Ethane- 1,2-diol, propoxylated

Hydrolysis

Link to relevant study record(s)

Reference

Endpoint:

hydrolysis

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2009-05-05 till 2009-09-23

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP guideline study

Reason / purpose for cross-reference:

reference to same study

Qualifier:

according to guideline

Guideline:

OECD Guideline 111 (Hydrolysis as a Function of pH)

Version / remarks:

Council Regulations EC No 440/2008, Guideline Part C – Methods for the Determination of Ecotoxicity, C.7. “Abiotic Degradation: Hydrolysis as a Function of pH” (adopted, May 2008)

Deviations:

no

Principles of method if other than guideline:

In case compounds react chemically with water a hydrolysis reaction takes place. It’s the target of a hydrolysis study to determine whether or not and how fast a compound reacts with water. The reaction kinetics and the influence of temperature and pH value will be determined.

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

Immediately after preparation of the test solutions and after defined time intervals, samples were taken and analyzed by HPLC.

Buffers:

Buffer pH 4: C6H8O7 / NaOH / NaCl, Riedel de Haen, Art.-No.: 33643
Buffer pH 7: KH2PO4 / Na2HPO4, Fluka, Art.-No.: 33646
Buffer pH 9: Na2B4O7 · 10 H2O / hydrochloric acid, Fluka, Art.-No.: 33648

Details on test conditions:

Approx. 22 mg of the test item were weighed into a 250 mL volumetric flask and dissolved and diluted to volume with buffer pH 4. Nitrogen was passed through the solution for 5 min to remove the oxygen. The solution was stirred for 1 h at room temperature, filtered and 10 mL each were pipetted into 20 mL chromatographic vials. The vials were closed and stored at 50°C in a closed dark shaking heat regulator to avoid any photolytic effect. Forevery test point a new vial was used.

Duration:

5 d

pH:

4

Initial conc. measured:

88 mg/L

Duration:

5 d

pH:

7

Initial conc. measured:

92 mg/L

Duration:

5 d

pH:

9

Initial conc. measured:

92 mg/L

Number of replicates:

each time point 2 replicates

Positive controls:

no

Negative controls:

no

Preliminary study:

The test item was found to be soluble in water. Therefore, no further solubility test with organic solvent additives were performed.

Transformation products:

not measured

% Recovery:

> 90

pH:

4

Temp.:

50 °C

Duration:

5 d

% Recovery:

> 90

pH:

7

Temp.:

50 °C

Duration:

5 d

% Recovery:

> 90

pH:

9

Temp.:

50 °C

Duration:

5 d

Remarks on result:

other: Ethane-1,2 -diol, propoxylated, is found to be stable at 50°C at all three pH values (4, 7 and 9). Therefore, it can be assumed that the test item is also stable at 25°C and no half-life times and hydrolysis rates were calculated.

Remarks:

Ethane-1,2 -diol, propoxylated, is found to be stable at 50°C at all three pH values (4, 7 and 9). Therefore, it can be assumed that the test item is also stable at 25°C and no half-life times and hydrolysis rates were calculated.

Because the test item is an NLP and no standard compounds were available for the different fractions the test item was used as standard compound calculated with a stipulated overall content of 100 %. The calibration was only used to check the system suitability and to evaluate the total water solubility. The hydrolysis tests themselves were analyzed using the peak area and the total peak area of main NLP-fractions.

Validity criteria fulfilled:

yes

Remarks:

The recovery is between 90 % und 110 % and meet the requirements of OECD 111.

Executive summary:

Ethane-1,2 -diol, propoxylated, is found to be stable at 50°C at all three pH values (4, 7 and 9). Therefore, it can be assumed that the test item is also stable at 25°C and no half-life times and hydrolysis rates were calculated. Ethane-1,2 -diol, propoxylated as a NLP contains different molecular weight fractions (= NLP-fraction) which behave similar in hydrolysis reaction (Currenta, 2009).

Description of key information

Ethane-1,2 -diol, propoxylated, is found to be stable at 50°C at all three pH values (4, 7 and 9). Therefore, it can be assumed that the test item is also stable at 25°C and no half-life times and hydrolysis rates were calculated. Ethane-1,2 -diol, propoxylated as a NLP contains different molecular weight fractions (= NLP-fraction) which behave similar in hydrolysis reaction (Currenta, 2009).

Additional information

Ethane-1,2 -diol, propoxylated, is found to be stable at 50°C at all three pH values (4, 7 and 9). Therefore, it can be assumed that the test item is also stable at 25°C and no half-life times and hydrolysis rates were calculated. Ethane-1,2 -diol, propoxylated as a NLP contains different molecular weight fractions (= NLP-fraction) which behave similar in hydrolysis reaction (Currenta, 2009).