Registration Dossier

Administrative data

Endpoint:
partition coefficient
Type of information:
experimental study
Adequacy of study:
key study
Study period:
September - October 2019
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2019
Report Date:
2019

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 117 (Partition Coefficient (n-octanol / water), HPLC Method)
Version / remarks:
April 13, 2004
Deviations:
yes
Remarks:
See note below
Principles of method if other than guideline:
The Test Item chemical structure indicated that it is neutral and it was run at neutral pH. OECD Test 117 states: Methanol/water ratios with a minimum water content of 25% should be used. The Test Item did not dissolve or chromatograph using a methanol:water 75:25 mobile phase but did chromatograph well when using a mobile phase with higher methanol content. The increased methanol content gave rise to a significant peak that could be used for OECD 117 calculations. The mobile phase used was methanol:water 88:12. The calibration standards were also run in this mobile phase. This is a minor deviation of the Method, but the calibration standards gave a good calibration curve so the deviation was acceptable.
GLP compliance:
not specified
Type of method:
HPLC method
Partition coefficient type:
octanol-water

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
impurity
Type:
impurity
Test material form:
liquid
Details on test material:
Common Name: BT4
Source Intertek Chemicals & Materials, Allentown
Purity: 85%
ID and percent known impurities: 2-ethylhexyl stearate (12%), 2-ethylhexyl palmitate (1%), 2-ethylhexyl esters of various C18 fatty acid impurities (~3%)
Date Received at Test Facility: September 5, 2019
Storage Instructions2 Ambient Temp
Specific details on test material used for the study:
Common Name: BT4
Source Intertek Chemicals & Materials, Allentown
Purity: 85%
ID and percent known impurities: 2-ethylhexyl stearate (12%), 2-ethylhexyl palmitate (1%), 2-ethylhexyl esters of various C18 fatty acid impurities (~3%)
Date Received at Test Facility: September 5, 2019
Storage Instructions2 Ambient Temp

Study design

Analytical method:
high-performance liquid chromatography

Results and discussion

Partition coefficient
Key result
Type:
log Pow
Partition coefficient:
> 7.6
Temp.:
24 °C
Remarks on result:
other: See remarks below
Details on results:
The log Pow could not be determined as because the retention time for the Test Item’s peak was out of the calibration range. In fact, the retention time of the Test Item (approximately 36 minutes) is very far from the last standard used for the test (6.5 minutes), which was oleic acid with a log Pow of 7.6, indicating a log Pow much greater than 7.6 for the Test Item. Therefore, the extrapolation method was not used to generate a log Pow value for the Test Item.

Applicant's summary and conclusion

Conclusions:
The Test Item, 2-ethylhexyl 12-(acetoxy)octadecanoate displayed a weighted average log Pow of greater than 7.6.
Executive summary:

BT4 was subjected to and OECD Guideline for the Testing of Chemicals. Test No. 117: Partition Coefficient (n-octanol/water), High Performance Liquid Chromatography (HPLC) Method

The Test Item was dissolved by dispensing 0.05 grams into vials containing 10 mL methanol. The solution was sonicated, resulting in partial dissolution, then syringe filtered through a 0.2 µm syringe filter to produce a clear solution that was run by HPLC. Two separate samples were prepared, and each was analyzed using HPLC. Methanol, treated as samples, was used as blank.

The log Powcould not be determined because the retention time for the Test Item’s peak was out of the calibration range. In fact, the retention time of the Test Item (approximately 36 minutes) is very far from the last standard used for the test (6.5 minutes), which was oleic acid with a log Powof 7.6, indicating a log Powmuch greater than 7.6 for the Test Item. Therefore, the extrapolation method was not used to generate a log Powvalue for the Test Item. A weighted average log Pow of greater than 7.6 is used.