N,N''-(methylenedi-4,1-phenylene)bis[N'-octyl]urea

Adsorption / desorption

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

adsorption / desorption: screening

Type of information:

experimental study

Adequacy of study:

key study

Study period:

14 March 2003 - 18 March 2003

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

GLP compliance:

yes

Type of method:

HPLC estimation method

Media:

soil

Radiolabelling:

no

Test temperature:

26 ± 1°C

Details on study design: HPLC method:

EQUIPMENT
- Apparatus: P1000 pump equipped with AS 3000 injector and UV 6000 detector (all Thermofinnigan); data acquisition software: Chromquest v 2.51 (Thermofinnigan)
- Type: HPLC-UV
- Column: Zorbax CN, 150 x 4.6 mm, dp=5 µm (Interchim)
- Detection system: UV; test item at 254 nm, reference item and t0-marker at 210 nm

MOBILE PHASES
- Type: methanol/water 55/45 (v/v)
- Experiments with additives carried out on separate columns: no
- pH: neutral
- Solutes for dissolving test and reference substances: all stock solutions in methanol, all test solutions were prepeared from stock solutions by dilution with methanol/water 55/45 (v/v)

DETERMINATION OF DEAD TIME
- Method: by inert substance which is not retained by the column, i.e. N,N-dimethylformamide

REFERENCE SUBSTANCES
- Identity:
Acetanilide - log Koc = 1.25
Methylbenzoate - log Koc = 1.80
Napthalene - log Koc = 2.75
1,2,3-trichlorobenzene - log Koc = 3.16
Phenanthrene - log Koc = 4.09
D.D.T. - log Koc = 5.63

DETERMINATION OF RETENTION TIMES
- Quantity of test substance introduced in the column: 97800 ng
- Quantity of reference substances introduced in the column:
Acetanilide: 17.8 ng
Methylbenzoate: 33.6 ng
Napthalene: 4.10 ng
1,2,3-trichlorobenzene: 22.4 ng
Phenanthrene: 16.3 ng
D.D.T.: 16.2 ng
- Intervals of calibration: reference substances were injected as a mixed standard; duplicate calibration injections before and after injections of the test item; all injections were carried out on the same day

REPETITIONS
- Number of determinations (test item, reference substances and t0-marker): 2

EVALUATION
- Calculation of capacity factors k': k'= (tr-t0)/t0
- Retention times: directly from HPLC chromatogram, in minutes
- Determination of the log Koc value of test item: plot log k' data of reference substances against their log Koc values as described in guidelines (soil reference); use log k' of test item to derive log Koc value from plot

Type:

Koc

Value:

57 543

Temp.:

20 °C

Remarks on result:

other: component 1

Type:

log Koc

Value:

4.76

Temp.:

20 °C

Remarks on result:

other: component 1

Type:

Koc

Value:

> 426 580

Temp.:

20 °C

Remarks on result:

other: components 2 and 3

Type:

log Koc

Value:

> 5.63

Temp.:

20 °C

Remarks on result:

other: components 2 and 3

Details on results (HPLC method):

- Retention times of reference substances used for calibration:
t0-marker: 1.97 min
Acetanilide: 2.59 min
Methylbenzoate: 3.35 min
Napthalene: 5.78 min
1,2,3-trichlorobenzene: 6.82 min
Phenanthrene: 11.55 min
D.D.T.: 30.36 min
- Average retention data for test substance: 18.82 min
- Details of fitted regression line (log k' vs. log Koc): Regression equation: log Koc = 2.659 * log k' + 2.286 (R^2 = 0.978)

The test substance is a multi-constituent substance containing three main constituents. Only for one of the three constituents a retention time between acetanilide and D.D.T. was found. The identity of this constituent was not determined. The retention time of the two other constituents was higher than that of DDT, and hence the log Koc of these two not further specified constituents was > 5.63.

Validity criteria fulfilled:

yes

Conclusions:

The test substance is a multi-constituent substance containing three main constituents. Only for one of the three constituents a retention time between acetanilide and D.D.T. was found. Thus the adsorption coefficient on soil for this constituent of KY-EU was calculated: the estimated values for Koc and log Koc are 57543 and 4.76, respectively. The retention time of the two other constituents was higher than that of DDT (log Koc = 5.63), and hence the Koc and log Koc values (based on soil reference data) of these two constituents of KY-EU are > 426580 and > 5.63, respectively.

Reference 2

Endpoint:

adsorption / desorption: screening

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

other:

Description of key information

The log Koc of a constituent of the substance is 4.76 and the log Koc of the other 2 constituents of the substance is >5.63.

Additional information

A study in accordance with OECD 121 was performed. The substance contains three main constituents. Only for one of the three constituents a retention time between acetanilide and DDT was found. Thus the adsorption coefficient on soil for this constituent of KY-EU was calculated: the estimated values for Koc and log Koc are 57543 and 4.76, respectively. The retention time of the two other constituents was higher than that of DDT (log Koc = 5.63), and hence the Koc and log Koc values (based on soil reference data) of these two constituents of KY-EU are > 426580 and > 5.63, respectively.