Isonicotinaldehyde

Partition coefficient

Administrative data

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

5 February - 9 April 2003

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP - guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2003

Report date:

2003

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EU Method A.8 (Partition Coefficient)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 117 (Partition Coefficient (n-octanol / water), HPLC Method)

Deviations:

no

GLP compliance:

yes

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Test material

Test material information

Constituent 1

Reference substance name:

Isonicotinaldehyde

EC Number:

212-832-3

EC Name:

Isonicotinaldehyde

Cas Number:

872-85-5

Molecular formula:

C6H5NO

IUPAC Name:

pyridine-4-carbaldehyde

Test material form:

other: liquid

Details on test material:

- Name of test material (as cited in study report) : Pyridine-4-aldehyde
- Physical state : clear yellowish liquid
- Analytical purity : 98,7% (GC)
- Lot/batch No. : 1120126/001
- Storage condition of test material : Refrigerator at ca. 4°C , in the dark , under nitrogen

Study design

Analytical method:

high-performance liquid chromatography

Results and discussion

Partition coefficient

Type:

log Pow

Partition coefficient:

0.12

Temp.:

30 °C

pH:

7

Applicant's summary and conclusion

Conclusions:

log Pow : 0.12
The study was performed according to the EU method A.8 without deviations and therefore considered to be of the highest quality (reliability Klimisch 1).The validity criteria are fulfilled.

Executive summary:

The partition coefficient of the test material was determined according to Method A8, whereby the concentration of the test material in the sample solutions was determined by high performance liquid chromatography (HPLC). The preliminary octanol-water partition coefficient was estimated by an Atom/Fragment Contribution Method using the software KOWWIN© Version v1.66 (Syracuse Research Corporation, New York, USA). The estimated preliminary decadic logarithm log Pow of Pyridine-4 -aldehyde is 0.5. According to the guideline the shake flask method is applicable when the log Pow value falls within the range of -2 to 4 and the HPLC method within the range 0 to 6. The shake flask method applies only to essentially pure substances soluble in water and n-octanol. For this test substance the HPLC-method was chosen for the main test. According to the guidelines this test method should not be applied to ionizable compounds without applying a correction. The use of buffer solutions in place of water should be considered for such compounds, the pH of the buffer should be at least 1 pH unit apart from the pKa of the substance and bearing in mind the relevance of this pH for the environment. The test substance contains basics as well as acid groups : The dissociation constants are 4,8 (nitrogen) and 12,2 (aldehyde), according to the SPARC pKa database (reference is IUPAC/Perrin 1150) and 4,77 to the Syracuse PhysProp database (reference is Perrin 1965). The undissociated form is therefore present at pH-values 6 and 11, and the mobile phase was buffered to pH 7 in the main Test. The temperature during the test was 30°C.

The decadic logarithm of the partition coefficient (log Pow) of "PYRIDINE-4-ALDEHYDE" is 0.12.