A mixture of: isomers of 2-(2H-benzotriazol-2-yl)-4-methyl-(n)-dodecylphenol; isomers of 2-(2H-benzotriazol-2-yl)-4-methyl-(n)-tetracosylphenol; isomers of 2-(2H-benzotriazol-2-yl)-4-methyl-5,6-didodecyl-phenol. n=5 or 6

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:

1995-12-12 to 1995-12-21

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP and guideline study

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 121 (Estimation of the Adsorption Coefficient (Koc) on Soil and on Sewage Sludge using High Performance Liquid Chromatography (HPLC))

Deviations:

not applicable

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC estimation method

Media:

soil

Radiolabelling:

no

Test temperature:

40°C (HPLC)

Details on study design: HPLC method:

EQUIPMENT
- Apparatus: M 480 (Gynkotek, Munich, BRD)
- Type: HPLC
- Type, material and dimension of analytical (guard) column: 250 mm X 4.6 mm; 5 µm Cyanopropyl Zorbax CN (VDS Optilab, Berlin, BRD)
- Detection system: Diode array detector UVD 320 (Gynkotek, Munich, BRD)

MOBILE PHASES
- Type: Methanol: 0.01 mol/l citrate buffer pH 6.0 (75 : 25 / v:v) including 0.5 mmol/l triethylamine as a modifier 1.0 mL/min

DETERMINATION OF DEAD TIME
- Method: by inert substances which are not retained by the column

REFERENCE SUBSTANCES
- Identity:
1,2,3-trichlorobenzene
Fenthion
Acenaphthene
Phenanthrene
Hexachlorobenzene
Pyrene
4,4'-DDT

DETERMINATION OF RETENTION TIMES
- Quantity of test substance introduced in the column: A stock solution of the test substance was prepared by dissolving 7.98 mg in 10 mL tetrahydrofurane. 250 µL ofthe stock solution were diluted to 10 ml with methanol. An aliquot of this solution was chromatographed under standard chromatographic conditions and the retention time of the test substance was determined.
- Quantity of reference substances: A stock solution of each reference substance was prepared by dissolving approximately 10 mg in 10 ml methanol. The stock solutions were diluted 1:100 with methanol.

REPETITIONS
- Number of determinations: 1

EVALUATION
- Calculation of capacity factors k': yes
- Calculation of retention times: yes
- Determination of the log Koc value: yes

Type:

log Koc

Value:

> 5.6

Temp.:

40 °C

Details on results (HPLC method):

- Retention times of reference substances used for calibration:
1,2,3-trichlorobenzene : 4.85 min
Fenthion: 5.56 min
Acenaphthene: 5.28 min
Phenanthrene: 6.14 min
Hexachlorobenzene: 6.66 min
Pyrene: 7.36 min
4,4'-DDT: 8.47 min
- Details of fitted regression line (log k' vs. log Koc):
Linear regression analysis provides the following parameters:
log KQC = 5.60 x log k' + 3.85
coefficient of correlation = 0.971
- Average retention data for test substance: 21.50 min

Description of key information

Adsorption to solid soil phase is expected. 

Additional information

Adsorption/Desoprtion of the test item on soil was determined in a study according to OECD Guideline 106. As a result of this study the following estimation of the adsorption-coefficient (log Koc) of the test substance could be made: log Koc is higher than 5.6.