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Link to relevant study record(s)

Reference
Endpoint:
hydrolysis
Type of information:
(Q)SAR
Adequacy of study:
key study
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
Justification for type of information:
1. SOFTWARE
EPI Suite v4.11 Estimation Programs Interface Suite™ for Microsoft® Windows v 4.11. US EPA, United States Environmental Protection Agency, Washington, DC, USA.

2. MODEL (incl. version number)
HYDROWIN v2.00

3. SMILES OR OTHER IDENTIFIERS USED AS INPUT FOR THE MODEL
See “Test material information”

4. SCIENTIFIC VALIDITY OF THE (Q)SAR MODEL
See attached information on the model provided by the developer.

5. APPLICABILITY DOMAIN
See attached information and information as provided in "Any other information on material and methods incl. tables".

6. ADEQUACY OF THE RESULT
See assessment of adequacy as outlined in the "Overall remarks, attachments" section.
Reference:
Composition 0
Qualifier:
according to
Guideline:
other:
Version / remarks:
REACH Guidance on QSARs R.6
Principles of method if other than guideline:
- Software tool(s) used including version: EPI Suite v4.11
- Model(s) used: HYDROWIN v2.00
Full reference and details of the used formulas can be found in:
Mill, T., Haag, W., Penwell, P., Pettit, T. and Johnson, H. "Environmental Fate and Exposure Studies Development of a PC-SAR for Hydrolysis: Esters, Alkyl Halides and Epoxides". EPA Contract No. 68-02-4254: SRI International (1987).
- Model description: see field 'Justification for non-standard information', 'Attached justification' and 'any other information on material and methods'
- Justification of QSAR prediction: see field 'Justification for type of information', 'Attached justification' and/or 'overall remarks'
GLP compliance:
no
Test material information:
Composition 1
Estimation method (if used):
- Total Kb for pH > 8: 1.762E-001 L/mol sec
- Temperature for which rate constant was calculated: 25 °C
- Computer programme: HYDROWIN v2.00
Transformation products:
not specified
pH:
7
Temp.:
25 °C
Half-life:
1.246 yr
pH:
8
Temp.:
25 °C
Half-life:
45.518 d

For detailed information on the results please refer to the attached report. The results refer to the uncharged molecule.

Description of key information

Hydrolysis is not expected (DT50 > 1 yr).

Key value for chemical safety assessment

Additional information

No experimental study is available investigating the hydrolytic degradation of 2-(1,1-dimethylethyl)-6-[[3-(1,1-dimethylethyl)-2-hydroxy-5-methylphenyl]methyl]-4-methylphenyl acrylate (CAS 61167-58-6) in water. First, the substance has an extremely low water solubility of 0.123 μg/L while the limit of quantification is 0.05 μg/L (Smithers Viscient Study No. 13048.7035, 2017). This indicates that it is difficult to determine the hydrolytic half-life experimentally.

Second, the substance has one potential chemicalbondwhich may be subject to hydrolysis (ester bond).Hydrolysis of carboxylic esters is expected to occur under acidic conditions in the presence of strong heator alkaline conditions.However, the substance does not undergo hydrolysis undersuch strong acid conditions in actualenvironment.The half-life is calculated to bea DT50 of > 1 yr at pH7 and 45 d at pH 8 by QSAR calculationsand therefore the calculations suggest that the substance would not be degraded rapidly even under alkaline conditions. Moreover, the ester group is sterically protected by thetert-butyl group as well as the second aromatic ring structure. Thus, fast hydrolysis of the substance is not expected.