Registration Dossier

Diss Factsheets

Physical & Chemical properties

Partition coefficient

Currently viewing:

Administrative data

Link to relevant study record(s)

Reference
Endpoint:
partition coefficient
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2000-01-31 - 2000-02-02 (experimental phase)
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Qualifier:
according to guideline
Guideline:
OECD Guideline 107 (Partition Coefficient (n-octanol / water), Shake Flask Method)
Deviations:
no
Qualifier:
according to guideline
Guideline:
EU Method A.8 (Partition Coefficient)
Deviations:
no
Qualifier:
according to guideline
Guideline:
EPA OPPTS 830.7550 (Partition Coefficient, n-octanol / H2O, Shake Flask Method)
Deviations:
no
GLP compliance:
yes
Type of method:
shake-flask method to: flask method
Partition coefficient type:
octanol-water
Analytical method:
high-performance liquid chromatography
Type:
log Pow
Partition coefficient:
5.24
Temp.:
25 °C
pH:
5
Type:
log Pow
Partition coefficient:
5.2
Temp.:
25 °C
pH:
7
Type:
log Pow
Partition coefficient:
5.23
Temp.:
25 °C
pH:
9.1
Details on results:
CGA185072 is a weak base (pKa: 3.55). Therefore the partition coefficients at 25 °C were determined as uncorrected and as corrected values for three different pH values (i.e. after correction for the effects due to protonation of the base).
The mean Pow and log Pow (logarithm to base 10) values for each of the three octanol / buffer solution systems are given below, together with the mean determined pH values, all correct to three significant figures. The figure in parentheses represents the standard deviation.

pH: 5.0
uncorrected Pow: 172000 (17300)
corrected Pow: 178000 (17900)
uncorrected log Pow: 5.24
corrected log Pow: 5.25

pH: 7.0
uncorrected Pow: 159000 (14600)
corrected Pow: 159000 (14600)
uncorrected log Pow: 5.20
corrected log Pow: 5.20

pH: 9.1
uncorrected Pow: 169000 (24200)
corrected Pow: 169000 (24200)
uncorrected log Pow: 5.23
corrected log Pow: 5.23

Because CGA185072 is only a weak base, the uncorrected and corrected values are practically identical.

Within the investigated pH range, the octanol/water partition coefficient is practically independent of the pH of the aqueous phase.

Conclusions:
The study is considered to be adequate and reliable.
Executive summary:

log Pow  =  5.24 at pH 5.0
log P
ow  =  5.20 at pH 7.0
log P
ow  =  5.23 at pH 9.1

Within the investigated pH range, the octanol/water partition coefficient is practically independent of the pH of the aqueous phase.

Description of key information

log Pow (25°C, pH 5.0): 5.24

log Pow (25°C, pH 7.0): 5.20

log Pow (25°C, pH 9.1): 5.23

Key value for chemical safety assessment

Log Kow (Log Pow):
5.2
at the temperature of:
25 °C

Additional information

Within the investigated pH range, the octanol/water partition coefficient is practically independent of the pH of the aqueous phase.

A guideline study is available which is considered to be reliable and adequate, and is carried forward for use in risk assessment, classification and labelling.