Registration Dossier

Administrative data

Endpoint:
phototransformation in air
Type of information:
calculation (if not (Q)SAR)
Adequacy of study:
supporting study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Scientifically acceptable method

Data source

Referenceopen allclose all

Reference Type:
other: EPIWIN calculation
Title:
Unnamed
Year:
2018
Reference Type:
other: Estimation Software
Title:
Estimation Programs Interface Suite for Microsoft Windows v4.11 (AOP v1.92)
Author:
US EPA
Year:
2012
Bibliographic source:
Unites States Environmental Protection Agency, Washington DC, USA

Materials and methods

Principles of method if other than guideline:
Calculation using SRC AOP v1.92
GLP compliance:
no

Test material

Constituent 1
Chemical structure
Reference substance name:
2-(methoxymethyl)-3-methyl-aniline
EC Number:
821-826-5
Cas Number:
1472650-01-3
Molecular formula:
C9 H13 N O
IUPAC Name:
2-(methoxymethyl)-3-methyl-aniline
Test material form:
liquid

Study design

Estimation method (if used):
PHOTOCHEMICAL REACTION WITH OH RADICALS
- Concentration of OH radicals: 1500000 molecules/cm3
- Degradation rate constant: 2.70 E-10 cm3/molecules*s
- Computer programme: SRC AOP v1.92
- Other: assuming a 12-hour day

Results and discussion

Dissipation half-life of parent compound
DT50:
1.863 h
Test condition:
The substance is within the applicability domain of the models.
Degradation rate constant
Reaction with:
OH radicals
Rate constant:
0 cm³ molecule-1 s-1

Any other information on results incl. tables

AOP Program (v1.92) Results:

===========================

SMILES : COCc1c(C)cccc1N

CHEM :

MOL FOR: C9 H13 N1 O1

MOL WT : 151.21

------------------- SUMMARY (AOP v1.92): HYDROXYL RADICALS (25 deg C) --------

Hydrogen Abstraction = 6.6630 E-12 cm3/molecule-sec

Reaction with N, S and -OH = 0.0000 E-12 cm3/molecule-sec

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

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

**Addition to Aromatic Rings = 200.0000 E-12 cm3/molecule-sec

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

OVERALL OH Rate Constant = 206.6630 E-12 cm3/molecule-sec

HALF-LIFE = 0.078 Days (24-hr day; 0.5E6 OH/cm3)

HALF-LIFE = 1.863 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

 

Model 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 (model 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 probablywithinthe 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 isnotwithinthe applicability domain of the model if it is a perhalogenated alkanes.

Not Fulfilled

Substance is a secondary, tertiary and heterocyclic amine. Estimated valueshighly uncertain.

Not Fulfilled

3.4

The uncertainty of the prediction
(OECD principle 4)

- n = 667

- correlation coefficient r2= 0.963

- standard deviation = 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 to olefinic bonds

(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

- R Posthumus and W 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.