Dodecanoic acid, 2,2-dimethyl-3-oxopropyl ester

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

Reference 2

Endpoint:

hydrolysis

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

2004-09-27 to 2005-03-21

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: GLP and guideline study, however no hydrolysis guideline was followed

Qualifier:

according to guideline

Guideline:

other: OECD 105 guideline „Water Solubility" , adopted July 27th 1995

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: EU-Guideline A. 6 „Water Solubility" published July 31st 1992

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: OECD: "Partitio n coefficient (n-Octanol/water): slow stirring method"; draft guideline, published Nov. 2003

Deviations:

no

Principles of method if other than guideline:

In the course of the water solubility study, the hydrolysis behaviour of the test substance was recorded.

GLP compliance:

yes (incl. QA statement)

Radiolabelling:

no

Analytical monitoring:

yes

Details on sampling:

After time intervals ranging from 1 hour to 72 hours, samples of the water in the flasks were analysed.
Furthermore, hydrolysis was investigated in a time period from 0 to 24 hours after spiking under oxygen-free conditions.

Buffers:

No buffers were used.

Details on test conditions:

Sample preparation:
Nine round bottom flasks with 250 mL nominal volume were filled with 200 mL water each, degassed with vacuum until boiled for 2 minutes and bubbled with argon. 10 mL water of the first flask were taken and analysed as given above as matrix blank, and to the other eight flasks, 20 µL spiking solution of test item in acetone (concentration 2602 mg/L) were added, giving a nominal concentration of 0.26 mg/L in each flask.

Duration:

72 h

Initial conc. measured:

0.26 mg/L

Positive controls:

no

Negative controls:

yes

Remarks:

blank control

Test performance:

Even after one hour, no aldehyde could be detected and no carbonic acid was produced. Therefore, the experiment was performed a second time, with sampling after 1 minute and after 30 minutes.

Transformation products:

yes

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

Carbon acid was not produced because of the strict absence of oxygen. An explanation for the decrease of test substance concentration is hydrolysis or adsorption, but hydrolysis is more probable because of the increasing background peaks, which implement the formation of decomposition products.

Details on results:

It could be shown that the concentration of the test substance fell below the LOQ within the first hours after spiking. The test item reacts with oxygen-free water in approx. 60 minutes to products other than the carbon acid, the latter being a product of the reaction with oxygen. The appearance of new peaks in the GC-chromotograms indicates the appearance of degradation (hydrolysation) products.

Stability fo the test substance:

- after 1 minutes: peak area (GC) of the test item = 52.9733

- after 30 minutes: peak area (GC) of the test item = 42.8976

Validity criteria fulfilled:

not applicable

Conclusions:

In the course of a study, in which the water solubility of the test substance was determined the hydrolysis of the test substance was clearly observed. The test item reacts with oxygen-free water in approx. 60 minutes to products other than the carbon acid, the latter being a product of the reaction with oxygen.

Executive summary:

In the course of a study, in which the water solubility of the test substance was determined according to OECD guideline no. 105 and EU method A.16 the hydrolysis of the test substance was clearly observed. The test item reacts with oxygen-free water in approx. 60 minutes to products other than the carbon acid, the latter being a product of the reaction with oxygen. The appearance of new peaks in the GC-chromotograms indicates the appearance of degradation products due to hydrolysis.

Description of key information

The performance of hydrolysis as a function of pH is scientifically unjustified.

Regulation (EC) No 1907/2006 (REACH), Annex VIII, Sect. 9.2.2.1, Col. 2, states as follows:

9.2.2.1. The study does not need to be conducted if:

– the substance is readily biodegradable; or

– the substance is highly insoluble in water.

In accordance with column 2 of REACH Annex VIII, hydrolysis as a function of pH was not conducted since the substance  is readily biodegradable and has an estimated low water solubility.

Additional information

Supporting study:

In the course of a study, in which the water solubility of the test substance was determined according to OECD guideline no. 105 and EU method A.16 the hydrolysis of the test substance was clearly observed. The test item reacts with oxygen-free water in approx. 60 minutes to products other than the carbon acid, the latter being a product of the reaction with oxygen. The appearance of new peaks in the GC-chromotograms indicates the appearance of degradation products due to hydrolysis.