(2S)-1-isopropoxy-1-oxopropan-2-yl pivalate

Hydrolysis

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

hydrolysis

Data waiving:

study scientifically not necessary / other information available

Justification for data waiving:

the study does not need to be conducted because the substance is readily biodegradable

Justification for type of information:

JUSTIFICATION FOR DATA WAIVING
In accordance with REACH Annex VIII column 2, hydrolysis study does not need to be conducted because the substance is readily biodegradable.

Reference 2

Endpoint:

hydrolysis

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

No data

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Remarks:

This study was not performed according to international guideline and is not GLP as this is a standard company internal data conducted for global knowledge. This study is well documented and is considered reliable with restrictions.

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 111 (Hydrolysis as a Function of pH)

Version / remarks:

13 April 2004

Deviations:

no

Principles of method if other than guideline:

The aim of the study is to assess the stability of the substance in a series of simple media simulating perfumery applications. The test media are standard aqueous buffers at pH 2, pH 5, pH 7, pH 8.5 and pH 12 containing 1% of non ionic surfactant. The tests are done in accelerated conditions at 40 °C during 3 days

GLP compliance:

no

Specific details on test material used for the study:

No additional information

Radiolabelling:

no

Analytical monitoring:

yes

Details on sampling:

200 – 300 ppm of raw material are dissolved in the pH buffer containing the surfactant (Arkopal N 150) and put into storage in an oven at 40°C. Small aliquots of the test solution are extracted with an organic solvent (typically cyclohexane or ethyl acetate) containing a hydrocarbon standard (typically C12, C17 or C20) on a regular basis throughout the test (typically at time = 0, 0.25, 1, 2, 4, 7, 15, 21 and 28 days). The extracts are analyzed by GC-FID and the results are plotted as (Area/Area Std) expressed in [%]. The measurement at time = 0 is set at 100% and the succeeding measurements are calculated relatively to the time = 0 measurement. Therefore the curves represent the percentage of product remaining in the test solution at the time of analysis.

Buffers:

Buffer solutions:
pH 2 (± 0.1) buffer: Reference Handbook of Chemistry and Physics buffer type A
pH 5 (± 0.1) buffer: Reference Handbook of Chemistry and Physics buffer type C
pH 7 (± 0.1) buffer: Reference Handbook of Chemistry and Physics buffer type D
pH 8.5 (± 0.1) buffer: Reference Handbook of Chemistry and Physics buffer type F
pH 12 (± 0.1) buffer: Reference Handbook of Chemistry and Physics buffer type I

Estimation method (if used):

Not applicable

Details on test conditions:

No data

Duration:

3 d

pH:

2

Temp.:

40 °C

Initial conc. measured:

> 200 - < 300 other: ppm

Duration:

3 d

pH:

5

Temp.:

40 °C

Initial conc. measured:

> 200 - < 300 other: ppm

Duration:

3 d

pH:

7

Temp.:

40 °C

Initial conc. measured:

> 200 - < 300 other: ppm

Duration:

3 d

pH:

8.5

Temp.:

40 °C

Initial conc. measured:

> 200 - < 300 other: ppm

Duration:

3 d

pH:

12

Temp.:

40 °C

Initial conc. measured:

> 200 - < 300 other: ppm

Number of replicates:

1

Positive controls:

no

Negative controls:

no

Statistical methods:

None

Preliminary study:

No data

Test performance:

No data

Transformation products:

no

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

Results showed that the disappearance of the parent compound after 5 and 28 days at 40 °C and at any pH (from 2 to 8.5) is less than 10 %. At higher pH (pH of 12), the parent compound rapidly disappears as of day 1.

% Recovery:

71.32

pH:

2

Temp.:

40 °C

Duration:

48 h

% Recovery:

67.43

pH:

2

Temp.:

40 °C

Duration:

72 h

% Recovery:

86.04

pH:

5

Temp.:

40 °C

Duration:

48 h

% Recovery:

80.76

pH:

5

Temp.:

40 °C

Duration:

72 h

% Recovery:

87.42

pH:

7

Temp.:

40 °C

Duration:

48 h

% Recovery:

85.95

pH:

7

Temp.:

40 °C

Duration:

72 h

% Recovery:

89.88

pH:

8.5

Temp.:

40 °C

Duration:

48 h

% Recovery:

82.56

pH:

8.5

Temp.:

40 °C

Duration:

72 h

% Recovery:

0

pH:

12

Temp.:

40 °C

Duration:

48 h

% Recovery:

0

pH:

12

Temp.:

40 °C

Duration:

72 h

Other kinetic parameters:

None

Details on results:

No additional information

Results with reference substance:

None

Validity criteria fulfilled:

not applicable

Conclusions:

The disappearance of the parent compound after 72 hours (3 days) at 40 °C and at environmentally relevant pH (comprised between 5 and 8.5) is comprised between 14 and 19 %. As the hydrolysis is greater than 10% in the test conditions, the substance is not considered hydrolytically stable at environmentally relevant pH. No half-life values were determined.

Executive summary:

Hydrolysis study was performed similar to OECD Guideline No. 111. The aim of the study is to assess the stability of the substance in a series of simple media simulating perfumery applications. The test media are standard aqueous buffers at pH 2, pH 5, pH 7, pH 8.5 and pH 12 containing 1% of non ionic surfactant (Arkopal N 150). The tests are done in accelerated conditions at 40 °C during 3 days.

200 – 300 ppm of raw material are dissolved in the pH buffer containing the surfactant (Arkopal N 150) and put into storage in an oven at 40°C. Small aliquots of the test solution are extracted with an organic solvent (typically cyclohexane or ethyl acetate) containing a hydrocarbon standard (typically C12, C17 or C20) on a regular basis throughout the test (typically at time = 0, 0.25, 1, 2, 4, 7, 15, 21 and 28 days). The extracts are analyzed by GC-FID and the results are plotted as (Area/Area Std) expressed in [%]. The measurement at time = 0 is set at 100% and the succeeding measurements are calculated relatively to the time = 0 measurement. Therefore the curves represent the percentage of product remaining in the test solution at the time of analysis.

 

The disappearance of the parent compound after 3 days at 40 °C is 32.57% at pH 2, less than 20% (comprised between 14 and 19%) at pH 5, 7 and 8.5, and 100% disappearance at pH 12. It can be concluded that under the conditions of the present test, test substance is not considered hydrolytically stable at environmentally relevant pH.

Description of key information

To assess the hydrolysis potential of the registered substance, a non-GLP stability test was performed on this substance with a method similar to OECD Guideline No. 111. This is a standard company internal data conducted for global knowledge. The test media are standard aqueous buffers at pH 2, pH 5, pH 7, pH 8.5 and pH 12 containing 1% of non ionic surfactant (Arkopal N 150). The test is done in accelerated conditions at 40 °C during 3 days. The disappearance of the parent compound after 3 days at 40°C is 32.57% at pH 2, less than 20% (comprised between 14 and 19%) at pH 5, 7 and 8.5, and 100% disappearance at pH 12. Therefore, it can be concluded that under the conditions of the present test, the registered substance is not considered hydrolytically stable at environmentally relevant pH. However, as the registered substance is readily biodegradable, a GLP hydrolysis study does not need to be conducted, in accordance with REACH Annex VIII column 2. In conclusion, a data waiving is proposed to cover the hydrolysis endpoint of the registered substance and the non-GLP stability test is mentioned in the dossier as a supporting study (this data, performed internally by the lead registrant, cannot be used as a key or weight of evidence study because the test was performed after REACh came into force).