Balmywood

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:

March, 23 - Avril, 06 2022

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, with no deviation, and under GLP. The test substance is adequately characterised. Therefore full validation applies.

Qualifier:

according to guideline

Guideline:

OECD Guideline 102 (Melting point / Melting Range)

Version / remarks:

27 July 1995

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.1 (Melting / Freezing Temperature)

Version / remarks:

Commission Regulation (EC) No 440/2008

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

GIPC GLP compliance (inspected on 18 -20 August 2020, signed on 17 Mars 2021)

Type of method:

differential scanning calorimetry

Melting / freezing pt.:

< -20 °C

Atm. press.:

98.6 kPa

First Determination

Mass taken: 10.72 mg
The beginning of melting range is not clearly identified as an exothermic peak (onset: -13.0°C) is observed before the endothermic peak corresponding to the melting of the test item. The end of melting range corresponds with the summit of the endothermic peak at 24.9°C.

Second Determination

Mass taken: 10.54 mg
As for the first determination, No significant peak that could corresponds with melting point/range of the substance was clearly identified down to -120°C. However, some disturbances were observed between about -20°C and 5°C and could correspond with melting and/or glass transition.

Additional Tests

- Measurement with successive cooling-heating cycles

Mass taken: 12.46 mg

The two heating phases obtained during the measurement have a similar profile between -20°C and 30°C. The onset and endset values slightly differs but the shape remains more or less the same. The observed variation is repeatable and could eventually correspond with glass transition and/or melting.

- Appearance of the test item

After seven hours left in a refrigerator at about 5°C, the test item remains liquid. After seven hours left in a freeze at about -26°C, the test item remains liquid even if the substance looks more viscous.

Therefore, the disturbances observed during the measurements between about -20°C and 5°C do not correspond with melting or glass transition.

Conclusions:

The melting point/range of the test item was determined to be lower than -20°C.

Executive summary:

The melting point of the test substance was determined under GLP according to OECD 102 / EU A1 guideline, using the DSC method.

Two main runs were performed.

No melting point/range of the substance was clearly identified down to -120°C. Some disturbance were observed between about -20°C and 5°C and could have correspond with melting and/or glass transition. Therefore, additional tests were performed. A temperature program including two successive cooling-heating cycles was carried out to check if the variation observed on the thermogram is repeatable. In addition, two samples of the test item were placed one in a refrigerator at about 5°C and the other in a freezer below -20°C for several hours and then checked for condition.

Considering the obtained results, the melting point/range of the test item was determined to be lower than -20°C.

Description of key information

The melting point/range of the test item was determined to be lower than -20°C.at 98.6 kPa.

Additional information

A fully reliable experimental study, conducted according to a recognized OECD/EC method and under GLP, is available. It is considered as key study. As the onset of melting could not be determined, and the test items appeared liquid at the limit temperature of -20°C, the result is expressed as a range, and cannot be retained as key data.