Registration Dossier

Administrative data

Endpoint:
vapour pressure
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP- Study performed

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2004
Report date:
2004

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
OECD Guideline 104 (Vapour Pressure Curve)
Deviations:
no
GLP compliance:
yes (incl. QA statement)
Type of method:
gas saturation method

Test material

Constituent 1
Reference substance name:
OS Menthol Ester
IUPAC Name:
OS Menthol Ester
Constituent 2
Chemical structure
Reference substance name:
(1R,2S,5R)-2-isopropyl-5-methylcyclohexyl (2R,5R)-5-hydroxy-1,3-oxathiolane-2-carboxylate
EC Number:
604-569-1
Cas Number:
147126-62-3
Molecular formula:
C14H24O4S
IUPAC Name:
(1R,2S,5R)-2-isopropyl-5-methylcyclohexyl (2R,5R)-5-hydroxy-1,3-oxathiolane-2-carboxylate
Test material form:
solid: compact

Results and discussion

Vapour pressureopen allclose all
Temp.:
30 °C
Vapour pressure:
3.53 Pa
Temp.:
50 °C
Vapour pressure:
4.14 Pa

Any other information on results incl. tables

The results showed that at 30° and 50°C, the test substance degraded into products similar to those observed during exposure to water. None of the starting material, as indicated by a peak at 5.5 minutes in the HPLC chromatogram, was observed.

The crystalline material in the saturation tube was analyzed to determine whether this material had also degraded. The. results showed that it had not, indicating that the degradation occurred while in the vapour state.

An estimate of the amounts of material"present in the vapour was made by calibrating the HPLC using samples of the test substance deliberately degraded in water. These values were used to estimate the vapour pressure. These results are summarized in Table 13. Raw data can be found in Appendix 2.

The measurements show that the test substance displays a vapour pressure of 3.53 Pa at 30°C and 4.14 Pa at 50°C. This result is based on an estimate of the amounts of degradation products present in the imp Inger solutions and assumes that the breakdown products in vapour are the same as occur in water. There was some carryover into the second impinger in each case, but given the nature of the breakdown occurring in the vapour phase, this was not further investigated. Given these analytical uncertainties, the reported vapour pressure must be. considered a crude estimate. Further refinement of the value, would require a significant level of effort beyond the scope of the OECD method.

Applicant's summary and conclusion

Conclusions:
Our measurements show that the vapour pressure of the test substance is 3.53 Pa at 30°C and 4.14 Pa at 50°C. The vapour is composed entirely
of breakdown products which resemble those which occur in water, based on the similarity of the HPLC profiles. The error associated with these
estimates must be considered to be larger than normal because of the unknown structure of the breakdown products and the crude manner in which they were estimated.