p-menth-1-en-4-ol

Phototransformation in air

Administrative data

Endpoint:

phototransformation in air

Type of information:

(Q)SAR

Adequacy of study:

other information

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

Data source

Reference

Reference Type:

other: EPISuite calculation

Title:

Unnamed

Year:

2013

Materials and methods

Test guideline

Qualifier:

no guideline followed

Principles of method if other than guideline:

Calculation using AOPWIN v1.92

GLP compliance:

no

Test material

Test material information

Constituent 1

Reference substance name:

p-menth-1-en-4-ol

EC Number:

209-235-5

EC Name:

p-menth-1-en-4-ol

Cas Number:

562-74-3

Molecular formula:

C10H18O

IUPAC Name:

4-methyl-1-(propan-2-yl)cyclohex-3-en-1-ol

Test material form:

liquid

Study design

Estimation method (if used):

PHOTOCHEMICAL REACTION WITH OH RADICALS
- Concentration of OH radicals: 500000/cm³
- Degradation rate constant: 103.95 cm³/molecule-sec
- Temperature for which rate constant was calculated: 25 °C
- Computer programme: SRC AOP v1.92
- Calculated t 1/2 is based on a 24 h day

Results and discussion

Dissipation half-life of parent compound

Key result

DT50:

3.7 h

Test condition:

half-life calculated for the following conditions: sensitizer for indirect photolysis: OH; 0.5 E06 OH/cm³, 24h day;

Remarks on result:

other: substance presumably within applicability domain

Any other information on results incl. tables

Estimate refers to the uncharged molecule.

AOP Program (v1.92) Results:

 

SMILES: OC(CCC(=C1)C)(C1)C(C)C

CHEM: 3-Cyclohexen-1-ol, 4-methyl-1-(1-methylethyl)-

MOL FOR: C10 H18 O1

MOL WT: 154.25

 

Hydrogen Abstraction               = 16.9061 E-12 cm³/molecule-sec

Reaction with N, S and -OH     = 0.1400 E-12 cm³/molecule-sec

Addition to Triple Bonds           = 0.0000 E-12 cm³/molecule-sec

Addition to Olefinic Bonds        = 86.9000 E-12 cm³/molecule-sec

Addition to Aromatic Rings       = 0.0000 E-12 cm³/molecule-sec

Addition to Fused Rings           = 0.0000 E-12 cm³/molecule-sec

 

OVERALL OH Rate Constant    = 103.9461 E-12 cm³/molecule-sec

HALF-LIFE                               = 0.154 Days (24-hr day; 0.5E6 OH/cm³)

HALF-LIFE                               = 3.704 Hrs

Applicant's summary and conclusion

Executive summary:

QPRF: AOPWIN 1. Substance See "Test material identity 2.  General information 2.1 Date of QPRF See “Data Source (Reference)” 2.2 QPRF author and contact details See “Data Source (Reference)” 3. Prediction 3.1 Endpoint (OECD Principle 1) Endpoint Phototransformation in air Dependent variable Hydroxyl reaction rate constant (cm³/molecule*sec) 3.2 Modul or submodel name AOPWIN Model version 1.92 Reference to QMRF QMRF: Estimation of Atmospheric Degradation Using AOPWIN v1.92 (EPI Suite v4.11): Hydroxyl Radical Reaction Predicted value (modul result)  See “Results and discussion” Input for prediction Chemical structure via CAS number or SMILES Descriptor values structure fragments 3.3 Algorithm (OECD Principle 2) Domain (On-Line AOPWIN User’s Guide): As the complete training sets for AOPWIN's estimation methodology are not available, describing a precise estimation domain for this methodology is not possible. There is no information on the number of instances of fragments in the training dataset. If the substance is a member of one of the following chemical classes, the substance is probably within the applicability domain of the model (based on information by other authors, e.g. Posthumus and Slooff, 2001): alkanes, haloalkanes, alkenes, haloalkenes, polyenes, terpenes, alkynes, aldehydes, ketones, alcohols, glycols, ethers, esters, epoxides, thiols, thioethers, aliphatic amines, hydrazines, nitrites, nitrates, nitriles, P-containing organics, aromatic compounds (alkylbenzenes, halobenzenes, phenols, PAHs, styrene, methoxybenzene, aniline, nitrobenzene, biphenyl, dibenzofurans, dibenzodioxins) Fulfilled The substance is not within the applicability domain of the model if it is a perhalogenated alkanes. Not fulfilled Substance is a secondary, tertiary and heterocyclic amine. Estimated values highly uncertain. Fulfilled 3.4 The uncertainty of the prediction (OECD principle 4) - n = 667 -correlationcoefficient r2= 0.963 - standarddeviation = 0.218 - absolute mean error = 0.127 - 90% of the estimated rate constants within a factor of two of the experimental data - 95% of the estimated rate constants within a factor of three of the experimental data 3.5 The chemical mechanisms according to the model underpinning the predicted result (OECD principle 5) Reaction rate constants for hydroxyl radicals are the summation of the following mechanisms: (1) Hydrogen abstraction (2) Reaction with specific nitrogen and sulphur fragments and reaction with hydroxyl (OH) fragments such as alcohols and phenols (3) Addition to triple bonds (4) Addition toolefinicbonds (5) Addition to aromatic rings (6) Addition to fused rings The model works according to the group contribution method which uses fragments and the corresponding reaction values to estimate the reaction rate constant of a given substance.

References - Posthumus and Slooff (2001). Implementation of QSARs in ecotoxicological risk assessments. RIVM report 601516 003. Online: http://rivm.openrepository.com/rivm/bitstream/10029/9559/1/601516003.pdf

- US EPA (2012). On-Line AOPWIN User’s Guide.