Registration Dossier

Administrative data

Endpoint:
partition coefficient
Type of information:
experimental study
Adequacy of study:
key study
Study period:
13.10.2005 - 07.12.2005
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: According to OECD guideline under GLP
Cross-referenceopen allclose all
Reason / purpose:
reference to same study
Reason / purpose:
reference to other study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2006
Report Date:
2006

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 107 (Partition Coefficient (n-octanol / water), Shake Flask Method)
Deviations:
yes
Remarks:
see below
Principles of method if other than guideline:
In principle, the log P(ow) can be determined by the flask shaking method (log P(ow) between -2 and 4, OECD guideline 107) or alternatively, by the
HPLC - method as described in OECD guideline No. 117 (log P(ow) between 0 and 6). Limitations and gaps of both methods are described in the
guidelines.
In the preliminary test, a poor solubility in water and a very good solubility in n-octanol were found indicating a partition coefficient of above 5.9.
As the solubility in n-octanol was determined to be > 527 g/l, the true log P(ow) is far above 5.9. Hence, a main test according to OECD Guidelines 107/ 117 could not be applied. Therefore the partition coefficient of Dihydro-C14-Aldehyde was estimated using the solubility data in n-octanol
and in water.
GLP compliance:
yes (incl. certificate)
Type of method:
other: see below
Partition coefficient type:
octanol-water

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
- Name of test material (as cited in study report): Dihydro-C14-aldehyde
- Storage: At room temperature at about 20°C (in a closed screw-top bottle under nitrogen)

Study design

Analytical method:
gas chromatography

Results and discussion

Partition coefficient
Key result
Type:
log Pow
Partition coefficient:
> 5.9
Temp.:
20 °C
pH:
7
Details on results:
In the present study, the n-octanol solubility of Dihydro-C14-Aldehyde was determined to be > 526.5 g/l. After the incubation time, the test item was
completely dissolved by visual judgement.
The correlation coefficient r² fit was 0.9998 (optimum = 1.0000). This reflects the linearity of the GC-system within the calibration range of 0.325 µg/ml to 8.118 µg/ml of the test item.

Any other information on results incl. tables

No remarks

Applicant's summary and conclusion

Conclusions:
In conclusion, the partition coefficient, log POW, of Dihydro-C14-Aldehyde was calculated from the individual solubilities in n-octanol and in water,
respectively, to be > 5.9
Executive summary:

Neither the HPLC-method according to OECD Guideline No. 117 nor the flask-shaking method according to OECD Guideline No. 107 were applicable for the determination of the partition coefficient of Dihydro-C14-Aldehyde. Thus, the log POW-value for the test item was estimated from its solubility in n-octanol and in water, respectively. In the present study, the n-octanol solubility of Dihydro-C14-Aldehyde was determined to be > 526.5 g/l. After the incubation time, the test item was completely dissolved by visual judgement. A typical chromatogram of a standard solution is given in Figure 4. A typical chromatogram of a sample solution in n-octanol is given in Figure 5. The calibration data for test item-standards are given in Table 4. The correlation coefficient r² fit was 0.9998 (optimum = 1.0000). This reflects the linearity of the GC-system within the calibration range of 0.325 µg/ml to 8.118 µg/ml of the test item. The calibration curve is shown in Figure 6. The tabulated values represent rounded results, which were obtained by calculation using the exact raw data. In conclusion, the partition coefficient, log Pow, of Dihydro-C14-Aldehyde was calculated from the individual solubilities in n-octanol and in water, respectively, to be >5,9.