Registration Dossier

Data platform availability banner - registered substances factsheets

Please be aware that this old REACH registration data factsheet is no longer maintained; it remains frozen as of 19th May 2023.

The new ECHA CHEM database has been released by ECHA, and it now contains all REACH registration data. There are more details on the transition of ECHA's published data to ECHA CHEM here.

Diss Factsheets

Environmental fate & pathways

Hydrolysis

Currently viewing:

Administrative data

Link to relevant study record(s)

Reference
Endpoint:
hydrolysis
Type of information:
experimental study
Adequacy of study:
key study
Study period:
May - Oct 2019
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)
Qualifier:
according to guideline
Guideline:
EU Method C.7 (Degradation: Abiotic Degradation: Hydrolysis as a Function of pH)
Qualifier:
according to guideline
Guideline:
EPA OPPTS 835.2120 (Hydrolysis of Parent and Degradates as a Function of pH at 25°C)
GLP compliance:
yes
Radiolabelling:
no
Analytical monitoring:
yes
Details on sampling:
The concentrations of the test item were determined immediately after preparation (t=0) and at several sampling points after t=0.

Preliminary test
pH4, pH 7, pH 9:
Sampling time 0h, 2.4 hours, 5 days
The concentration of the test item in the test samples was determined immediately after preparation (t=0) and after 2.4 hours and 5 days. The samples taken at t=2.4 hours and t=5 days were cooled to room temperature using running tap water.

Main Test
The concentrations of the test item were determined at:
pH 7, pH 9 and
T20°C, T30°C, T50°C
For example:
pH7, T20°C:
Sampling time [hours]
0.00
140.33
261.93
287.88
330.87
404.18
430.70
475.58
503.65
576.83
675.73
813.80

Main Test pH 9, T20°C:
0.00
1.65
2.53
3.40
4.70
28.93
30.42
30.95
48.05
53.95
72.52
149.53
Buffers:
Acetate buffer pH 4, 0.1 M
Solution of 16.7% 0.1 M sodium acetate in water and 83.3% 0.1 M acetic acid in water. Buffer contained 0.0009% (w/v) sodium azide.
Phosphate buffer pH 7, 0.1 M
Solution of 0.1 M potassium di-hydrogenphosphate in water adjusted to pH 7 using 10N sodium hydroxide. Buffer contained 0.0009% (w/v) sodium azide.
Borate buffer pH 9, 0.1 M
Solution of 0.1 M boric acid in water and 0.1M potassium chloride in water adjusted to pH 9 using 10N sodium hydroxide. Buffer contained 0.0009% (w/v) sodium azide.
Estimation method (if used):
Preliminary Test - Tier 1
The buffer solutions were filter-sterilised through a 0.2 μm FP 30/0.2 CA-S filter
(Whatman, Dassel, Germany) and transferred into a sterile vessel. To exclude oxygen,
nitrogen gas was purged through the solution for 5 minutes. The test item was spiked to the
solutions at a target concentration of 2 mg/L using a spiking solution in methanol. For each
sampling time, duplicate sterile vessels under vacuum were filled with 6 mL test solution and
placed in the dark in a temperature controlled environment at 50.0°C  0.1°C.
The spiking volume was < 1% of the sample volume. Nominal concentrations were not
corrected for the spiking volume.
The concentration of the test item in the test samples was determined immediately after
preparation (t=0) and after 2.4 hours and 5 days. The samples taken at t=2.4 hours and t=5
days were cooled to room temperature using running tap water.
Details on test conditions:
Analysis was performed on subsamples of 750 μL. The samples were diluted in a 3:1 (v:v) ratio with acetonitrile and analyzed.
Blank buffer solutions containing a similar content of blank spiking solution were treated similarly as the test samples and analyzed at t=0.
The pH of each of the test solutions (except for the blanks) was determined at each sampling time.
Duration:
813.8 h
pH:
7
Temp.:
20 °C
Initial conc. measured:
>= 2.1 - <= 2.11 mg/L
Duration:
720.68 h
pH:
7
Temp.:
30 °C
Initial conc. measured:
>= 2.06 - <= 2.07 mg/L
Duration:
173.72 h
pH:
7
Temp.:
50 °C
Initial conc. measured:
>= 2.1 - <= 2.11 mg/L
Duration:
149.53 h
pH:
9
Temp.:
20 °C
Initial conc. measured:
>= 2.07 - <= 2.07 mg/L
Duration:
47.88 h
pH:
9
Temp.:
30 °C
Initial conc. measured:
>= 2.05 - <= 2.06 mg/L
Duration:
23.72 h
pH:
9
Temp.:
50 °C
Initial conc. measured:
>= 2.08 - <= 2.08 mg/L
Number of replicates:
2
Positive controls:
no
Negative controls:
no
Statistical methods:
For testing of pseudo-first order kinetics the mean logarithms of the relative concentrations
between 10% and 90% were plotted against time. At all temperatures linear relationships
were obtained.
The half-life times of the test item were determined according to the model for pseudo-first
order reactions. All logarithms of the relative concentrations were correlated with time using
linear regression analysis.
Preliminary study:
At pH 7 and pH 9, a degree of hydrolysis of ≥ 10% was observed after 5 days. According to
the guideline, the higher Tier test was required to determine the half-life time of the test item.
A degree of hydrolysis of < 10% was observed at pH 4 after 5 days. It demonstrated that the
half-life time of the test item at 25°C is > 1 year. According to the guideline, no further tests
were required.
No test item was detected in the blank buffer solutions.
The mean recoveries of the of the test item containing buffer solutions at t=0 fell within the
criterion range of 90-110%. It demonstrated that the analytical method was adequate to
support the hydrolysis study on the test item.
Transformation products:
not specified
Key result
pH:
4
Temp.:
25 °C
DT50:
> 1 yr
Type:
(pseudo-)first order (= half-life)
Key result
pH:
7
Temp.:
20 °C
Hydrolysis rate constant:
0.001 h-1
DT50:
47 d
Type:
(pseudo-)first order (= half-life)
Key result
pH:
7
Temp.:
30 °C
Hydrolysis rate constant:
0.002 h-1
DT50:
16 d
Type:
(pseudo-)first order (= half-life)
Key result
pH:
7
Temp.:
50 °C
Hydrolysis rate constant:
0.018 h-1
DT50:
38 h
Type:
(pseudo-)first order (= half-life)
Key result
pH:
9
Temp.:
20 °C
Hydrolysis rate constant:
0.02 h-1
DT50:
35 h
Type:
(pseudo-)first order (= half-life)
Key result
pH:
9
Temp.:
30 °C
Hydrolysis rate constant:
0.066 h-1
DT50:
10 h
Type:
(pseudo-)first order (= half-life)
Key result
pH:
9
Temp.:
50 °C
Hydrolysis rate constant:
0.613 h-1
DT50:
1.1 h
Type:
(pseudo-)first order (= half-life)
Validity criteria fulfilled:
yes
Conclusions:
The half-life times of the test item were as follows:
pH 4 pH 7 pH 9
Temperature [°C] t½ Temperature [°C] t½ Temperature[°C] t½
20 47 days 20 35 hours
25 > 1 year 25 27 days 25 19 hours
30 16 days 30 10 hours
50 38 hours 50 1.1 hours

Description of key information

The half-life times of the test item were as follows:

                           pH 4                            pH 7                                                 pH 9

Temperature [°C]       t½              Temperature [°C]       t½       Temperature[°C]              t½

                                                       20                     47 days       20                            35 hours

25                     > 1 year                25                     27 days        25                            19 hours

                                                       30                     16 days        30                            10 hours

                                                       50                     38 hours       50                            1.1 hours

Key value for chemical safety assessment

Half-life for hydrolysis:
27 d
at the temperature of:
25 °C

Additional information