5-fluoro-2-methoxypyrimidin-4(3H)-one

Vapour pressure

Link to relevant study record(s)

Reference

Endpoint:

vapour pressure

Type of information:

experimental study

Adequacy of study:

key study

Study period:

24 July 2005 to 03 August 2005

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method A.4 (Vapour Pressure)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Type of method:

effusion method: vapour pressure balance

Key result

Temp.:

25 °C

Vapour pressure:

< 0.001 Pa

Remarks on result:

other: Estimated vapour pressure value.

No statistical analyses were performed because the balance readings were too low and variable for a line of best fit to have any meaning. Instead it was considered more appropriate to impose a regression slope on a chosen data point to provide an estimate of the maximum value for the vapour pressure at 25 °C.

Run 5 was chosen because the sample had been under vacuum for the longest period prior to this run and so degassing would have been the most complete. The reading at 84 °C (357.15 K) was chosen because this is the data point which gives the highest estimated vapour pressure at any given temperature when a slope of-1500 K is imposed upon it.

The value of -1500 K is an in-house value and is the shallowest slope observed whilst determining the vapour pressure on a wide range of samples using the vapour pressure balance method. Extrapolation to 25 °C gave a vapour pressure of 6.656 x 10-4 Pa which has been taken a maximum for this material.

The test material did not change in appearance under the conditions used in the determination.

Conclusions:

Under the conditions of the test, the vapour pressure of the test material has been determined to be < 6.7 x 10^-4 Pa at 25 °C

Executive summary:

The vapour pressure of the test material was investigated in a study conducted via the standardised guideline EU method A.4 under GLP conditions.

The vapour pressure was determined using a vapour pressure balance with temperature and pressure readings were taken between 75 and 85 °C with a one hour dwell at 75 °C between runs. The sequence of runs was started after a sample of test material had been under vacuum for approximately 142 hours. Linear regression analysis was used to calculate the vapour pressure at 25 °C. Under the conditions of the test, the vapour pressure of the test material has been determined to be <6.7 x 10^-4 Pa at 25 °C.

Description of key information

Under the conditions of the test, the vapour pressure of the test material has been determined to be <6.7 x 10^-4 Pa at 25 °C.

Key value for chemical safety assessment

Vapour pressure:

0.001 Pa

at the temperature of:

25 °C

Additional information

The vapour pressure of the test material was investigated in a study conducted via the standardised guideline EU method A.4 under GLP conditions. The study was assigned a reliability score of 1 in accordance with the criteria for assessing data quality set forth by Klimisch et al. (1997).

The vapour pressure was determined using a vapour pressure balance with temperature and pressure readings were taken between 75 and 85 °C with a one hour dwell at 75 °C between runs. The sequence of runs was started after a sample of test material had been under vacuum for approximately 142 hours. Linear regression analysis was used to calculate the vapour pressure at 25 °C. Under the conditions of the test, the vapour pressure of the test material has been determined to be <6.7 x 10^-4 Pa at 25 °C.