Rabitle FP-100

Partition coefficient

Link to relevant study record(s)

Reference

Endpoint:

partition coefficient

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Experimental start date: 30th January Experimental completion date: 16th May 2007 Study completion date: 12th June 2007

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: - Study generated according to generally valid and/or internationally accepted testing guidelines - Performed according to GLP - Test parameters based on specific testing guideline

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

OECD Guideline 107 (Partition Coefficient (n-octanol / water), Shake Flask Method)

Version / remarks:

92/69/EEC, A8 (HPLC Method)

Deviations:

yes

Remarks:

First Amendment to Study Plan: Concerning: Schedule Alteration: New experimental completion date Reason for the alteration: Delay in study

Qualifier:

according to guideline

Guideline:

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

Deviations:

yes

Remarks:

First Amendment to Study Plan: Concerning: Schedule Alteration: New experimental completion date Reason for the alteration: Delay in study

GLP compliance:

yes (incl. QA statement)

Type of method:

shake-flask method to: flask method

Remarks:

and HPLC method

Partition coefficient type:

octanol-water

Analytical method:

high-performance liquid chromatography

Type:

log Pow

Partition coefficient:

> 6.5

Temp.:

20 °C

pH:

ca. 4

Details on results:

During the preliminary test, the log Pow of FP-100 was estimated to be above 3.8. Therefore, the HPLC-method was chosen to conduct the main test. Six common standards, which have known log Pow values in the range of 0.3 to 6.5, were used as reference standards during the main test.

The FP-100 solution was injected three times and the combined reference solution was injected six times. The thiourea solution was injected twice.

According to the guideline, a minimum amount of 25% aqueous solution is required in the mobile phase for the log Pow determination. However, with an eluent (mobile phase) of water and acetonitrile (25:75, v/v) the test item FP-100 could not be eluted from the column after a run time of 25 minutes. The reference item with the highest log Pow eluted at a retention time of about 17 minutes. Thus, the log Pow of the test item is far above 6.5, which is the log Pow of the most lipophilic reference item 2,4-DDT. In order to demonstrate that the test item has been retained by the column, the eluent has been changed after 25 minutes to 100% acetonitrile, which is the most suitable solvent known for the test item (as given by a solubility test). After about 3.5 minutes with 100% acetonitrile a test item peak could be observed in the HPLC chromatogram. A second peak could be observed after about 5.5 minutes.

In conclusion, using the HPLC method, the n-octanol/water partition coefficient of FP-100 was determined to be
log Pow > 6.5.

Conclusions:

Using the HPLC method, the n-octanol/water partition coefficient of FP-100 was determined to be
log Pow > 6.5.

Executive summary:

Not Provided

Description of key information

During the preliminary test, the log Pow of FP-100 was estimated to be above 3.8. Therefore, the HPLC-method was chosen to conduct the main test. Six common standards, which have known log Pow values in the range of 0.3 to 6.5, were used as reference standards during the main test.
The FP-100 solution was injected three times and the combined reference solution was injected six times. The thiourea solution was injected twice.
According to the guideline, a minimum amount of 25% aqueous solution is required in the mobile phase for the log Pow determination. However, with an eluent (mobile phase) of water and acetonitrile (25:75, v/v) the test item FP-100 could not be eluted from the column after a run time of 25 minutes. The reference item with the highest log Pow eluted at a retention time of about 17 minutes. Thus, the log Pow of the test item is far above 6.5, which is the log Pow of the most lipophilic reference item 2,4-DDT. In order to demonstrate that the test item has been retained by the column, the eluent has been changed after 25 minutes to 100% acetonitrile, which is the most suitable solvent known for the test item (as given by a solubility test). After about 3.5 minutes with 100% acetonitrile a test item peak could be observed in the HPLC chromatogram. A second peak could be observed after about 5.5 minutes.
In conclusion, using the HPLC method, the n-octanol/water partition coefficient of FP-100 was determined to be
log Pow > 6.5.

Key value for chemical safety assessment

Log Kow (Log Pow):

6.5

at the temperature of:

20 °C

Additional information

During the preliminary test, the log Pow of FP-100 was estimated to be above 3.8. Therefore, the HPLC-method was chosen to conduct the main test. Six common standards, which have known log Pow values in the range of 0.3 to 6.5, were used as reference standards during the main test.

 

The FP-100 solution was injected three times and the combined reference solution was injected six times. The thiourea solution was injected twice.

 

According to the guideline, a minimum amount of 25% aqueous solution is required in the mobile phase for the log Pow determination. However, with an eluent (mobile phase) of water and acetonitrile (25:75, v/v) the test item FP-100 could not be eluted from the column after a run time of 25 minutes. The reference item with the highest log Pow eluted at a retention time of about 17 minutes. Thus, the log Pow of the test item is far above 6.5, which is the log Pow of the most lipophilic reference item 2,4-DDT. In order to demonstrate that the test item has been retained by the column, the eluent has been changed after 25 minutes to 100% acetonitrile, which is the most suitable solvent known for the test item (as given by a solubility test). After about 3.5 minutes with 100% acetonitrile a test item peak could be observed in the HPLC chromatogram. A second peak could be observed after about 5.5 minutes.

 

In conclusion, using the HPLC method, the n-octanol/water partition coefficient of FP-100 was determined to be

log Pow > 6.5.