate measurements were performed. Both chromatograms of the test substance solution showed one test substance peak. The corresponding log Koc value was determined to be >5 with an estimated value of 5.58. The respective Koc value is 380000 L/kg.

Description of key information

The log Koc of the substance was determined to be >5 with an estimated value of 5.58. The respective Koc value is 380000 L/kg.

Key value for chemical safety assessment

Koc at 20 °C:

380 000

Additional information

The adsorption potential of the substance was determined in a study according to OECD 121 (HPLC method) and in compliance with GLP criteria. The mobile phase was 55/45 (v/v) methanol/water and the wavelength of detection 210 nm. The stationary phase contained cyanopropyl chains chemically bonded to silica. Duplicate measurements were performed. Both chromatograms of the test substance solution showed one test substance peak. The corresponding log Koc value was determined to be >5 with an estimated value of 5.58.The respective Koc value is 380000 L/kg.