Fatty acids, tall-oil, polymers with glycidyl neodecanoate

Hydrolysis

Link to relevant study record(s)

Reference

Endpoint:

hydrolysis

Type of information:

(Q)SAR

Adequacy of study:

key study

Study period:

2017

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:

The hydrolysis estimations are based on accepted (Q)SAR models. The substance falls within the validity domain of the models.

Principles of method if other than guideline:

Hydrolysis of the test substance was simulated under acidic, basic and neutral conditions using the hydrolysis simulator tool of the (Q)SAR Toolbox v4.0. The predictions were made based on the molecular structure of three main constituents of the UVCB, namely 'glycidyl neodecanoate, ester with stearic acid', 'glycidyl neodecanoate, ester with oleic acid' and 'glycidyl neodecanoate, ester with linoleic acid'.
Half-life of the same three constituents was then estimated using the HydroWin v2 tool of EpiSuite v4.11.

GLP compliance:

no

Transformation products:

not measured

Details on hydrolysis and appearance of transformation product(s):

he results indicate that some breakdown products may be formed under acidic and basic conditions, with a split between the 2,2,3,5 -tetramethylhexanoic acid moiety and the rest of the molecules, then further degradation to fatty acids and glycerol.

Key result

pH:

7

DT50:

> 7 yr

Type:

not specified

Key result

pH:

8

DT50:

> 280 d

Type:

not specified

Details on results:

The results indicate that some breakdown products may be formed under acidic and basic conditions, with a split between the 2,2,3,5 -tetramethylhexanoic acid moiety and the rest of the molecules, then further degradation to fatty acids and glycerol. Under neutral conditions, the tool is inconclusive as it indicates that hydrolysis may or may not occur. HydroWin v2 suggests that, at pH 7 and 8, the hydrolysis half-life will be extremely slow (>7 years and >280 days, respectively).

Validity criteria fulfilled:

yes

Executive summary:

Hydrolysis of the test substance was simulated under acidic, basic and neutral conditions using the hydrolysis simulator tool of the (Q)SAR Toolbox v4.0. The predictions were made based on the molecular structure of three main constituents of the UVCB, namely 'glycidyl neodecanoate, ester with stearic acid', 'glycidyl neodecanoate, ester with oleic acid' and 'glycidyl neodecanoate, ester with linoleic acid'. Half-life of the same three constituents was then estimated at pH 7 and 8 using the HydroWin v2 tool of EpiSuite v4.11. The results indicate that some breakdown products may be formed under acidic and basic conditions, with a split between the 2,2,3,5 -tetramethylhexanoic acid moiety and the rest of the molecules, then further degradation to fatty acids and glycerol. Under neutral conditions, the tool is inconclusive as it indicates that hydrolysis may or may not occur. HydroWin v2 suggests that, at pH 7 and 8, the hydrolysis half-life will be extremely slow (>7 years and >280 days, respectively) (OECD and ECHA, 2017; US EPA, 2012).

Description of key information

Hydrolysis of the test substance was simulated under acidic, basic and neutral conditions using the hydrolysis simulator tool of the (Q)SAR Toolbox v4.0. Overall, the results suggest that hydrolysis under neutral conditions will be extremely slow, with estimated half-lives of >7 years at pH 7 and > 280 days at pH 8.

Key value for chemical safety assessment

Half-life for hydrolysis:

7 yr

Additional information

Hydrolysis of the test substance was simulated under acidic, basic and neutral conditions using the hydrolysis simulator tool of the (Q)SAR Toolbox v4.0. The predictions were made based on the molecular structure of three main constituents of the UVCB, namely 'glycidyl neodecanoate, ester with stearic acid', 'glycidyl neodecanoate, ester with oleic acid' and 'glycidyl neodecanoate, ester with linoleic acid'. Half-life of the same three constituents was then estimated at pH 7 and 8 using the HydroWin v2 tool of EpiSuite v4.11. The results indicate that some breakdown products may be formed under acidic and basic conditions, with a split between the 2,2,3,5 -tetramethylhexanoic acid moiety and the rest of the molecules, then further degradation to fatty acids and glycerol. Under neutral conditions, the tool is inconclusive as it indicates that hydrolysis may or may not occur. HydroWin v2 suggests that, at pH 7 and 8, the hydrolysis half-life will be extremely slow (>7 years and >280 days, respectively) (OECD and ECHA, 2017; US EPA, 2012).