Phenylacetic acid

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Experimental test result performed using standard test guidelines

Qualifier:

according to guideline

Guideline:

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

Principles of method if other than guideline:

The partition Coefficient n-octanol/water of test chemical was determined by the Reverse Phase High Performance Liquid Chromatographic method according to OECD Guideline No. 117.

GLP compliance:

no

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

Key result

Type:

log Pow

Partition coefficient:

0.811

Temp.:

25 °C

pH:

5.6

Remarks on result:

other: logKow was reported to be 0.811 ± 0.005

Details on results:

The Partition coefficient (Pow) of the test chemical was determined to be 0.811 ± 0.005 at 25°C.

Test substance		K	Log k	Log Pow by Generalized Calibration Graph	Mean of Log Pow ± S.D.
tR1	1.128	0.2	-0.698	0.815	0.811± 0.005
tR2	1.127	0.198	-0.701	0.808

Conclusions:

The partition coefficient(n-octanol/water) of test chemical was determined as per the HPLC method (OECD Guideline-117). The Log Pow value was determined to be 0.811 ± 0.005 at 25°C.

Executive summary:

The partition Coefficient n-octanol/water of test chemical was determined by the Reverse Phase High Performance Liquid Chromatographic method according to OECD Guideline No. 117 for testing of Chemicals. A test item solution was prepared by accurately weighing 4 mg of test item and diluted with ACN up to 10 ml. Thus, the test solution concentration was 400 mg/l. The pH of test substance was 5.6. The reference substances were chosen according to functional similarity with the test substance and calibration graph was prepared. The reference substances were Biphenyl, 4-Acetylpyridine, Dodecanoic acid, Toluene, Ethylbenzene, Naphthalene having Pow value ranging from 0.5 to 4.2. The Log Pow value was determined to be 0.811 ± 0.005 at 25°C. Based on this value, it can be concluded that test chemical is hydrophilic in nature.

Description of key information

Based on the available data from study report,the partition Coefficient n-octanol/water of test chemical was determined by the Reverse Phase High Performance Liquid Chromatographic method according to OECD Guideline No. 117 for testing of Chemicals. A test item solution was prepared by accurately weighing 4 mg of test item and diluted with ACN up to 10 ml. Thus, the test solution concentration was 400 mg/l. The pH of test substance was 5.6. The reference substances were chosen according to functional similarity with the test substance and calibration graph was prepared. The reference substances were Biphenyl, 4-Acetylpyridine, Dodecanoic acid, Toluene, Ethylbenzene, Naphthalene having Pow value ranging from 0.5 to 4.2. The Log Pow value was determined to be 0.811 ± 0.005 at 25°C. Based on this value, it can be concluded that test chemical is hydrophilic in nature.

Key value for chemical safety assessment

Log Kow (Log Pow):

0.811

at the temperature of:

25 °C

Additional information

Based on the available data in a key study from study report,the partition Coefficient n-octanol/water of test chemical was determined by the Reverse Phase High Performance Liquid Chromatographic method according to OECD Guideline No. 117 for testing of Chemicals. A test item solution was prepared by accurately weighing 4 mg of test item and diluted with ACN up to 10 ml. Thus, the test solution concentration was 400 mg/l. The pH of test substance was 5.6. The reference substances were chosen according to functional similarity with the test substance and calibration graph was prepared. The reference substances were Biphenyl, 4-Acetylpyridine, Dodecanoic acid, Toluene, Ethylbenzene, Naphthalene having Pow value ranging from 0.5 to 4.2. The Log Pow value was determined to be 0.811 ± 0.005 at 25°C.

In a supporting study frompeer reviewed journal, authoritative database and secondary source,the octanol water partition coefficient of the test chemical was determined using the shake-flask method. In shake-flask method, a small amount of the solute is dissolved in either aqueous or organic phase, equilibrium partition is obtained by agitation, the phases are separated and one or both phases are analyzed for solute. Several different methods of agitation are used to the solvents into intimate contact. The phases separate under normal gravity they are usually centrifuged to accelerate the separated the smallest droplets. Analytical method involve the use of absorption spectrophotometry for the measurement of partition coefficient. The solid support is usually silanized diatomaceous silica. The column is loaded by pulling an unsaturated solution of the solute of interest at a known concentration onto a water-saturated octanol through the column. The solute eluted with octanol-saturated water, and the effluent is analyzed by high pressure liquid chromatography or gas liquid chromatography. The partition coefficient (log Pow) value of the test chemical was determined to be 1.41 at a temperature of 25°C, respectively.

Additional study from peer reviewed journal, handbook, authoritative and modelling databases indicates that the octanol water partition coefficient (log Pow) value of the test chemical was determined to be 1.41.

Thus, based on the available information, the logPow value of the test chemical ranges from 0.811 to 1.41, respectively. On the basis of this value, test chemical can be considered to be hydrophilic in nature.