Registration Dossier

Administrative data

Endpoint:
adsorption / desorption
Remarks:
adsorption/desorption
Type of information:
experimental study
Adequacy of study:
key study
Study period:
Testing phase 2005-09-01 to 2005-10-13. Final report completed and signed 2005-11-30.
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Meets the criteria for classification as Reliable without restriction according to Klimisch et al (1997)

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2005
Report Date:
2005

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
other: 2001/59/EEC, C19
Deviations:
no
GLP compliance:
yes
Type of method:
HPLC estimation method
Media:
other: HPLC

Test material

Reference
Name:
Unnamed
Type:
Constituent

Study design

Test temperature:
HPLC Column temperature 40 C

HPLC method

Details on study design: HPLC method:
EQUIPMENT
- Apparatus: A HPLC system comprising of the following components - autosampler, workstation, Phenosphere Next 5u CN column (250 x 4.6 x mm id)
- Injection volume 10ul.
- UV detector wavelength: Dead time and reference standards 210nm, sample 254nm.

MOBILE PHASES
- Type: Methanol:Reverse osmosis water (55:45 v/v) adjusted to pH 7 with 1M sodium hydroxide pumped at a flow rate of 1ml/min

DETERMINATION OF DEAD TIME
- Method: by means of inert substances (Formamide) which are not retained by the column.

REFERENCE SUBSTANCES
- Identity: Acetanilide, Phenol, Isoproturon, Triadimenol, Linuron, Naphthalene, Endosulfan-diol, Fenthion, Endosulfan, Phenanthrene, Diclofop-methyl, DDT.

REPETITIONS
- Number of determinations: two

EVALUATION
- Calculation of capacity factors k': (retention time of test substance - column dead time)/ column dead time
- Calculation of retention times: measured by HPLC
- Determination of the log Koc value: Determined from equation of the line from the calibration graph of logKoc versus logk'

Batch equilibrium or other method

Analytical monitoring:
no

Results and discussion

Adsorption coefficientopen allclose all
Type:
log Koc
Value:
< 1.25
Temp.:
40 °C
Type:
Koc
Value:
< 17.8
Temp.:
40 °C

Results: HPLC method

Details on results (HPLC method):
- Retention times of reference substances used for calibration (min):
Acetanilide 3.78
Phenol 3.68
Isoproturon 4.597
Triadimenol 5.33
Linuron 5.44
Naphthalene 5.97
Endosulfan-diol 6.52
Fenthion 8.10
Endosulfan 13.33
Phenanthrene 10.02
Diclofop-methyl 12.62
DDT 38.01

- Details of fitted regression line (log k' vs. log Koc): r=0.991

- Average retention data for test substance: Injection 1) 1.609 min, injection 2) 1.612 min.

Any other information on results incl. tables

The low adsorption properties of the test material containing salted sulfonic acid functional groups deterimined by the HPLC estimation method were consistent with the extremely high water solubility and low partition coefficient characteristics. Although the determined value is believed to accurately assess the affinity of the test material for the organic carbon content of soils and sewage sludge, the method guideline specifically requiring the analysis of substances in an ionised form if present within the environmentally relevant pH range of 5.5 to 7.5: the mobility of the test material in soil and sewage sludge may also be influenced by additional interactions other than partitioning not addressed by the the test method, due to the anionic nature of the test material.

The alternative use of computer-based estimation programs and/or Quantitive Structure Activity Relationships (QSAR's) for materials of this nature are considered invalid as estimates are typically derived from the partition coefficient value. Therefore once more the possible secondary interaction originating from the anionic charges present on the test material are not addressed.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
The adsorption coefficient of the test material has been determined to be <17.8, log10 Koc <1.25.
Executive summary:

Introduction

This study was undertaken to determine th adsorption coefficient (Koc) of the test substance using a High Performance Liquid Chromotography (HPLC) correlation technique. The method was designed to be compatible with the following:

Method C19 of Commission Directive 2001/59/EC (which constitutes Annex V of Council Directive 67/548/EEC).

Results and Conclusions

The adsorption coefficient (Koc) of the test material was determined to be <17.8. The log10 Koc was determined to be <1.25.