2-Propenamide, N-(2-hydroxyethyl)-

Hydrolysis

Link to relevant study record(s)

Reference

Endpoint:

hydrolysis

Type of information:

experimental study

Adequacy of study:

key study

Study period:

23 July 2007 to 6 September 2007

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 111 (Hydrolysis as a Function of pH)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.7 (Degradation: Abiotic Degradation: Hydrolysis as a Function of pH)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Radiolabelling:

no

Analytical monitoring:

yes

Details on sampling:

- Sampling intervals for the parent/transformation products: 5 min, 2.4 hours and 120 hours.
- Sampling method: At each sampling time, duplicate samples were removed from the waterbath and an aliquot (1 ml) was diluted to volume (100 ml) with acetone for analysis by gas chromatography (GC). Additional data were obtained at pH 9 with filtration (0.2 μm, PTFE) prior to analysis, as it was apparent that precipitation of buffer salts from solution at this pH value caused some deterioration in the chromatography.

Buffers:

- pH: 4.0
- Type and final molarity of buffer:
- Composition of buffer:Potassium dihydrogen orthophosphate (3.00 g) and disodium hydrogen orthophosphate dodecahydrate (6.42 g) were dissolved in purified water (950 ml) and the pH was adjusted to 4.0 ± 0.05 with orthophosphoric acid. The volume was
then adjusted to 1000 ml with purified water.

- pH: 7.0
- Type and final molarity of buffer:
- Composition of buffer:Potassium dihydrogen orthophosphate (6.82 g) was dissolved in purified water (950 ml) and 1M sodium hydroxide (30 ml) was added to produce a solution of pH 7.0 ± 0.05. The volume was then adjusted to 1000 ml with purified water.

- pH: 9.0
- Type and final molarity of buffer:
- Composition of buffer:Disodium tetraborate decahydrate (16.6 g) and potassium dihydrogen orthophosphate (1.80 g) were dissolved in purified water (950 ml) to produce a solution of pH 9.0 ± 0.05. The volume was then adjusted to 1000 ml with purified water.

Details on test conditions:

TEST SYSTEM
- Type, material and volume of test flasks, other equipment used: 10 mL Wheaton vials
- Measures taken to avoid photolytic effects: samples were placed in a 50oC water batch in the dark until sampling was required.

Duration:

120 h

pH:

9

Temp.:

50 °C

Initial conc. measured:

0.88 g/L

Duration:

120 h

pH:

7

Temp.:

50 °C

Initial conc. measured:

0.96 g/L

Duration:

120 h

pH:

4

Temp.:

50 °C

Initial conc. measured:

1.03 g/L

Number of replicates:

2 replicates at each pH

Preliminary study:

Results from the preliminary investigation showed that there was no significant change in the concentration of HEAA when incubated in pH 4, 7 and 9 buffer solutions at 50 ± 0.5ºC. Less than 10% hydrolysis had occurred after 120 hours (5 days) under these conditions, equivalent to a half-life of greater than 1 year under environmental conditions (25°C).
Two sets of results are presented for the pH 9 test, from the analyses of both filtered and unfiltered samples. Although there was some variability in the results, it was evident that no significant hydrolysis had occurred when all the data were considered as a single set.

Transformation products:

not measured

% Recovery:

> 90

pH:

4

Temp.:

50

Duration:

120 h

% Recovery:

> 90

pH:

7

Temp.:

50

Duration:

120 h

% Recovery:

> 90

pH:

9

Temp.:

50

Duration:

120 h

pH:

4

Remarks on result:

hydrolytically stable based on preliminary test

pH:

7

Remarks on result:

hydrolytically stable based on preliminary test

pH:

9

Remarks on result:

hydrolytically stable based on preliminary test

Validity criteria fulfilled:

yes

Conclusions:

HEAA was determined to be hydrolytically stable under acidic, neutral and basic conditions.

Executive summary:

The hydrolysis test was performed in accordance with the preliminaty test as described in EU Method C7 and OECD Guideline 111.

Results from the preliminary investigation showed that there was no significant change in the concentration of HEAA when incubated in pH 4, 7 and 9 buffer solutions at 50 ± 0.5ºC. HEAA was determined to be hydrolytically stable under acidic, neutral and basic conditions.

Description of key information

The preliminary study showed that at pH 4, 7 and 9 and 50 ± 0.5ºC, less than 10% hydrolysis had occurred after 120 hours (5 days), equivalent to a half-life of greater than 1 year under environmental conditions (25°C).

HEAA was determined to be hydrolytically stable under acidic, neutral and basic conditions.

Key value for chemical safety assessment

Half-life for hydrolysis:

1 yr

at the temperature of:

25 °C