Isotridecyl 3,5,5-trimethylhexanoate

Vapour pressure

Link to relevant study record(s)

Reference

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Study period:

12 April 2017 to 3 January 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 104 (Vapour Pressure Curve)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

effusion method: Knudsen cell

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%.

Key result

Temp.:

ca. 20 °C

Vapour pressure:

ca. 0.001 Pa

Remarks on result:

other: Extrapolated (see full table of results attached)

Key result

Temp.:

ca. 25 °C

Vapour pressure:

ca. 0.002 Pa

Remarks on result:

other: Extrapolated (see full table of results attached)

Key result

Transition / decomposition:

no

During the test, at some time between 11:30 and 13:15 on 5 July 2017 the cooling unit part of the test apparatus failed and the test temperature dropped from 25°C to 23°C. This deviation affected one timepoint only and this was subsequently repeated after the issue was rectified.

The vapour pressure of Isotridecyl 3,5,5-Trimethylhexanoate was found to be 0.0010 at 20°C and 0.0018 at 25°C. The full results are shown in Table 2 and the Ln VP vs 1/T plot shown in Figure 12.

The weight of the control crucible changed from 55.875 at beginning of test to 55.871 at end of test which is not considered significant.

There were no differences between the IR spectra for the untested, control and tested material; the comparative spectra are shown in Figure 13. Therefore the test substance was unchanged during the test.

Conclusions:

The vapour pressure of the test material was determined to be 0.001 Pa at 20 °C and 0.0018 at 25 °C under the conditions of the test.

Executive summary:

In this guideline (OECD 104) study, conducted with GLP certification, the vapour pressure of the test material was determined to be 0.001 Pa at 20 °C and 0.0018 at 25 °C under the conditions of the test.

Description of key information

Study conducted to recognised testing guidelines with GLP certification.

Key value for chemical safety assessment

Vapour pressure:

0.001 Pa

at the temperature of:

20 °C