3a,4,7,7a-tetrahydro-4,7-methanoindene

Phototransformation in air

Link to relevant study record(s)

Reference

Endpoint:

phototransformation in air

Type of information:

(Q)SAR

Adequacy of study:

key study

Study period:

up to 2010

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: QSAR calculations, acceptable with restrictions

Justification for type of information:

QSAR prediction

Qualifier:

no guideline required

Guideline:

other: QSAR

Principles of method if other than guideline:

The estimation methods used by AOPWIN are based upon the structure-activity relationship (SAR) methods developed by Dr. Roger Atkinson and co-workers. AOPWIN incorporates updated fragment and reaction values as cited in Kwok and Atkinson (1995).
The AOPWIN version used in this study is v.193.

GLP compliance:

no

Remarks:

QSAR

Specific details on test material used for the study:

SMILES: C(C(C=CC12)C1)(C2C=C3)C3
CAS number: 77-73-6

Estimation method (if used):

Measured data from author and other investigators were quality assessed and then used to develop rate constants for different chemicals. The author applied a least squares analysis of degradation rate constants to calculate a preferred value.

Light source:

not specified

Details on light source:

Not reported

Details on test conditions:

Not reported

Reference substance:

no

Remarks:

QSAR

Preliminary study:

Not reported

Test performance:

Not reported

Key result

% Degr.:

50

Sampling time:

1.077 h

Test condition:

OH Rate Constant = 119 E-12 cm^3/molecule-sec. Half-life = 0.090 Days (12 hour day; 1.5E6 OH/cm^3)

Remarks on result:

other: Result from QSAR

Key result

% Degr.:

50

Sampling time:

41.26 min

Test condition:

Ozone Rate Constant = 40.0 E-17 cm^3/molecule-sec. Half-life = 0.029 Days (at 7E11 mol/cm^3)

Remarks on result:

other: Result from QSAR

Transformation products:

not specified

Results with reference substance:

Not reported

Author reports a recommended rate constant of 119 E-12 cm³ molecule^-1sec^-1. Half life is calculated based on this rate constant and a hydroxyl radical concentration of 1.5 E+6 molecule.cm^-3

Overall OH rate constant = 119.1993 E-12 cm³/molecule-sec

Half-life = 0.090 days (12-h day; 1.5E6 OH/cm³)

Half-life = 1.077 h

Overall ozone rate constant = 40.000000 E-17 cm³/molecule-sec

Half-life = 0.029 days (at 7 E+11 mol/cm³)

Half-life = 41.256 min

Validity criteria fulfilled:

not applicable

Remarks:

QSAR

Conclusions:

The overall OH rate constant was calculated to be 119.1993E-12 cm^3 molecule^-1 s^-1

Executive summary:

Measured data from author and other investigators were quality assessed and then used to develop rate constants for different chemicals. Therefore, this value represents a valid rate constant based on all valid studies at the time of publication.

The prediction is considered to fall within the model domain.

Description of key information

Atmospheric photooxidation half-life of 1.077 hours (hydroxyl radicals) has been reported.

Key value for chemical safety assessment

Half-life in air:

1.077 h

Additional information

In Atkinson (1985), measured data from author and other investigators were quality assessed and then used to develop rate constants for different chemicals. Therefore, this value represents a valid rate constant based on all valid studies at the time of publication. The estimated half life is 1.077 hours based on an overall OH rate constant of 119.1993 E-12 cm³ molecule^-1 s^-1.