Tobacco, ext.

Vapour pressure

Link to relevant study record(s)

Reference

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Testing was conducted between 17 October 2018 and 19 October 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 test substance is adequately characterised. Therefore full validation applies.

Qualifier:

according to guideline

Guideline:

OECD Guideline 104 (Vapour Pressure Curve)

Version / remarks:

2006

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.4 (Vapour Pressure)

Version / remarks:

2009

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Remarks:

Inspected on 4,5 and 6 July 2016/ Signed on 10 January 2017

Type of method:

static method

Key result

Temp.:

20 °C

Vapour pressure:

2 474 Pa

Key result

Temp.:

25 °C

Vapour pressure:

2 825 Pa

Results:

For each experimental temperature (T), log₁₀(p) was calculated from the mean of measured values. A vapour pressure curve was obtained by plotting log₁₀(p) against (1/T), with p in Pa and T in K.

A linear regression was obtained and the vapour pressure of the substance has been calculated at 20°C or 25°C.

Time (hh:mm)	Pressure (Pa)	Temperature (°C)
10:31	2270	20.1
11:36	2628	24.1
12:28	2959	28.1
13:38	3332	32.1
14:23	3708	36.1
15:19	3457	32.1
16:16	3197	28.1
17:33	2928	24.1
19:00	2650	20.1

Data exploitation

Vapour Pressure* (Pa)	Corresponding Temperature (°C)	Temperature (K)	1/T (K^-1)	Log10(p)
2460	20.1	293.25	3.410E-03	3.391
2778	24.1	297.25	3.364E-03	3.444
3078	28.1	301.25	3.320E-03	3.488
3395	32.1	305.25	3.276E-03	3.531
3708	36.1	309.25	3.234E-03	3.569

*: mean of pressures values for increasing and decreasing temperature if available.

 

A plot of Log₁₀(p) versus reciprocal temperature (1/T) (with p in Pa and T in K) gives the following statistical data using an unweighted least square treatment.

 

Slope              -1006.3

Intercept         6.8263

R²                   0.998

 

The results obtained indicate the following vapour pressure relationship:

 

Log₁₀(p (Pa)) = -1006.3 / T (K) +6.8263

 

The above equation yields a vapour pressure of 2474 Pa at 293.15 K and 2825 Pa at 298.15 K.

Conclusions:

The vapour pressure of the test substance is 2474 Pa at 20°C and 2825 Pa at 25°C.

Executive summary:

The vapour pressure of the test substance was measured under GLP according to OECD 104 / EU A4 guideline, static method. Temperature/vapour pressure were used to calculate a regression in a temperature range of 20.1 – 36.1 °C, from which vapour pressure at ambient temperature could be estimated.

From the measured values, the vapour pressure of the test item was calculated as 2474 Pa at 20.0 °C and 2825 Pa at 25 °C.

These values represent the component with the highest vapour pressure.

Description of key information

The vapour pressure of the test substance is 2474 Pa at 20°C and 2825 Pa at 25°C (interpolation).

These values represent the component with the highest vapour pressure (worst case).

Key value for chemical safety assessment

Vapour pressure:

2 825 Pa

at the temperature of:

25 °C

Additional information

A fully reliable experimental study, conducted according to a recognized OECD/EC method and under GLP, is available. Therefore, it is considered as a key study, and the result is retained as key data for purpose of CSA.