Melaleuca alternifolia, ext.

Vapour pressure

Administrative data

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2007

Report date:

2007

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EU Method A.4 (Vapour Pressure)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

OECD Guideline 104 (Vapour Pressure Curve)

Deviations:

no

Test guideline 3

Qualifier:

according to guideline

Guideline:

EPA OPPTS 830.7950 (Vapor Pressure)

Deviations:

no

GLP compliance:

yes

Type of method:

static method

Test material

Test material information

Constituent 1

Reference substance name:

Melaleuca alternifolia, ext.

EC Number:

285-377-1

EC Name:

Melaleuca alternifolia, ext.

Cas Number:

85085-48-9

Molecular formula:

Not applicable (a generic molecular formula cannot be provided for this specific UVCB substance).

IUPAC Name:

Essential oil of melaleuca alternifolia

Test material form:

liquid

Specific details on test material used for the study:

- Purity: 100%
- Lot (batch) No.: 1215
- Expiration date of the lot: 30 March 2009
- Storage condition of test material: Room temperature, protected from light.

Results and discussion

Vapour pressure

Temp.:

25 °C

Vapour pressure:

2 100 Pa

Any other information on results incl. tables

A measured value of 2800 Pa at 25°C was obtained for the vapour pressure of the reference substance, propan-1-ol, in good agreement with the literature value of 2760 Pa (Handbook of Chemistry and Physics, CRC Press, 1977).

The full results for the two samples assessed are presented in Table 1 below:

Table 1. Vapour pressure results.

Measurement	Vapour Pressure (Pa)
	Run 1	Run 2
1	1800	2100
2	1600	2000
3	1600	1900
4	1500	1900
5	1400	1800
6	1400	1900

The two runs both show a decrease in the vapour pressure readings of the samples with time. This was considered to be due to the loss of the more volatile components during testing.

The decision was taken to report the maximum reading from both samples as the maximum vapour pressure of the test substance.

Applicant's summary and conclusion

Conclusions:

The maximum vapour pressure of Tea Tree Oil was determined to be 2100 Pa at 298K (25°C).

Executive summary:

A GLP-compliant study was carried out to determine the maximum vapour pressure of Tea Tree Oil. The study followed the requirements of EEC method A4, OECD method 104 and OPPTS method 830.7950 without significant deviation. The maximum vapour pressure of Tea Tree Oil was determined to be 2100 Pa at 298K (25°C).