Registration Dossier

Administrative data

Endpoint:
phototransformation in air
Type of information:
(Q)SAR
Adequacy of study:
other information
Study period:
2014
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: QSAR-models with established scientific validity
Justification for type of information:
QSAR prediction: migrated from IUCLID 5.6

Data source

Reference
Reference Type:
other: Helpfiles of the EPI-Suite
Title:
Estimation Programs Interface Suite™ for Microsoft® Windows, v 4.11: AOP Program (v1.92)
Author:
United States Environmental Protection Agency, Washington, DC, USA.
Year:
2012
Bibliographic source:
http://www.epa.gov/oppt/exposure/pubs/episuitedl.htm
Report Date:
2014

Materials and methods

Test guideline
Guideline:
other: Guidance on information requirements and chemical safety assessment Chapter R.6: QSARs and grouping of chemicals (May 2008)
Principles of method if other than guideline:
Estimation Program Interface EPI Suite (TM) v4.11: AOP Program (v1.92) for estimation of Hydroxyl Radical Reaction Half-Life.
GLP compliance:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
pure substance

Study design

Estimation method (if used):
Diethyl hydrogen phosphite does not contain chromophores that absorb at wavelengths >290 nm and therefore is not expected to be susceptible to direct photolysis by sunlight. Lyman WJ et al; Handbook of Chemical Property Estimation Methods. Washington, DC: Amer Chem Soc pp. 8-12 (1990)
Vapor-phase diethyl hydrogen phosphite is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals.
Half life of the substance ubder athmospheric conditions is calculated by Estimation Program Interface EPI Suite (TM) v4.11: AOP Program (v1.92) for estimation of Hydroxyl Radical Reaction Half-Life.
Light source:
other: not applicable
Details on test conditions:
not applicable
Reference substance:
no

Results and discussion

Degradation rate constant
Reaction with:
OH radicals
Rate constant:
38.629 cm³ molecule-1 s-1

Any other information on results incl. tables

AOP Program (v1.92) Results:

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

SMILES : O=P(OCC)OCC

CHEM : Phosphonic acid, diethyl ester

MOL FOR: C4 H11 O3 P1

MOL WT : 138.10

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

Hydrogen Abstraction = 38.6286 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 = 0.0000 E-12 cm3/molecule-sec

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

OVERALL OH Rate Constant = 38.6286 E-12 cm3/molecule-sec

HALF-LIFE = 0.277 Days (12-hr day; 1.5E6 OH/cm3)

HALF-LIFE = 3.323 Hrs

Applicant's summary and conclusion

Validity criteria fulfilled:
not applicable
Remarks:
QSAR
Executive summary:

Vapor-phase diethyl hydrogen phosphite is degraded in the atmosphere by reaction with photochemically-produced hydroxyl radicals; the half-life for this reaction in air is estimated to be 3.323 hours, calculated from its rate constant of 38.6286 E-12 cm3/molecule-sec at 25 deg C