Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Physical & Chemical properties

Vapour pressure

Currently viewing:

Administrative data

Link to relevant study record(s)

Reference
Endpoint:
vapour pressure
Type of information:
(Q)SAR
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: The vapour pressure of the natural complex substances was calculated from the vapour pressures of the known constituents estimated by the QSAR Mpbpwin v.143.
Justification for type of information:
QSAR prediction
Reason / purpose for cross-reference:
reference to same study
Qualifier:
no guideline followed
Principles of method if other than guideline:
This parameter varies as the composition of the mixture changes during evaporation. For Type 1 NCSs with known constituents the “initial” vapour pressure can be calculated as the sum of the partial pressure of the known constituents. Also a range of the vapour pressure can be given. Therefore, the first approach will be a calculation of the vapour pressure based on constituents. Figure (attached as picture) shows that the measured values are very similar to the estimated values for various citrus oil constituents. Only for constituents with low measured vapour pressure, the estimation method overestimates the vapour pressure. However, it is considered that these extreme non-volatile constituents (<1 Pa) are not relevant for the volatility of the NCS. It is recommended in the NCS protocol to calculate the initial vapour pressure based on the vapour pressures of the individual constituents. From the comparison between estimated and measured data in the figure, it can be concluded that the epiwin calculation method can be considered as reliable. Therefore, the epiwin estimation method is considered as relevant to estimate vapour pressures for this group of constituents. For the initial vapour pressure, the estimated values are used in the calculation. The “initial” vapour pressure is calculated as the sum of the partial pressure of the constituents (based on molecular fraction).
GLP compliance:
no
Type of method:
other: Calculation by estimation
Key result
Temp.:
25 °C
Vapour pressure:
170.9 Pa
Remarks on result:
other: Initial vapour pressure

Substance CAS Fraction Estimated vapour pressure (Pa at 25 degrees Celsius) Molecular weight
D-limonene 5989-27-5 0.440 193 136.24
γ-terpinene 99-85-4 0.100 153 136.24
Citral 5392-40-5 0.030 12.2 152.24
Terpinolene 586-62-9 0.060 133 136.24
Beta-Pinene 127-91-3 0.100 334 136.24
Neryl Acetate 141-12-8 0.010 6.17 196.29
Myrcine B 123-35-3 0.010 320 136.24
Alpha-Terpineol 98-55-5 0.070 2.62 154.25
5-Geranoxy-7-methoxycoumarin 7380-39-4 0.020 0.0000026 328.41
Alpha-Bergamotene 13474-59-4 0.010 3.69 204.36
Alpha-Terpinene 99-86-5 0.010 222 136.24
Beta-Bisabolene 495-61-4 0.010 2.93 204.36
Farnesene 4602-84-0 0.010 0.00525 222.37
Para-Cymene 99-87-6 0.010 152 134.22
1,4-cineole 470-67-7  0.040 238 154.25
alpha-pinene 7785-70-8 0.020 536 136.24
Sabinene 3387-41-5 0.010 981 136.24
Furocoumarins N/A 0.030 N/A N/A

Weight percentages of constituents are converted to molar percentages using the molecular weight (MW).

The sum of the vapour pressures multiplied by the fractions in the mixture is 169.15 Pa. To correct for the 4% unknown constituents (assuming the average vapour pressure for the unknown constituents is similar to tha average vapour pressure of the known constituents), this number is multiplied by 1 / 0.99.

Conclusions:
The initial vapour pressure of lime oil is 170.9 Pa at 25 degrees Celsius.
Executive summary:

The initial vapour pressure of lime oil was estimated by calculation. Vapour pressures for the known constituents were estimated using the QSAR MPBPWIN v 1.43. The sum of the vapour pressures multiplied by the molecular fraction of the substance in the NCS was taken as an initial estimate for the vapour pressure of the mixture. The number obtained was then corrected for the unknown constituents (assuming the average vapour pressure for the unknown constituents is similar to the average vapour pressure of the known constituents).

The initial vapour pressure of lime oil was found to be 170.9 Pa at 25 degrees Celsius. The vapour pressure of the constituents ranges from 2.6 x 10^-6 to 981 Pa.

Description of key information

Initial Vapour pressure: 170.9 Pa at 25 degrees Celsius

Key value for chemical safety assessment

Vapour pressure:
170.9 Pa
at the temperature of:
25 °C

Additional information

In a key study, the vapour pressure of lime oil was calculated using estimates of the vapour pressures of its' constituents, in line with the NCS protocol. The initial vapour pressure of lime oil was found to be 170.9 Pa at 25 degrees Celsius. The vapour pressure for the constituents ranges from 2.6.10^-6 to 981 Pa.