2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-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:

2004

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))

GLP compliance:

yes

Type of method:

HPLC estimation method

Media:

soil

Test temperature:

25 °C

Details on study design: HPLC method:

APPARATUS AND CONDITIONS
- Apparatus: This method utilises a high performance liquid chromatograph with UV-VIS detector, reversed phase column and an aqueous mobile phase.
- Column: LiChrospher 100 CN, part, size 5 µm, 250 mm * 4 mm
- Mobile Phase: Methanol / water (55:45; v/v); adjusted to pH 8.5 with triethylamine
- Detection: 306 nm for the test item, 210 nm for the reference items and for sodium nitrate
- Temperature: 25°C
- Injection Volume: 20 µl
- Flow: 1.0 ml/min

DETERMINATION OF DEAD TIME
- Method: measured of the retention time of sodium nitrate

REFERENCE SUBSTANCES: Acetanilide, Linuron, Isoproturon, Fenthion, 2.4-DDT, Sodium nitrate

EVALUATION
- Calculation of capacity factors k': HPLC retention time of the test or reference items - HPLC dead time / HPLC dead time
- Determination of the log Koc value: Distribution coefficient (Kd) / organoc carbon content (OC)

Analytical monitoring:

no

Details on test conditions:

TEST ITEM SOLUTION
The test substance (32.99 mg) was dissolved in methanol (100 ml) to prepare a stock solution of 329.9 µg/ml. The stock solution (7 ml) was diluted with mobile phase to 100 ml. The pH value of the test item solution was determined to be 8.83. The test item solution was injected three times.

REFERENCE SOLUTION
- Stock solutions of the reference items in methanol were prepared as described:
- 10.78 mg of the reference item isoproturon, 10.72 mg of linuron, 10.87 mg 2,4-DDT,11.0 mg of acetanilide, 10 µl fenthion and 10,3 mg Naphtalene were each dissolved in 10 ml methanol.
- A combined reference solution was prepared by transferring 188 µI of the isoproturon stock solution, 106 µl of linuron stock solution, 24.6 µI 2,4-DDT stock solution, 297 µl of acetanilide stock solution, 124 µl of the fenthion stock solution and 30.7 µl Naphtalene stock solution into one volumetric flask and diluted to a volume of 10 ml with eluent. This reference solution was injected eight times.
Sodium nitrate (5.51 mg) was diluted to 50 ml with methanol to obtain a stock solution. The stock solution (498 µI) was diluted to 10 ml with eluent. This sodium nitrate solution was injected four times and was used for the determination of the dead time of the HPLC system.

Type:

log Koc

Value:

2.8

Temp.:

25 °C

Type:

Koc

Value:

626

Temp.:

25 °C

Validity criteria fulfilled:

not specified

Conclusions:

The log koc of the test material was determined to be 2.8 under the conditions of the test.

Description of key information

The study provided was conducted to recognised testing guidelines and with GLP certification.

Key value for chemical safety assessment

Koc at 20 °C:

2.8

Additional information

The log Koc of the test substance measured in a GLP study according to OECD 121 was 2.8 (corresponding Koc = 626), hence, significant adsorption of the substance to soil particles is not likely (RCC, 2004).