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Vapour pressure

Link to relevant study record(s)

Reference

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2019-02-01 to 2019-02-14

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:

adopted 2006

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method A.4 (Vapour Pressure)

Version / remarks:

European Commission Regulations (EC) No.440/2008 and No. 761/2009

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

effusion method: Knudsen cell

Key result

Test no.:

#1

Temp.:

<= 61 °C

Vapour pressure:

< 0.001 Pa

Remarks on result:

other: 10E-3 Pa was the method detection limit

The vapour pressure was measured in the temperature range of 20 °C to 71 °C. The measured vapour pressures at the corresponding temperatures are listed in the following table:

Temperature / °C	Vapour pressure / hPa
20	1.5 × 10^-4
31	1.9 × 10^-4
41	2.2 × 10^-4
51	1.8 × 10^-4
61	1.1 × 10^-4
71	6.5 × 10^-5
50	n.e.*
20	n.e.*
31	5.7 × 10^-6*
41	7.0 × 10^-6*
51	n.e.*
61	n.e.*
71	1.5 × 10^-5
50	n.e.*

n.e.: not evaluable

*: below the detection limit of 10^-5 hPa

The measurement was repeated with the same sample due to its unusual course in its first run (see also attached Figure). After the first run of the measurement a mass loss of approx. 3 % (w/w) was determined. After the second run of the measurement no significant mass loss was determined. It was assumed that the test item only lost volatile minor constituents or residual solvents during the first run (this would be in accordance to the certificate of analysis stating a loss on drying of 5 %). The second run did not yield sufficient data points for a regression. Therefore it can only be stated that the vapour pressure up to 61 °C was below 1 × 10 ^-5 hPa.

Conclusions:

Vapour pressure (OECD 104): < 1E-5 hPa at <= 61 °C

Executive summary:

The vapour pressure ot the test item was determined in a reliable and valid study performed compliant with GLP according to OECD 104 as well as EU method A.4. (Vapour pressure: effusion method). The method was chosen due to its high sensitivity and the fact that test item is a solid with no melting point.

The vapour pressure was measured in the temperature range of 20 °C to 71 °C. A vapour pressure above the method detection limit (10E-5 hPa; LOD) could only be measured at the highest temperature of 71 °C (1.5E-5 hPa). At the next lower temperature (61 °C), vapour pressure was below the LOD.

Final result:

The vapour pressure of the test item up to 61 °C was below 1 × 10^-5 hPa.

Description of key information

Vapour pressure (OECD 104): < 1E-5 hPa at <= 61 °C

Key value for chemical safety assessment

Vapour pressure:

0.002 Pa

at the temperature of:

71 °C

Additional information

The vapour pressure ot the test item was determined in a reliable and valid study performed compliant with GLP according to OECD 104 as well as EU method A.4. (Vapour pressure: effusion method). The method was chosen due to its high sensitivity and the fact that test item is a solid with no melting point.

The vapour pressure was measured in the temperature range of 20 °C to 71 °C. A vapour pressure above the method detection limit (10E-5 hPa; LOD) could only be measured at the highest temperature of 71 °C (1.5E-5 hPa). At the next lower temperature (61 °C), vapour pressure was below the LOD.

Final result: The vapour pressure of the test item up to 61 °C was below 1 × 10^-5 hPa.