2,2'-[oxybis(methylene)]bis[2-ethylpropane-1,3-diol]

Hydrolysis

Link to relevant study record(s)

Reference

Endpoint:

hydrolysis

Type of information:

experimental study

Adequacy of study:

key study

Study period:

6 Jan 2016 - 8 Nov 2016

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:

yes

Remarks:

Limited solubility in solvents meant solutions were prepared on the start day of each timepoint. Stock solutions were prepared accurately at the same nominal concentrations, thus this has no impact on the validity of the test.

GLP compliance:

yes (incl. QA statement)

Radiolabelling:

no

Analytical monitoring:

yes

Details on sampling:

Sampling intervals: Triplicate samples were taken 0, 0.1, 1, and 5 days after treatment.
Sampling procedures: Complete treated samples were removed at each sampling time.
Collection of CO2 and volatile organics: No
Sample storage before analysis: Aliquots of each sample were processed and then test solutions and processed samples were stored frozen (ca -20°C) until analysis.
Verification of pH: The pH was measured at all sampling points from the remaining frozen test solutions. The pH values for the pH 4, 7 and 9 Solutions ranged from pH 3.92 to 3.97; pH 7.91 to 8.16; and pH 8.81 to 8.97, respectively.
Sample Analysis: Dilution factor of samples = 3333.3

Buffers:

pH 4: Ammonium Acetate prepared in Milli-Q Water and buffered with Formic Acid (concentration: 0.05 M)
pH 7: Ammonium Hydrogen Carbonate prepared in Milli-Q Water and buffered with Formic Acid (concentration: 0.05 M)
pH 9: Ammonium Hydrogen Carbonate prepared in Milli-Q Water and buffered with Ammonia (ca 28%) (concentration: 0.05 M)

Details on test conditions:

Temperature: 50 ± 0.5°C (samples placed in water baths monitored and maintained at 50°C)
Lighting: Dark
pH: The pH of each test sample was recorded prior analysis.

Duration:

5 d

pH:

4

Temp.:

50 °C

Initial conc. measured:

2.35 g/L

Duration:

5 d

pH:

7

Temp.:

50 °C

Initial conc. measured:

1.95 g/L

Duration:

5 d

pH:

9

Temp.:

50 °C

Initial conc. measured:

2.56 g/L

Number of replicates:

Three replicates

Positive controls:

not specified

Negative controls:

not specified

Statistical methods:

N/A

Preliminary study:

Results from the preliminary study conducted at 50ºC showed less than 10% degradation after 5 days at pH 4, 7 and 9. No further testing was therefore conducted.

Transformation products:

no

pH:

4

Remarks on result:

hydrolytically stable based on preliminary test

Remarks:

Less than 10% degradation observed in preliminary study

pH:

7

Remarks on result:

hydrolytically stable based on preliminary test

Remarks:

Less than 10% degradation observed in preliminary study

pH:

9

Remarks on result:

hydrolytically stable based on preliminary test

Remarks:

Less than 10% degradation observed in preliminary study

pH:

4

Remarks on result:

hydrolytically stable based on preliminary test

Remarks:

Less than 10% degradation observed in preliminary study

pH:

7

Remarks on result:

hydrolytically stable based on preliminary test

Remarks:

Less than 10% degradation observed in preliminary study

pH:

9

Remarks on result:

hydrolytically stable based on preliminary test

Remarks:

Less than 10% degradation observed in preliminary study

Details on results:

At the termination of the test at 50°C and after 5 days, the concentration of parent compound at pH 4 and 7 had decreased by 8.95 and 6.34%, respectively. No decrease in the concentration of parent compound had occurred at pH 9 after 5 days. The Kobs (hydrolysis rate constant), half life and activation energy values were not calculated due to the low degradation observed.

Validity criteria fulfilled:

yes

Conclusions:

Di(trimethylolpropane) is hydrolytically stable under acidic, neutral or basic conditions.

Executive summary:

A study was conducted according to OECD Guideline 111 (Hydrolysis as a Function of pH) to determine the hydrolytic stability of Di(trimethylolpropane) at pH 4, 7 and 9 in the dark at 50°C.

Di(trimethylolpropane) was applied to sterile aqueous buffers at pH 4, 7 and 9 and the buffers were incubated in the dark at 50 ± 0.5°C for up to 5 days. No degradation was observed in pH 9 buffer and <10% degradation was observed in the pH 4 and 7 buffers, therefore, Di(trimethylolpropane) is considered hydrolytically stable under acidic, neutral and basic conditions.

Description of key information

Less than 10% degradation occurred at pH 4, 7 and 9 at 50°C during the initial investigation of a reliable OECD Guideline 111 ('Hydrolysis as a Function of pH') study. Further testing was therefore not conducted, and Di(trimethylolpropane) was concluded to be hydrolytically stable (Hugill and Markowicz, 2016).