Extract obtained from defatted powder of Theobroma cacao (Malvaceae) by extraction with ethanol

Vapour pressure

Link to relevant study record(s)

Reference

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Study period:

16 January 2018

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

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:

Commission Regulation (EC) No 761/2009 of 23. July 2009, published on 24. Aug. 2009

Deviations:

no

Principles of method if other than guideline:

Not applicable

GLP compliance:

yes (incl. QA statement)

Remarks:

GLP certificate (inspected on 15 to 16 November 2017 / signed on 15 May 2018)

Type of method:

static method

Key result

Temp.:

20 °C

Vapour pressure:

634 Pa

Key result

Temp.:

25 °C

Vapour pressure:

849 Pa

The calculation results are presented in the following table.

Table 4.6/1.- Calculated values for 1/T and log P

n	Temperature T	Pressure p	Temperature T	1/T	log p
	°C	hPa	K	1/K	log Pa
1	20.0	6.0	293.15	0.00341122	2.7782
2	29.2	11.6	302.35	0.00330743	3.0645
3	38.1	17.6	311.25	0.00321285	3.2455
4	47.4	29.2	320.55	0.00311964	3.4654
5	55.4	36.6	328.55	0.00304368	3.5635
6	48.2	30.4	321.35	0.00311187	3.4829
7	39.1	18.3	312.25	0.00320256	3.2625
8	30.3	12.2	303.45	0.00329544	3.0864
9	21.3	7.2	294.45	0.00339616	2.8573
10	16.3	4.6	289.45	0.00345483	2.6628

The parameters for the linear regression of the graph log (p) vs. 1/T are presented in the following table:

Table 4.6/2.-Linear Regression Parameters

Parameter	Value
Slope	-2216.107464
Intercept	10.36156339
Correlation coefficient r	-0.995350936
Coefficient of determination r^2	0.990723485

The coefficient of determination r² was calculated with 0.990723485. This value is above the threshold of 0.95.

The values of the heating and cooling down phase are within the recommended range for the static method (10^-2up to 10⁵Pa), according to the guideline and showed good correspondence.

Therefore, the result of the study is considered valid.

Using the equations below, vapour pressures at ambient temperature were calculated.

P(20 °C) = 10^{B * (1/293.15) + A} 

P(25 °C) = 10^{B * (1/298.15) + A}

Table 4.6/3.- Calculated Values for vapour pressure

Parameter	Value	Unit
Vapour Pressure (20 °C)	634	Pa
Vapour Pressure (25 °C)	849	Pa

Conclusions:

The vapor pressure of the test substance has been determined to be 634 Pa at 20 °C and 849 Pa at 25 °C (interpolation).

Executive summary:

The vapour pressure of the test substance was measured under GLP according to OECD 104 / EU A4 guideline using the static method.

10 individual measurements of vapour pressure were conducted in a temperature range of 16.3 – 55.4°C and the pairs of Temperature / Vapour pressure were used to calculate a regression from which vapour pressure at ambient temperature could be interpolated.

Finally, the vapor pressure of the test substance has been determined to be 634 Pa at 20 °C and 849 Pa at 25 °C.

 

Note that the result obtained on this kind of substance should be largely influence by small amounts of volatile constituents and these values probably don't represent the major part of the substance. Therefore the result should be considered with caution when used for subsequent assessment (worst case).

Description of key information

The vapor pressure of the test substance has been determined to be 634 Pa at 20 °C and 849 Pa at 25 °C (interpolation).

Key value for chemical safety assessment

Vapour pressure:

849 Pa

at the temperature of:

25 °C

Additional information

A reliable experimental study, conducted according to a recognized OECD/EC method and under GLP, is available. It is considered as a key study.

 

Note that the result obtained on this kind of substance should be largely influence by small amounts of volatile constituents and these values don't represent the major part of the substance. Therefore the result should be considered with caution when used for subsequent assessment (worst case).