A mixture of: 2,4 -bis(N'-(4-methylphenyl)ureido)toluene; 2,6 -bis(N'-(4-methylphenyl)ureido)toluene

Adsorption / desorption

Administrative data

Endpoint:

adsorption / desorption: screening

Type of information:

experimental study

Adequacy of study:

key study

Study period:

6 May 2003

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The study has been performed according to OECD and/or EC guidelines and according to GLP principles. Limited information available to verify the composition of the used test substance.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2003

Report date:

2003

Materials and methods

Test guideline

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

Test material

Test material information

Constituent 1

Reference substance name:

A mixture of: 2,4 -bis(N'-(4-methylphenyl)ureido)toluene; 2,6 -bis(N'-(4-methylphenyl)ureido)toluene

EC Number:

411-070-0

EC Name:

A mixture of: 2,4 -bis(N'-(4-methylphenyl)ureido)toluene; 2,6 -bis(N'-(4-methylphenyl)ureido)toluene

Molecular formula:

C23H24N4O2

IUPAC Name:

3-(2-methyl-5-{[(4-methylphenyl)carbamoyl]amino}phenyl)-1-(4-methylphenyl)urea

Details on test material:

- Name of test material (as cited in study report): KY-ET
- Substance type: white powder
- Physical state: solid
- Storage condition of test material: RT in the dark

Study design

Test temperature:

35 degrees C (column temperature)

HPLC method

Details on study design: HPLC method:

EQUIPMENT
- Apparatus: Hypersil BDS-CN
- Type: Column
- Type, material and dimension of analytical (guard) column: solid-phase = cyanopropyl chemically bound resin on silica basis; 150 x 4.6 (I.D.) mm; dp = 5 um
- Detection system: spectrophotometric (UV at wavelength 210 nm)

MOBILE PHASES
- Type: Eluent 55/45 methanol (HPLC-grade)/Milli-Q water
- Experiments with additives carried out on separate columns: no
- Solutes for dissolving test and reference substances: reference substance: methanol; test substance: DMSO

DETERMINATION OF DEAD TIME
- Method: by inert substances which are not retained by the column (5.2 g/L formamide in methanol diluted x10)

REFERENCE SUBSTANCES
- Identity:
Phenol (99%, Acros organics, Geel, Belgium)
N,N-dimethylbenzamide (98%, Acros organics, Geel, Belgium)
Methylbenzoate (99%, Acros organics, Geel, Belgium)
3,5-Dinitrobenzamide (97%, Acros organics, Geel, Belgium)
Naphthalene (99%, Acros organics, Geel, Belgium)
Mercaptodimethur (98.5%, Dr. Ehrenstorfer, Augsburg, Germany)
Fenthion (96%, Riedel-de Haen, Seelze, Germany)
Phenantrene (>98%, Acros organics, Geel, Belgium)
2,4-DDT (98%, Dr. Ehrenstorfer, Augsburg, Germany)

DETERMINATION OF RETENTION TIMES
- Quantity of test substance introduced in the column: 0.10 µg.
- Quantity of reference substances introduced in the column: 0.11 µg to 0.63 µg.

EVALUATION
- Calculation of capacity factors k': k'= (tr -t0)/t0 where t0 = retention time of unretarded component; tr = retention time of the substance
- Determination of the log Koc value: log k'= a * log Koc + b

Results and discussion

Adsorption coefficient

Adsorption coefficient 1

Type:

log Koc

Value:

2.94

Temp.:

35 °C

Remarks on result:

other: for Peak 1 (4% of total)

Adsorption coefficient 2

Type:

log Koc

Value:

3.13

Temp.:

35 °C

Remarks on result:

other: for Peak 2 (4% of total)

Adsorption coefficient 3

Type:

log Koc

Value:

3.53

Temp.:

35 °C

Remarks on result:

other: for Peak 3 (1% of total)

Adsorption coefficient 4

Type:

log Koc

Value:

3.84

Temp.:

35 °C

Remarks on result:

other: for Peak 4 (18% of total)

Adsorption coefficient 5

Type:

log Koc

Value:

4.33

Temp.:

35 °C

Remarks on result:

other: for Peak 5 (73% of total)

Results: HPLC method

Details on results (HPLC method):

- Retention times of reference substances used for calibration: Mean values =
Phenol = 2.33
N, N-dimethylbenzamide = 2.13
Methylbenzoate = 2.49
3,5-Dinitrobenzamide = 2.77
Naphtalene = 3.27
Mercaptodimethur = 3.08
Fenthion = 5.00
Phenantrene = 4.74
2,4-DDT = 8.28
- Note: According to the OECD 121 guideline, these reference substances are for Koc soil estimation
- Details of fitted regression line (log k' vs. log Koc): y = 0.318x - 1.33 (r = 0.94, n = 9)
- Average retention data for test substance: There were five peaks: Peak 1: 3.13 min., Peak 2: 3.31 min., Peak 3: 3.80 min., Peak 4: 4.26 min., Peak 5 (major peak): 5.28 min.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The log Kocs for all components of KY-ET were between 2.94 and 4.33. The main component (73%) showed a log Koc of 4.33.

Executive summary:

A adsorption-desorption study was performed according to OECD 121. There were no significant deviations impinging the reliability of the study. The log Koc was determined for all test substance peaks (5) and was between 2.94 and 4.33. The log Koc of the main component (73%) was 4.33.