Registration Dossier

Administrative data

Endpoint:
adsorption / desorption: screening
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1995
Report Date:
1995

Materials and methods

Test guideline
Qualifier:
equivalent or similar to
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 material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: particulate/powder
Remarks:
migrated information: powder
Details on test material:
- Name of test material (as cited in study report): Carboxyethylisothiuroniumbetain
- Physical state: powder
- Analytical purity: > 98%
- Impurities (identity and concentrations): < 1% thiocarbamide
- Lot/batch No.: 88-3054
Radiolabelling:
no

Study design

Test temperature:
not specified

HPLC method

Details on study design: HPLC method:
EQUIPMENT
- Apparatus: HP 1090 (liquid chromatopraph)
- Type, material and dimension of analytical (guard) column: 125 mm x 4 mm cyanopropyl, 5 µm diameter (LiChrospher 100 CN, Merck)
- Detection system: UV

MOBILE PHASES
- Type: stationary phase
- Experiments with additives carried out on separate columns: no
- pH: Citrate buffer, pH = 7.0
- Eluent: 60 vol .-%: 10 mmol/L. 40 vol .-%: acetonitrile
- Flow rate: 1 mL/min
- Injection volume: 25 µL
- Calculation of retention times: 0.814 – 0.914 min

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

REFERENCE SUBSTANCES
- Identity: Monolinuron, Atrazin, Isoproturon, Monuron, Carbendazim, Tradimenol, Fenamiphos, Triadimefon, Linuron, Fensulfothion, Mercaptodimetur, Fuberidazol, Disulfoton, Azinphos-methyl, Isofenphos, Fenthion, Pyrazophos, Anthrachinon, Trifluralin, alpha-Endosulfan, Quintozen, Sulprofos

DETERMINATION OF RETENTION TIMES
- Quantity of test substance introduced in the column: 22.5 mg in 1000 mL
- Quantity of reference substances: In each case, approximately 5 to 25 mg were weighed, transferred to a 10 mL volumetric flask and make up to the mark with water.

REPETITIONS
- Number of determinations: 2

EVALUATION
- Calculation of capacity factors k': k' = (tr-to)/to [tr =n retention time of test substance, to = retention time of nitrate]
- Determination of the log Koc value: log Koc = logK'/(slope+axis intercept)

Results and discussion

Adsorption coefficient
Type:
log Koc
Value:
-0.4

Results: HPLC method

Details on results (HPLC method):
- Retention times of reference substances used for calibration: see attachment
- Details of fitted regression line (log k' vs. log Koc): y = 0.2381x-0.1805, R2 = 0.5352
- Average retention data for test substance: 1.396 min

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
The log Koc value is determined to be - 0.4.