Registration Dossier

Administrative data

Endpoint:
vapour pressure
Type of information:
experimental study
Adequacy of study:
key study
Study period:
2009
Reliability:
1 (reliable without restriction)

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2009

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 104 (Vapour Pressure Curve)
Qualifier:
according to
Guideline:
EU Method A.4 (Vapour Pressure)
GLP compliance:
yes (incl. certificate)
Type of method:
gas saturation method

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
Test article identification : Amorphophallus Campanulatus Dry Purified Extract
Batch number : 29895/M1
Chemical class : Botanical extract
Preparation date : April 2009
Expiry date : April 2011

The sample was stored at room temperature in the dark.

Results and discussion

Vapour pressureopen allclose all
Temp.:
25 °C
Vapour pressure:
0 Pa
Temp.:
20 °C
Vapour pressure:
0.009

Any other information on results incl. tables

Linear calibration

The data and results are summarized in Table 1.

They were used to perform a linear calibration used to quantify the test article in the aqueous test solutions coming from the sampling traps.

TABLE 1 Linear calibration with working standard solutions

Standard 1

5mg/mL

(Abs 220 nm)

Standard 2

15mg/mL

(Abs 220 nm)

Standard 3

25mg/mL

(Abs 220 nm)

Standard 4

50mg/mL

(Abs 220 nm)

Standard 5

100mg/mL

(Abs 220 nm)

1st

0.00499

0.01562

0.02360

0.04246

0.08476

2nd

0.00403

0.01478

0.02338

0.04163

0.08412

3rd

0.00373

0.01479

0.02306

0.04159

0.08398

Mean

0.00425

0.01507

0.02335

0.04189

0.08429

Parameterm

(slope)

0.00083

Parameterq

(intercept)

0.00153

ParameterR

(correlation)

0.99929

Vapour pressure

The vapour pressure tests were performed on the test article sample at 32°C (305 K) and at 40°C (313 K) with a 20 mL/min nitrogen flow rate.

Test at 305 K (32°C)

91.2 L of N2 at 20 mL/min

Volume of the trap solution: 28 mL

Abs 270 nm of the trap solution: 0.00851

Test article concentration of the trap solution calculated from linear calibration: 8.44mg/mL

                                                                10-6mg/g     62.41

P (mmHg) = 8.44mg/mL x 28 mL x ______________ x __________ x 305 K

                                                               400 g/mol           91.2 L

P (mPa) = P (mmHg) x 0.132 x 106 = 16.28 mPa            log P = 1.2115


Test at 313 K (40°C)

172.8 L of N2 at 20 mL/min

Volume of the trap solution: 23 mL

Abs 270 nm of the trap solution: 0.02383

Test article concentration of the trap solution calculated from linear calibration: 26.98mg/mL

                                                                    10-6mg/g                 62.41

P (mmHg) = 26.98mg/mL x 23 mL x ______________ x __________ x 313 K

                                                                  400 g/mol              172.8 L

P (mPa) = P (mmHg) x 0.132 x 106 = 23.15 mPa            log P = 1.3646

The vapour pressure value at lower temperatures can be calculated from the Clausius - Clapeyron equation:

                                             DHv

                      log P = _____________ + constant

                                             2.3 RT

where:

P        =           Pressure (Pa)

DHv    =           Heat of vaporization (J*mol-1)

T         =           Temperature (K)

R        =           Constant of gas (8.314 J*mol-1*K-1)

Reporting log P versus 1/T and extrapolating the values of the linear curve obtained, the vapour pressure values at 20 and 25°C are:

25°C (298 K)           1/T = 0.00336           Þ           log P = 1.0709           P = 11.8 mPa

20°C (293 K)           1/T = 0.00341           Þ           log P = 0.9663           P = 9.3 mPa

Since the results of the test carried out at 40°C show that the vapour pressure of the test article is below the recommended range defined in the quality criteria of the gas saturation method (10-4Pa to 1 Pa), additional tests were not performed at higher temperatures.

Applicant's summary and conclusion

Conclusions:
From the experimental data obtained it can be concluded that the vapour pressure of the sample of Amorphophallus Campanulatus Dry Purified Extract is:

P = 11.8 mPa = 1.18 x 10 -2 Pa = 8.92 x 10 -5 mmHg at 25°C
P = 9.3 mPa = 0.93 x 10 -2 Pa = 7.01 x 10 -5 mmHg at 20°C