Registration Dossier

Administrative data

Endpoint:
partition coefficient
Type of information:
experimental study
Adequacy of study:
key study
Study period:
02/12/2008 to 17/02/2009
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Study conducted to GLP in accordance with recognised guideline.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2009
Report Date:
2009

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
EU Method A.8 (Partition Coefficient)
Deviations:
no
GLP compliance:
yes (incl. certificate)
Type of method:
shake-flask method to: flask method
Partition coefficient type:
octanol-water

Test material

Reference
Name:
Unnamed
Type:
Constituent

Study design

Analytical method:
high-performance liquid chromatography

Results and discussion

Partition coefficient
Type:
log Pow
Partition coefficient:
< -2.93
Temp.:
22.7 °C
pH:
ca. 7
Details on results:
No test material was detected in any of the organic phase samples; therefore, the sample responses were considered to be lower than the limit of detection (LOD), considered as the lowest total area noted for the linearity standard of lowest concentration. This would give a worst case scenario for the partition coefficient endpoint.
The analytical method was based on a method supplied by the Sponsor; the complex chromatographic profile was considered to be due to the complex nature of the test material.
Substances having a log10 Pow of greater than 3 are regarded as having the potential to bioaccumulate in the environment.
It is evident from the information obtained in the hydrolysis test and data relating to the pH of the test material in water that negligible hydrolysis of the sample solutions occurred during the course of the partition coefficient test.
The test was carried out at a pH of approximately 7, as recommended for salts (except for Sample 5); However, the effect of pH was considered to be negligible as the dissociation constants of the test material would ensure that it was in an ionised state across the entire environmentally relevant pH range.

Any other information on results incl. tables

HPLC results:

Organic Phase: The linearity of the detector response with respect to concentration was assessed over the concentration range of 0 to 1.01 x 103mg/l. This was satisfactory with a correlation coefficient of 1.000 being obtained.

Aqueous Phase: The linearity of the detector response with respect to concentration was assessed over the concentration range of 0 to 1.02 x 103mg/l. This was satisfactory with a correlation coefficient of 1.000 being obtained.

The definitive test results indicated that virtually all of the test material remained in the aqueous phases, and all of the test material used in the samples was fully recovered. Thus, it was decided that recovery of analysis for the organic phase extraction procedure was not required.

The partition coefficient determined for each sample is shown in the following table:

Sample Number

Organic/Aqueous VolumeRatio

Partition Coefficient

Log10, Pow

Mean Partition Coefficient

1

10:1

<1.48x10-3

<1.49x10-3

<-2.83

<-2.83

<1.49x10-3

 

2

3

40:1

<1.42x10-3

<1.39x10-3

<-2.85

<-2.86

<1.42x10-3

 

4

5

20:1

<1.49x10-3

<1.44x10-3

< -2.85

<-2.84

<1.44x10-3

 

6

 

Applicant's summary and conclusion

Conclusions:
The partition coefficient of the test material has been determined to be < 1.49 x 10E-3 at 22.7 ºC, log10 Pow <-2.83.
Executive summary:

In a determination of general physico-chemical properties study (Harlan project number: 0959/0224) the test material is shown to have a partition coefficient of less than 1.49 x 10-3at 22.7 ± 1.0°C, log10Pow< -2.83.

The determination was carried out using the shake-flask method, Method A8 Partition Coefficient of Commission Regulation (EC) No 440/2008 of 30 May 2008.