Isotridecyl 3,5,5-trimethylhexanoate

Hydrolysis

Administrative data

Endpoint:

hydrolysis

Type of information:

(Q)SAR

Adequacy of study:

supporting study

Study period:

12 April 2017 to 3 January 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

accepted calculation method

Justification for type of information:

Calculation
Due to the characteristics of the test substance, it was not possible to determine experimental values for the partition coefficient (log Pow) or the hydrolysis, in addition the water solubility was below the limit of quantification of the analytical method. It was decided that estimated values would be calculated for the partition coefficient and hydrolysis using appropriate software and as part of this procedure also produced estimated values for water solubility these have also been reported.
The full EPI Ver. 4.1 data are in the attachment.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2018

Report date:

2018

Materials and methods

Principles of method if other than guideline:

Calculation
Due to the characteristics of the test substance, it was not possible to determine experimental values for the partition coefficient (log Pow) or the hydrolysis, in addition the water solubility was below the limit of quantification of the analytical method. It was decided that estimated values would be calculated for the partition coefficient and hydrolysis using appropriate software and as part of this procedure also produced estimated values for water solubility these have also been reported.

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

1

Reference substance name:

Isotridecyl 3,5,5-trimethylhexanoate

EC Number:

261-675-7

EC Name:

Isotridecyl 3,5,5-trimethylhexanoate

Cas Number:

59231-37-7

Molecular formula:

C22H44O2

IUPAC Name:

isotridecyl 3,5,5-trimethylhexanoate

Test material form:

liquid

Specific details on test material used for the study:

The test substance, Isotridecyl 3,5,5-Trimethylhexanoate was allocated the code ESTS 67/17
for reference throughout the study.

Name: Isotridecyl 3,5,5-Trimethylhexanoate
CAS number: 59231-37-7
EC number: 261-675-7
Physical state: Clear colourless liquid
Sponsor lot number: P7639
Purity: Assumed to be 100%*
Molecular weight: 340.59
Arrival date: 1 March 2017
Expiry date: 1 December 2018
Storage conditions: Room temperature (15 to 30°C)

* No supporting information supplied.
Analytical Procedure
The procedure, SMV (PC) 3201859-01V, for determining the content of Isotridecyl 3,5,5Trimethylhexanoate in double-distilled water was developed in this study. The method used was Gas chromatography (GC) with flame ionisation detection (FID). A summary of the analytical procedure is shown in Appendix 2.
The method was assessed against the criteria detailed in the following sections:
Specificity
Blank solutions were prepared and run with the rest of the validation samples, to assess freedom from any interfering (co-chromatographic) peaks.
Sensitivity
The limit of quantification (LOQ) was described as the lowest fortification level where acceptable precision and accuracy data were obtained.
Linearity
The analytical calibration covered a range appropriate for the anticipated concentration of Isotridecyl 3,5,5-Trimethylhexanoate in double-distilled water. The linearity of detector response for standard solutions over the concentration range (minimum of five different concentrations) was determined by least squares linear regression with a 1/x weighting.
Accuracy and Precision (Repeatability)
For procedure SMV (PC) 3201859-01V, the accuracy and precision of the analysis was determined by analysis of five replicates of prepared sample solutions. The sample solutions were prepared at the following concentrations 1, 10 and 100 µg/mL by spiking into double-distilled water from a stock solution of Isotridecyl 3,5,5-Trimethylhexanoate in acetone. The solutions were super saturated with sodium chloride (0.4 g/mL) and then extracted with hexane, centrifuged a speed setting of 2500 rpm for 5 minutes and the hexane layer analysed. The volume of hexane chosen was such that the concentration was within the calibration line.
Acceptance criteria (SANCO/3029/99 rev. 4.) Accuracy (recovery)
The mean recovery values should be within 70 to 110% (ideally with the mean in the range 80 to 100%).
A suitable test for outliers may be applied to the accuracy data, for example the Grubbs or Dixons Tests.
Precision (repeatability)
The precision percent relative standard deviation (%RSD) should be ≤ 20%.

Study design

Analytical monitoring:

no

Results and discussion

Preliminary study:

Calculation
Due to the characteristics of the test substance, it was not possible to determine experimental values for the partition coefficient (log Pow) or the hydrolysis, in addition the water solubility was below the limit of quantification of the analytical method. It was decided that estimated values would be calculated for the partition coefficient and hydrolysis using appropriate software and as part of this procedure also produced estimated values for water solubility these have also been reported.

Transformation products:

not measured

Dissipation DT50 of parent compound

Key result

Remarks on result:

not determinable because of methodological limitations

Remarks:

Calculation Due to the characteristics of the test substance, it was not possible to determine experimental values for the partition coefficient (log Pow) or the hydrolysis, in addition the water solubility was below the limit of quantification of the analytical method. It was decided that estimated values would be calculated for the partition coefficient and hydrolysis using appropriate software and as part of this procedure also produced estimated values for water solubility these have also been reported.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

Calculated Values
The calculated hydrolysis values were a half-life T1/2 = 3.448 years (at pH 8) and T1/2 =
34.482 years (at pH 7).
The full EPI Ver. 4.1 data are shown inAppendix 3.

Executive summary:

Due to the low water solubility, which was below the limit of quantification of the analytical method, the partition coefficient could not be determined experimentally. Based on this it was decided that calculated partition coefficient values, using the Estimation Program Interface EPI ver. 4.1, would be reported instead.

Calculated Values

The calculated hydrolysis values were a half-life T1/2 = 3.448 years (at pH 8) and T1/2 =

34.482 years (at pH 7).

The full EPI Ver. 4.1 data are shown inAppendix 3.