Elemol-rich fraction of essential oil of Canarium commune (Burseraceae) obtained from exudate by fractional distillation

Vapour pressure

Link to relevant study record(s)

Reference

Endpoint:

vapour pressure

Type of information:

(Q)SAR

Adequacy of study:

key study

Study period:

15-27 March 2018

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Justification for type of information:

1. SOFTWARE
iSafeRat® HA-QSAR toolbox v1.1

2. MODEL (incl. version number)
iSafeRat® HA-QSAR v 1.3 to predict Vapour Pressure

3. SMILES OR OTHER IDENTIFIERS USED AS INPUT FOR THE MODEL
SMILES code (see attached QPRF)

4. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL
See attached QMRF

5. APPLICABILITY DOMAIN
See attached QPRF

6. ADEQUACY OF THE RESULT
See attached QPRF

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 104 (Vapour Pressure Curve)

Deviations:

yes

Remarks:

QSAR model

Principles of method if other than guideline:

A Quantitative Structure-Property Relationship (QSPR) model was used to calculate the vapour pressure of the constituents of the test item. This QSPR model has been validated as a QSAR model to be compliant with the OECD recommendations for QSAR modeling (OECD, 2004) and predicts the endpoint value which would be expected when testing the substance under experimental conditions in a laboratory following Guideline for Testing of Chemicals No. 104, "Vapour Pressure". The criterion predicted was the vapour pressure at 25°C in Pascals.

The determination was performed using a regression method in which validated boiling point values are plotted against the log of vapour pressure values, where the pressure is in Pascals. The comparison was made with other members of the same chemical group. The results are considered to be as accurate as those from a good quality OECD guideline 104 study.

GLP compliance:

no

Type of method:

other: QSAR

Key result

Temp.:

25 °C

Vapour pressure:

0.505 Pa

Remarks on result:

other: constituent 1

Key result

Temp.:

25 °C

Vapour pressure:

1.8 Pa

Remarks on result:

other: constituent 2

Key result

Temp.:

25 °C

Vapour pressure:

239 Pa

Remarks on result:

other: constituent 3

Key result

Temp.:

25 °C

Vapour pressure:

7.58 Pa

Remarks on result:

other: constituent 4

Key result

Temp.:

25 °C

Vapour pressure:

286 Pa

Remarks on result:

other: constituent 5

Key result

Temp.:

25 °C

Vapour pressure:

0.288 Pa

Remarks on result:

other: constituent 6

Key result

Temp.:

25 °C

Vapour pressure:

5.7 Pa

Remarks on result:

other: constituent 7

Key result

Temp.:

25 °C

Vapour pressure:

12.7 Pa

Remarks on result:

other: constituent 8

Key result

Temp.:

25 °C

Vapour pressure:

229 Pa

Remarks on result:

other: constituent 9

Key result

Temp.:

25 °C

Vapour pressure:

0.231 Pa

Remarks on result:

other: constituent 10

Key result

Temp.:

25 °C

Vapour pressure:

0.167 Pa

Remarks on result:

other: constituent 11

Key result

Temp.:

25 °C

Vapour pressure:

22.1 Pa

Remarks on result:

other: constituent 12

Key result

Temp.:

25 °C

Vapour pressure:

0.199 Pa

Remarks on result:

other: constituent 13

Key result

Temp.:

25 °C

Vapour pressure:

160 Pa

Remarks on result:

other: constituent 14

Key result

Temp.:

25 °C

Vapour pressure:

372 Pa

Remarks on result:

other: constituent 15

The results below are the vapour pressure values of 15 constituents of the substance (covering more than 85% of the composition), which can be anticipated during a study following the OECD Guideline No. 104. The vapour pressure values are calculated as follows:

constituents	vapour pressure (Pa) at 25 °C	95% confidence limits (Pa)
Constituent 1	0.505	0.405 - 0.629
Constituent 2	1.80	1.67 - 1.95
Constituent 3	239	227 - 252
Constituent 4	7.58	6.08 - 9.45
Constituent 5	286	272 - 302
Constituent 6	0.288	0.231 - 0.359
Constituent 7	5.70	5.27 - 6.17
Constituent 8	12.7	10.1 - 15.8
Constituent 9	229	217 - 241
Constituent 10	0.231	0.185 - 0.288
Constituent 11	0.167	0.134 - 0.208
Constituent 12	22.1	21.0 - 23.3
Constituent 13	0.199	0.159 - 0.248
Constituent 14	160	152 - 169
Constituent 15	372	352 - 392

Conclusions:

The vapour pressures of 15 constituents of the test item were estimated based on a valid QSAR as follows:

Constituents : vapour pressure (Pa) at 25 °C (95% confidence limits (Pa))
Constituent 1 : 0.505 Pa (0.405-0.629 Pa)
Constituent 2 : 1.80 Pa (1.67-1.95 Pa)
Constituent 3 : 239 Pa (227-252 Pa)
Constituent 4 : 7.58 Pa (6.08-9.45 Pa)
Constituent 5 : 286 Pa (272-302 Pa)
Constituent 6 : 0.288 Pa (0.231-0.359 Pa)
Constituent 7 : 5.70 Pa (5.27-6.17 Pa)
Constituent 8 : 12.7 Pa (10.1-15.8 Pa)
Constituent 9 : 229 Pa (217-241 Pa)
Constituent 10 : 0.231 Pa (0.185-0.288 Pa)
Constituent 11 : 0.167 Pa (0.134-0.208 Pa)
Constituent 12 : 22.1 Pa (21.0-23.3 Pa)
Constituent 13 : 0.199 Pa (0.159-0.248 Pa)
Constituent 14 : 160 Pa (152 - 169 Pa)
Constituent 15 : 372 Pa (352 - 392 Pa)

Executive summary:

A calculation method prediction was performed to assess the vapour pressure of 15 constituents of the substance. This calculation method predicts the endpoint value which would be expected when testing a pure substance under experimental conditions in a laboratory following Guideline for Testing of Chemicals No. 104.

The estimation method is based on a linear regression equations for a series of common structures (for example alkanes) generated using high quality vapour pressure data. In the majority of cases data for vapour pressure were obtained from the following methods described in the OECD Guideline No. 104: isoteniscope, dynamic, static, effusion (vapour pressure balance or loss of weight) and gas saturation methods. Likewise, data for boiling points were obtained from the following methods described in the OECD Guideline No. 103: DSC (Differential Scanning Calorimetry), DTA (Differential Thermal Analysis), dynamic method, capillary (Siwoloboff) method, ebulliometer, distillation and photocell detection.

Finally the vapour pressures of 15 constituents of the test item (covering more than 85% of the composition) were estimated in a range between 0.167 and 372 Pa at 25°C.

Description of key information

The vapour pressure of the constituents of the substance (15 components of the substance covering more than 85% of the composition) are in the range between 0.167 and 372 Pa at 25°C (valid QSAR estimations).

Additional information

No study was conducted on the test item itself.

The test item is a natural complex substance (NCS). It is a mixture of several constituents, but 15 of them represent more than 85% of that mixture.

A valid calculation method (QSAR approach) has been used to estimate the vapour pressure of these constituents at 25°C. It predicts the endpoint value which would be expected when testing pure substances under experimental conditions in a laboratory following Guideline for Testing of Chemicals No. 104.

The vapour pressure of the constituents of the substance were estimated at 25°C as follows:

constituents	vapour pressure (Pa) at 25 °C	95% confidence limits (Pa)
Constituent 1	0.505	0.405 - 0.629
Constituent 2	1.80	1.67 - 1.95
Constituent 3	239	227 - 252
Constituent 4	7.58	6.08 - 9.45
Constituent 5	286	272 - 302
Constituent 6	0.288	0.231 - 0.359
Constituent 7	5.70	5.27 - 6.17
Constituent 8	12.7	10.1 - 15.8
Constituent 9	229	217 - 241
Constituent 10	0.231	0.185 - 0.288
Constituent 11	0.167	0.134 - 0.208
Constituent 12	22.1	21.0 - 23.3
Constituent 13	0.199	0.159 - 0.248
Constituent 14	160	152 - 169
Constituent 15	372	352 - 392

The substance is an UVCB with constituents having different vapour pressures. In addition we can not anticipate the impact of the interactions between the constituents and the influence of the physical state of the substance on the whole substance vapour pressure.

Therefore we considered the vapour pressure of the 15 constituents of the substance and no single key value was retained (nor calculated weighted Vapour pressure nor worst-case).