Tris[2-[2-(2-methoxyethoxy)ethoxy]ethyl] orthoborate

Hydrolysis

Link to relevant study record(s)

Reference

Endpoint:

hydrolysis

Type of information:

experimental study

Adequacy of study:

key study

Study period:

April to June 1999

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

The study was conducted according to OECD 111. The following quality criteria of the OECD 111 guideline were not met: 1) No recovery data are available (test was conducted non-radiolabelled) 2) Repeatability and sensitivity of the analytical method are not reported 3) A degradation kinetic was not provided due the analytical method used and the spontaneous hydrolysis of the substance after contact with water Furthermore, decomposition products were not analysed (qualitatively and quantitatively)

Justification for data waiving:

other:

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

OECD Guideline 111 (Hydrolysis as a Function of pH)

Deviations:

yes

Remarks:

Degradation kinetic not provided due to spontaneous hydrolysis, repeatability and sensitivity of the analytical method not provided, decomposition products not analysed

Principles of method if other than guideline:

The IR spectrum of the substance was determined by a NIC magna 500 IR Spectrometer before and after addition of water

GLP compliance:

yes

Radiolabelling:

no

Analytical monitoring:

yes

Details on sampling:

- Sampling intervals for the parent: prior to and after the addition of buffer
- Sampling method: IR measurement of aliquots
- Sampling methods for the volatile compounds, if any:
- Sampling intervals/times for pH measurements: After preparation of buffer, immediately after addition of the test substance
- Sampling intervals/times for sterility check: Not performed
- Sample storage conditions before analysis: information not provided
- Other observation, if any (e.g.: precipitation, color change etc.): no further observations are reported

Buffers:

The test was conducted at 4 pH values (all prepared with deionised water):
1) pH 1.2 (Clark and Lubs - OECD 111, Annex). Effective pH 1.37, definitive pH 1.4 (buffer) and 1.7 (test)
2) pH 4 (Riedel de Haen, citric acid/sodium chloride, sodium hydroxide). Definitive pH 4.0 (buffer) and 4.1 (test)
3) pH 7.0 (Bernd Kraft GmbH, potassium dihydrogen phosphate/disodium hydrogenphosphate), Definitive pH 7.0 (butter), pH 7.1 (test)
4) pH 9.0 (Riedel de Haen, sodium borate/hydrochloric acid); potassium chloride (Merck); hydrochloric acid (2 mol/L, Merck). Definitive pH 9.0 (buffer), pH 8.9 (test)

Estimation method (if used):

NA

Details on test conditions:

TEST SYSTEM
- Type, material and volume of test flasks, other equipment used: not provided
- Sterilisation method: NA
- Lighting: not provided
- Measures taken to avoid photolytic effects: not provided
- Measures to exclude oxygen: NA
- Details on test procedure for unstable compounds: The IR spectrum of the test substance was determined immediately after addition of water.
- Details of traps for volatile, if any: NA
- If no traps were used, is the test system closed/open: Information not provided
- Is there any indication of the test material adsorbing to the walls of the test apparatus? not provided
TEST MEDIUM
- Volume used/treatment: 2 mL buffer (measurement of IR), 1 L buffer (measurement of pH)
- Kind and purity of water: deionized water
- Preparation of test medium: deionized water and four different buffers
- Renewal of test solution: NA
- Identity and concentration of co-solvent: NA
OTHER TEST CONDITIONS
- Adjustment of pH: No
- Dissolved oxygen: no measurements are providedin the report

Duration:

1 h

Initial conc. measured:

other: Qualitative determination of Parent by IR

Number of replicates:

Not provided

Positive controls:

no

Negative controls:

no

Statistical methods:

NA

Test performance:

Nothing is reported (deviations nor amendments)

Transformation products:

not measured

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

Hydrolysis was spontaneously after addition of water

pH:

1.4

DT50:

< 10 min

pH:

4

DT50:

< 10 min

pH:

7

DT50:

< 10 min

pH:

9

DT50:

< 10 min

Other kinetic parameters:

A kinetic was not provided due to spontaneous decomposition of the substance as confirmed by IR spectrum

Details on results:

The substance was spontaneously hydrolysed after addition of water

A representative IR spectrum is provided in the report

Validity criteria fulfilled:

yes

Remarks:

The study was conducted according OECD 111. Quality criteria of the guideline concerning analytical performance are not applicable due to the analytical method used for the analysis of the parent compound (IR)

Conclusions:

The results of the study clearly demonstrate spontaneous hydrolysis of the test substance after contact with water.

Executive summary:

B-TEGME was added to 4 buffer solution, i.e. at pH 1.4, 4, 7 and 9 (2 g substance per 2 mL buffer). The study was conducted under GLP. Measurement of IR spectrum was conducted by a NIC Magna 550 IR spectrometer. Measurement of the solid substance: film between KBr-plates (film thickness 10 micrometers). Measurement after addition of water: Spectra were measured in solution. Approx. 2 g test substance were mixed with 2 mL buffer solution followed by immediate measurement of an IR spectrum in solution. Thereafter the solution was amended by 500 mL buffer and made up to 1 L with deionized water to determine the pH, for further measurements. The IR Spectrum of the solution changed immediately after addition of water, when compared with the IR spectrum of the solid substance. This indicates spontaneous hydrolysis of B-TEGME.

Description of key information

B-TEGME hydrolyses spontaneously after addition of water, at buffers 1.4, 4, 7 and 9.

Key value for chemical safety assessment

Half-life for hydrolysis:

1 d

Additional information

BASF 1999 investigated the hydrolysis of B-TEGME as a function of the pH and confirms the instability of B-TEGME in the environment: B-TEGME was added to 4 buffer solutions of pH 1.4, 4, 7 and 9. The IR spectrum of the solution, taken immediately after addition of water, showed a dramatic change, when compared with the IR spectrum of the original substance. This indicates spontaneous hydrolysis of B-TEGME.

It should be mentioned that in accordance with EC 1907/2006, Annex VIII, point 9.2.2.1, column 2, hydrolysis as a function of the pH is not required since B-TEGME is readily biodegradable, as shown in section 4.1.2.1.2.