Registration Dossier

Administrative data

Endpoint:
phototransformation in air
Type of information:
(Q)SAR
Adequacy of study:
key study
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Scientifically acceptable calculation method
Justification for type of information:
QSAR prediction: migrated from IUCLID 5.6

Data source

Reference
Reference Type:
other: software application
Title:
US EPA . Estimation Programs Interface Suite™ for Microsoft® Windows, v 4.10 . United States Environmental Protection Agency, Washington, DC, USA ; AOPWIN™ Version 1.92 [2010]
Author:
U.S. Environmental Protection Agency 1200 Pennsylvania Ave., N.W. (Mail Code 7406M) Washington, DC 20460
Year:
2013
Bibliographic source:
http://www.epa.gov/oppt/exposure/pubs/episuite.htm
Report Date:
2013

Materials and methods

Test guideline
Guideline:
other: REACH guidance on QSARs Chapter R.6 , May 2008
Principles of method if other than guideline:
The phototransformation in air of the test substance was determined by calculation with the help of the computer program from US-EPA (EPIWIN software AOPWIN v1.92). This program estimates the gas-phase reaction rate between hydroxyl radicals and the desired chemical. Also the atmospheric half-life is automatically calculated.
GLP compliance:
no
Remarks:
(not applicable)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
not specified
Details on test material:
- Name of test material (as cited in study report) : 2-Pyridineethanol
- SMILES : n(c(ccc1)CCO)c1
Specific details on test material used for the study:
Details on properties of test surrogate or analogue material (migrated information):
Not applicable

Study design

Estimation method (if used):
PHOTOCHEMICAL REACTION WITH OH RADICALS
- Concentration of OH radicals: 1.5 E6 molecules/cm3
- Temperature for which rate constant was calculated: 25°C
- Computer programme: AOPWIN v1.92
- calculated t 1/2 is based on 12 hours
Light source:
not specified
Details on light source:
Not applicable
Details on test conditions:
The computer program estimates the gas-phase reaction rate for the reaction between the most prevalent atmospheric oxidant (hydroxyl radicals) and the desired chemical. For olefins and acetylenes the gas-phase ozone radical reaction rates are estimated as well. Additional information is given by the program if nitrate radical reaction will be important. The assumed average hydroxyl radical and ozone concentration are automatically used to calculate the atmospheric half-live for the chemical of interest.
Reference substance:
no
Remarks:
(not applicable)

Results and discussion

Preliminary study:
Not applicable
Test performance:
No remarks necessary.
Degradation rate constant
Reaction with:
OH radicals
Rate constant:
0 cm³ molecule-1 d-1
Transformation products:
not measured
Results with reference substance:
Not applicable

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Remarks:
(Scientifically accepted calculation method.)
Conclusions:
The study report describes a scientifically accepted calculation method for the phototransformation in air using the US-EPA software AOPWIN v1.92. No GLP criteria are applicable for the usage of this tool and the QSAR estimation is easily repeatable.
Executive summary:

The phototransformation in air of the test substance was determined by the computer program AOPWIN v1.92 (EPIWIN software) by US-EPA . The program estimates the gas-phase reaction rate for the reaction between the most prevalent atmospheric oxidant (hydroxyl radicals) and the desired chemical. For 2-Pyridineethanol an overall gas-phase reaction constant (also called OH rate constant) of 6.2291 E-012 cm³/molecules-sec (= 5.3819 E-007 cm³/molecules-day) and an atmospheric half-life of 1.717 days (20.605 hours) was calculated. Neither an ozone reaction nor any nitrate radical reaction is important for the chemical.