Fatty acids, C12-16 (even numbered) and C18 unsatd., Me esters

Phototransformation in air

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

phototransformation in air

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Remarks:

Calculation for main component of Fatty acids, C12-16 and C18-unsaturated, methyl esters

Justification for type of information:

see more details on method validity in "Any other information on material and methods".

Principles of method if other than guideline:

Calculation based on AOPWIN v1.92, Estimation Programs Interface Suite™ for Microsoft® Windows v 4.10. US EPA, United States Environmental Protection Agency, Washington, DC, USA.

GLP compliance:

no

Estimation method (if used):

PHOTOCHEMICAL REACTION WITH OH RADICALS
- Concentration of OH radicals: 0.5E+06 radicals/cm3
- Degradation rate constant: 13.1942 E-12 cm3/molecule-sec
- Temperature for which rate constant was calculated: 25 °C
- Computer programme: AOPWIN v1.92

Key result

DT50:

29.2 h

Test condition:

calculation based on 24 h day

For detailed description on the model and its applicability, see "Any other information on materials and methods incl. tables". The estimation is based on a 24 hour day.

Reference 2

Endpoint:

phototransformation in air

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Remarks:

Calculation for main component of Fatty acids, C12-16 and C18-unsaturated, methyl esters

Justification for type of information:

see more details on method validity in "Any other information on material and methods".

Principles of method if other than guideline:

Calculation based on AOPWIN v1.92, Estimation Programs Interface Suite™ for Microsoft® Windows v 4.10. US EPA, United States Environmental Protection Agency, Washington, DC, USA.

GLP compliance:

no

Estimation method (if used):

PHOTOCHEMICAL REACTION WITH OH RADICALS
- Concentration of OH radicals: 0.5E+06 radicals/cm3
- Degradation rate constant: 18.8464 E-12 cm3/molecule-sec
- Temperature for which rate constant was calculated: 25 °C
- Computer programme: AOPWIN v1.92

Key result

DT50:

20.4 h

Test condition:

calculation based on 24 h day

For detailed description on the model and its applicability, see "Any other information on materials and methods incl. tables". The estimation is based on a 24 hour day.

Reference 3

Endpoint:

phototransformation in air

Type of information:

(Q)SAR

Adequacy of study:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

results derived from a valid (Q)SAR model and falling into its applicability domain, with adequate and reliable documentation / justification

Remarks:

Calculation for main component of Fatty acids, C12-16 and C18-unsaturated, methyl esters

Justification for type of information:

see more details on method validity in "Any other information on material and methods".

Principles of method if other than guideline:

Calculation based on AOPWIN v1.92, Estimation Programs Interface Suite™ for Microsoft® Windows v 4.10. US EPA, United States Environmental Protection Agency, Washington, DC, USA.

GLP compliance:

no

Estimation method (if used):

PHOTOCHEMICAL REACTION WITH OH RADICALS
- Concentration of OH radicals: 0.5E+06 radicals/cm3
- Degradation rate constant: 74.7180 E-12 cm3/molecule-sec (cis-isomer)
82.3180 E-12 cm3/molecule-sec (trans-isomer)
- Ozone rate constant: 13.0 E-17 cm3/molecule-sec (cis-isomer)
20.0 E-17 cm3/molecule-sec (trans-isomer)
- Temperature for which rate constant was calculated: 25 °C
- Computer programme: AOPWIN v1.92

DT50:

5.1 h

Test condition:

calculation based on 24 h day (cis-isomer)

DT50:

4.7 h

Test condition:

calculation based on 24 h day (trans-isomer)

For detailed description on the model and its applicability, see "Any other information on materials and methods incl. tables". The estimation is based on a 24 hour day.

Half-life Ozone reaction:

Cis-isomer= 2.11 hours (at 7E11 mol/cm3)

Trans-isomer= 1.375 hours (at 7E11 mol/cm3)

Description of key information

Not relevant due to low vapour pressure

Additional information

No experimental data evaluating the potential for photodegradation of Fatty acids, C12-16 (even numbered) and C18 unstd., methyl esters (CAS No. 1234694-02-0) in air are available. As the substance is a complex UVCB substance, QSAR calculations on representative fatty acid components (C12, C16 and C18 unsaturated) have been performed (AOPWIN v1.92), resulting in estimated half-lives (DT50 values) of 29.2 (C12), 20.4 hours(C16) and 4.7-5.1 hours (C18 unsaturated; by reaction with OH radicals, 24h-day (López Parrón, 2011)).The values obtained for the representative components indicate that Fatty acids, C12-16 and C18 unstd., methyl esters is susceptible to indirect photodegradation in air. Nevertheless, based on its low vapour pressure value (≤ 0.96 Pa) the substance is not expected to be present in the atmosphere in significant amounts. Therefore, photodegradation in air is not a relevant environmental fate process for Fatty acids, C12-16 (even numbered) and C18 unstd., methyl esters. As this study is not a standard information requirement according to Regulation (EC) No. 1907/2006 and there is no indication from the CSA according to Annex I on the need to investigate further the fate and behavior of the substance (Annex X requirement), no testing is considered necessary.