Registration Dossier

Environmental fate & pathways

Adsorption / desorption

Currently viewing:

Administrative data

Endpoint:
adsorption / desorption: screening
Type of information:
experimental study
Adequacy of study:
key study
Study period:
25 November and 9 December 1996
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Study was conducted according to an OECD Method and in accordance with GLP. The study material is well characterized.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1997
Report Date:
1997

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
EU Method C.19 (Estimation of the Adsorption Coefficient (KOC) on Soil and Sewage Sludge Using High Performance Liquid Chromatography (HPLC))
Qualifier:
according to
Guideline:
OECD Guideline 121 (Estimation of the Adsorption Coefficient (Koc) on Soil and on Sewage Sludge using High Performance Liquid Chromatography (HPLC))
Principles of method if other than guideline:

The soil adsorption coefficient was determined by the high performance liquid chromatography (HPLC) method as described in OECD draft document TGP/94.75 (April 1994).
GLP compliance:
yes
Type of method:
HPLC estimation method
Media:
soil

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: particulate/powder
Remarks:
migrated information: powder
Details on test material:
Intended use: Pharmaceutical intermediate
Appearance: White powder
Storage conditions: Room temperature
Expiry date: Not supplied
Purity: 99.4%
Date received: 2 October 1996
Radiolabelling:
no

Study design

Test temperature:
No data

HPLC method

Details on study design: HPLC method:
The soil adsorption coefficient is defined as the ratio between the concentration of the test substance in the soil and the concentration of the test substance in the aqueous phase, both measured when the adsorption equilibrium is reached
Column: Cyano Spherisorb, 25 cm x 4.6 mm id, 5 µm particle size.

Mobile phase: 55 : 45 v/v potassium dihydrogen citrate buffer (O.OlM) at pH 6: methanol.

Flow rate: 1.0 ml/min.

Pressure: 2500 psi.

Analytical wavelength: 245 nm.

Injection volume: 10 µI.

Range: -10 to 500 mV.

Batch equilibrium or other method

Analytical monitoring:
yes
Details on sampling:
Autosampler: Model 712 WISP, Waters Associates
Details on matrix:
No Data
Details on test conditions:
PREPARATION OF TEST SOLUTION

Test substance (0.10971 g) was weighed into a volumetric flask (100 ml) dissolved in and made to volume with methanol.

An aliquot (15 ml) of this solution was diluted to 100 ml with mobile phase.

The quantity oftest substance introduced onto the HPLC column in a 10 µl injection was 1645.7 ng.
Computational methods:
No Data

Results and discussion

Adsorption coefficientopen allclose all
Type:
Koc
Value:
< 60.3
Remarks on result:
other: PH 7
Type:
log Koc
Value:
< 1.78
Remarks on result:
other: PH 7

Results: HPLC method

Details on results (HPLC method):
Calibration data for the reference compounds are given in Table 6. The dead time (t0) was determined as 3.109 minutes (mean of3.110 and 3.107 minutes). The mean retention times of the reference compounds were Monolinuron 5.762 minutes and Isoproturon 6.365 minutes. A mean retention time of 3.280 minutes was obtained, indicating that the test substance was hardly retained. The retention time ofUK-143,108 is less than the lowest available standard (Monolinuron) and is therefore considered to have a soil adsorption coefficient less than that of Monolinuron ie Koc value less than 60.3, log Koc value less than 1.78.

Results: Batch equilibrium or other method

Adsorption and desorption constants:
No Data
Recovery of test material:
No Data
Concentration of test substance at end of adsorption equilibration period:
No Data
Concentration of test substance at end of desorption equilibration period:
No Data
Details on results (Batch equilibrium method):
No Data
Statistics:
No Data

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
The soil adsorption coefficient for UK-143,108 has been determined as:
Log Koc< 1.78 at pH 7
Koc < 60.3 at pH 7

The result indicates that the test substance is likely to be moderately or highly mobile in soil.