Boswellia papyrifera, ext.

Melting point / freezing point

Link to relevant study record(s)

Reference

Endpoint:

melting point/freezing point

Type of information:

experimental study

Adequacy of study:

key study

Study period:

October 25 - November 07, 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

The study was conducted according to an internationally recognised method, and under GLP. The substance is considered to be adequately characterised. Therefore full validation applies.

Qualifier:

according to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

Version / remarks:

dated 27. July 1995

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

Version / remarks:

dated 30. May 2008

Deviations:

no

Principles of method if other than guideline:

Not applicable

GLP compliance:

yes (incl. QA statement)

Remarks:

GLP compliance programme (inspected on 20-21 June 2017 / signed on 4 September 2017)

Type of method:

differential scanning calorimetry

Key result

Melting / freezing pt.:

< -20 °C

Individual results

Melting point / melting range: DSC measurement

Two DSC measurements in aluminium crucibles with a hole were performed. The crucibles were cooled to -80°C with a rate of 1 K/min and hold at this temperature for 5 h. Afterwards followed heating with a rate of 10 K/min. The measurements showed a endothermal in the temperature range of ‑70 – ‑40 °C, which was attributed to melting. The onset temperature was derived from the intersection of the tangent line with the highest slope of the endothermal peak with the baseline.

The results of the DSC measurements are summarized in table below.

Table 4.2 -1.-Melting point (DSC measurements)

Ident No.	Test item / mg	Starting temperature / °C	Final test temperature  / °C	Temperature range (endo-thermal)  / °C	Onset (melting) / °C	Crucible	Observations after the measurement
38312	12.01	-80	500	‑70 – ‑40	-52.0	Aluminium with a hole	The crucible was empty
38323	12.58	-80	500	‑70 – ‑40	-51.0	Aluminium with a hole	The crucible was empty

Graphical presentations of the DSC runs are shown on the experimental report.

The test item had a mean melting point of -51.5 °C.

Conclusions:

The freezing point of test item was stated as < - 20 °C (< 253.15 K).

Executive summary:

The freezing point of the test item was determined under GLP according to EU Method A.1 and OECD 102.

 

In a pre-test, the test item was still liquid at - 20 °C. According to Regulation (EC) No 1907/2006 (REACH) annex VII, column 2 of section 7.2, the determination of the melting / freezing point does not need to be conducted below a lower limit of - 20 °C. Therefore, no additional test was conducted and the freezing point is stated as < - 20 °C (< 253.15 K).

Description of key information

The freezing point was below - 20 °C (< 253.15 K)

Additional information

A fully reliable experimental study, conducted according to a recognized OECD/EC method and under GLP, is available. It is considered as a key study.