Tetrahydro-3-pentyl-2H-pyran-4-yl acetate

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:

07 May - 09 June 2015

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:

(2001)

Deviations:

no

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

GLP compliance:

yes

Type of method:

HPLC estimation method

Media:

other: soil adsorption reference data

Radiolabelling:

no

Test temperature:

35°C ± 1°C

Details on study design: HPLC method:

EQUIPMENT
- Instrument: Acquity UPLC system (Waters, Milford, MA, USA)
- Detector: Acquity UPLC TUV detector (Waters)
- Column: Acquity UPLC HSS Cyano, 100 mm x 2.1 mm i.d., dp = 1.8 μm (Waters)
- Flow: 0.4 mL/min
- Injection volume: 5 µL
- UV detection: 210 nm

MOBILE PHASE
- Type: 30/70 (v/v) methanol/water
- pH: neutral (no buffers used)
- Solutes for dissolving test and reference substances: stock solutions in methanol; end solutions in 30/70 (v/v) methanol/water

DETERMINATION OF DEAD TIME
- Method: by inert substance which is not retained by the column (formamide)

REFERENCE SUBSTANCES
- Identity: Acetanilide; Monuron; 2,5-Dichloroaniline; Naphthalene; Benzoic acid phenylester; Fenthion.
- The blank solution for the mixture of reference substances was 30/70 (v/v) methanol/water.

PREPARATION OF TEST SOLUTIONS
- A 2000 mg/L test substance stock solution in methanol was diluted to obtain a solution of 100 mg/L in 30/70 (v/v) methanol/water.
- The test substance blank solution was 30/70 (v/v) methanol/water.

REPETITIONS
- Number of determinations: 2 (for reference substances and test solutions); 1 (for blank solution)

EVALUATION
- Calculation of capacity factors k': k'= (tr-t0)/t0 where tr = reterntion time, t0 = mean column dead time
- Determination of the log Koc value: via linear regression; log k' = 0.728 x log Koc - 0.924 (r = 0.942, n = 12)

Key result

Type:

log Koc

Value:

2.37

Temp.:

35 °C

Remarks on result:

other: peak 1 in HPLC test; Peak area: 3.4%. Koc= 240.

Type:

log Koc

Value:

2.42

Temp.:

35 °C

Remarks on result:

other: peak 2 in HPLC test; Peak area: 33%. Koc= 260.

Type:

log Koc

Value:

2.51

Temp.:

35 °C

Remarks on result:

other: peak 3 in HPLC test; Peak area: 8.3%. Koc= 320.

Type:

log Koc

Value:

2.87

Temp.:

35 °C

Remarks on result:

other: peak 4 in HPLC test; Peak area: 16%. Koc= 730.

Type:

log Koc

Value:

2.88

Temp.:

35 °C

Remarks on result:

other: peak 5 in HPLC test; Peak area: 40%. Koc= 760.

Details on results (HPLC method):

In the HPLC chromatograms of the test substance solution, several test substance peaks were observed. Measurements and results are summarized in the table below.

The test was performed at 35°C (i.e. the temperature of the column), but the log Koc value(s) obtained can be considered to represent the value(s) at an unspecified, probably ambient temperature (ca. 20°C) since no mention is made in the guidelines of the temperature at which the reference substance’s log Koc values were determined. Adsorption coefficients of the test and reference substances are assumed to vary with temperature in the same way.

Substance	tr,1 [min]	tr,2 [min]	mean tr [min] (n=2)	log Koc	Koc	Area %
Formamide (t0)	0.677	0.680	0.679
Acetanilide	1.512	1.575		1.26
Monuron	2.992	3.217		1.99
2,5-Dichloroaniline	3.692	3.940		2.55
Naphthalene	5.784	6.302		2.75
Benzoic acid phenylester	12.075	13.654		2.87
Fenthion	32.468	38.141		3.31
Test substance – peak 1	5.012	4.980	4.996	2.37	2.4 x 10^2	3.4
Test substance – peak 2	5.346	5.309	5.328	2.42	2.6 x 10^2	33
Test substance – peak 3	6.104	6.063	6.084	2.51	3.2 x 10^2	8.3
Test substance – peak 4	10.571	10.495	10.533	2.87	7.3 x 10^2	16
Test substance – peak 5	10.880	10.786	10.833	2.88	7.6 x 10^2	40

Remark: Log Koc values are based on soil adsorption reference data (according to OECD 121)

A typical chromatogram is presented in the 'attached backgorund material'.

Validity criteria fulfilled:

yes

Conclusions:

Based on the HPLC estimation method at neutral pH using soil-adsorption reference data, the log Koc for Jasmal was determined to be in the range 2.37-2.88 (covering 98.7% of the substance).

Executive summary:

The HPLC estimation method at neutral pH using soil-adsorption reference data was applied for the determination of the adsorption coefficient (Koc) of the substance. The study was performed according to EC C.19 and OECD 121 and in accordance with the principles of GLP.The mobile phase was 30/70 (v/v) methanol/water. The column temperature was 35°C. In the HPLC chromatogram of the test substance solution, three major peaks (16, 33 and 40% peak area) and 2 smaller peaks (3.4 and 8.3% peak area) were observed. The log Koc values of the major components range from 2.42 - 2.88 (Koc: 260 - 760). The log Koc values of the minor components range from 2.37 - 2.51 (Koc ranges from 240 to 320). The Koc of 2.37 will be used for the risk assessment as the lower value is anticipated to be related to the main trans-isomer.

Description of key information

The HPLC estimation method at neutral pH using soil-adsorption reference data was applied for the determination of the adsorption coefficient (Koc) of the substance. The study was performed according to EC C.19 and OECD 121 and in accordance with the principles of GLP.The mobile phase was 30/70 (v/v) methanol/water. The column temperature was 35°C. In the HPLC chromatogram of the test substance solution, three major peaks (16, 33 and 40% peak area) and 2 smaller peaks (3.4 and 8.3% peak area) were observed. The log Koc values of the major components range from 2.42 - 2.88 (Koc: 260 - 760). The log Koc values of the minor components range from 2.37 - 2.51 (Koc ranges from 240 to 320). The Koc of 2.37 will be used for the risk assessment as the lower value is anticipated to be related to the main trans-isomer.

Key value for chemical safety assessment

Koc at 20 °C:

760

Additional information

The highest Koc and log Koc are reported as key value for chemical safety assessment. This is also the Koc/Log Koc for the constituent with the highest response (40% peak area) in the HPLC test.

[LogKoc: 2.88]