Registration Dossier

Administrative data

Endpoint:
partition coefficient
Type of information:
experimental study
Adequacy of study:
key study
Study period:
1999-12-01 to 2000-08-07
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2000
Report Date:
2000

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 107 (Partition Coefficient (n-octanol / water), Shake Flask Method)
Version / remarks:
(1995)
Qualifier:
according to
Guideline:
EU Method A.8 (Partition Coefficient)
Version / remarks:
(1992)
Qualifier:
according to
Guideline:
EPA OPPTS 830.7550 (Partition Coefficient, n-octanol / H2O, Shake Flask Method)
Version / remarks:
(1996)
GLP compliance:
not specified
Type of method:
flask method
Partition coefficient type:
octanol-water

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: particulate/powder

Study design

Analytical method:
photometric method

Results and discussion

Partition coefficient
Key result
Type:
log Pow
Partition coefficient:
0.5
pH:
> 6 - < 7
Remarks on result:
other: Temperature not mentioned

Any other information on results incl. tables

Data handling: The partition coefficient is defined as the ratio of the equilibrium concentrations of a dissolved item in a two phase system consisting two largely immiscible solvents. In the case of n-octanol and water: Pow = Cn-Octanol/CWater; the partition coefficient is dimensionless and usually given in form of its logarithm to base ten. A Pow is calculated from data of each run. Altogether six values are obtained for each experiment. The six log Pow values should fall within a range of +-0.3 units.

The partition coefficient of the test item was determined using the shake flask method. The partition coefficient was calculated based on the concentration measured in the two phases of the system. Basing on the results of photometrical measurements the concentration of the test item was determined using a calibration curve (calibration range: 2.5 to 25 mg test item/L (deionised water or n-octanol)). The determination of concentration was conducted via correlation of absorbtion units (AU) of different standard solutions with their corresponding concentrations, using a linear regression (R2 > 0.995).

Applicant's summary and conclusion

Conclusions:
According to this study the logarithmic partition coefficient (n-octanol/water) of the test item was determined to be 0.5 using the shaking flask method.