Reaction mass of 1-(2,6,6-trimethyl-1-cyclohexen-1-yl)pent-1-en-3-one and 1-(2,6,6-trimethyl-2-cyclohexen-1-yl)pent-1-en-3-one

Partition coefficient

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

from July 17, 2006 to August 28, 2006

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

1989

Qualifier:

according to guideline

Guideline:

EU Method A.8 (Partition Coefficient - HPLC Method)

GLP compliance:

yes (incl. QA statement)

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

Key result

Type:

log Pow

Partition coefficient:

4.7

Temp.:

35 °C

Remarks on result:

other: peak 1 at retention time 11.565

Type:

log Pow

Partition coefficient:

4.9

Temp.:

35 °C

Remarks on result:

other: peak 2 at retention time 12.351

Details on results:

The determination was performed at 35°C (temperature of the column), but the value obtained can be considered to represent the value at an unspecified, probably ambient temperature since no mention is made in the guidelines of the temperature at which the tabulated reference substances log Pow values were determined. Partition coefficients of the test and reference substances are assumed to vary with temparature in the same way.

Conclusions:

The chromatogram shows two peaks at retention times 11.565 and 12.351 minutes, that can be assigned to the n-alpha and n-beta isomers respectively and correspond to partition coefficients (log value) of 4.7 and 4.9.
Therefore:
Partition coefficients n-octanol/water of RALDEINE A:
n-alpha isomer log Pow = 4.7
n-beta isomer log Pow = 4.9
The partition coefficient estimated with KOWWIN software is 4.78. This is in relative good agreement with the experimental value.

Executive summary:

The partition coefficient n-octanol/water of RALDEINE A was determined by the Reverse Phase High Performance Liquid Chromatographic Method according to the OECD guidelines for testing of chemicals, Method no. 117.

The result is:

Partition coefficients n-octanol/water of RALDEINE A:

n-alpha isomer log Pow = 4.7

n-beta isomer log Pow = 4.9 .

Reference 2

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

20-September-2017

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The information is derived from a reliable non-GLP in-house study according to OECD TG 117 (HPLC).

Qualifier:

equivalent or similar to guideline

Guideline:

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

GLP compliance:

no

Type of method:

HPLC method

Partition coefficient type:

octanol-water

Key result

Type:

log Pow

Partition coefficient:

>= 4.7 - <= 4.9

Temp.:

25 °C

Remarks on result:

other: pH not provided in the study report

Details on results:

The pH is assessed not to be critical based on the absence of acidic and basic structural features of Methyl Ionone Alpha Extra and in its molecular structure.

Conclusions:

The partition coefficient has been determined as log P = 4.7-4.9 at 25°C in a study equivalent to OECD Guideline 117 (HPLC method) in a reliable non-GLP study.

Executive summary:

The partition coefficient has been determined as log P = 4.7-4.9 at 25°C in a study equivalent to OECD Guideline 117 (HPLC Method).

Description of key information

In the key study, the partition coefficient n-octanol/water of RALDEINE A was determined by the Reverse Phase High Performance Liquid Chromatographic Method according to the OECD guidelines for testing of chemicals, Method no. 117.

The result is:

Partition coefficients n-octanol/water of RALDEINE A:

n-alpha isomer log Pow = 4.7

n-beta isomer log Pow = 4.9

Since the major isomer in the registration substance is the n-alpha isomer, the log Kow value of 4.7 has been chosen as the key value for the purpose of the environmental exposure assessment.

Key value for chemical safety assessment

Log Kow (Log Pow):

4.7

at the temperature of:

35 °C

Additional information

The partition coefficient has been determined on two commercial qualities of the registration substance; Raldeine A (Key study, Givaudan 2006) and Methyl Ionone Alpha Extra (Supporting study, IFF 2017). Both determinations were performed using the HPLC method (OECD Guideline 117 or equivalent) and give similar results.

The key study (Givaudan 2006) was performed according to OECD Guideline 117, under GLP. The HPLC chromatogram showed 2 peaks that were assigned to the n-alpha isomer and n-beta isomer. The determined partition coefficients (log value) were 4.7 and 4.9 respectively. Since the major isomer in the registration substance is the n-alpha isomer, the log Kow value of 4.7 has been chosen as the key value for the purpose of the environmental exposure assessment. Both values are considered in the environmetal hazard classification and PBT assessment.

The determination was performed at 35°C (temperature of the column), but the value obtained can be considered to represent the value at an unspecified, probably ambient temperature since no mention is made in the guidelines of the temperature at which the tabulated reference substances log Pow values were determined. Partition coefficients of the test and reference substances are assumed to vary with temparature in the same way.

In the supporting study (IFF, 2017), the partition coefficient was determined as log P = 4.7-4.9 at 25°C in a reliable non-GLP study equivalent to OECD Guideline 117 (HPLC method).