Registration Dossier

Administrative data

Endpoint:
hydrolysis
Type of information:
experimental study
Adequacy of study:
key study
Study period:
13 December 2017 to 06 March 2018
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
guideline study with acceptable restrictions
Remarks:
non GLP

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2018
Report Date:
2018

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 111 (Hydrolysis as a Function of pH)
Principles of method if other than guideline:
a preliminary test was performed
GLP compliance:
no
Remarks:
Quality of the report is similar to that of a report under GLP conditions

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid
Remarks:
soft solid
Specific details on test material used for the study:
The substance was disolved in dichloromethane
Radiolabelling:
no

Study design

Analytical monitoring:
yes
Details on sampling:
Samples were transferred to a measuring cylinder to accurately record the volume of each aliquot and then to a separating funnel.
The sample bottle was rinsed with an aliquot of dicholromethane (DCM) and this rinse added to the separating funnel. 50 ml of DCM was then added to each sample and the funnels transferred to a mechanical shaker for 5 minutes. The sample was allowed to settle and the DCM decanted into conical flasks containing sodium sulphate, then drawn off and transferred to a sodium sulphate drying column. The resulting extract was then concentrated to 1 ml and put into vials ready for analysis and stored in the fridge (3.6ºC).

At pH 9 some undissolved particles were present
Buffers:
- pH: 4
- Composition of buffer: 4ml of 0.1M NaOH + 500ml of 0.1M Potassium phthalate monobasic
- pH: 7
- Composition of buffer: 296.3ml of 0.1M NaOH + 500ml of 0.1M monopotassium phosphate
- pH: 9
Details on test conditions:
TEST SYSTEM
- Type, material and volume of test flasks: amber bottles with 500mL buffer solution
- Sterilisation method: The buffers are sterilised by filtering to 0.2μm, test was not conducted under sterile conditions
- Measures to exclude oxygen: removed from the bottles by passing nitrogen into the head space prior to sealing
TEST MEDIUM
- Volume used/treatment: 500 mL
- Kind and purity of water: deionised water
- Identity and concentration of co-solvent: dichloromethane (<1% v/v)

0.1012g of the substance was weighed directly into a 100ml volumetric flask and made to volume with DCM to give a sample stock concentration of 10.12 mg/l (pH=7.00). 230µl of sample stock was pipetted into amber bottles containing the different buffer solutions (500ml). A spike was also prepared in 500ml of deionised water.
Duration of testopen allclose all
Duration:
5 h
pH:
4
Temp.:
50 °C
Initial conc. measured:
233 mg/L
Remarks:
concentration prepared
Duration:
5 h
pH:
7
Temp.:
50 °C
Initial conc. measured:
233 mg/L
Remarks:
concentration prepared
Duration:
5 h
pH:
9
Temp.:
50 °C
Initial conc. measured:
233 mg/L
Remarks:
concentration prepared
Number of replicates:
not indicated
Negative controls:
yes
Remarks:
deionised water
Statistical methods:
NA

Results and discussion

Preliminary study:
Only a pre-test was performed. The substance is not hydrolitically stable at pH 4, 7 and 9 (see tables)
Transformation products:
not measured
Dissipation DT50 of parent compoundopen allclose all
pH:
4
Temp.:
50 °C
DT50:
< 5 d
Remarks on result:
other: hydrolitically instable based on preliminary test
pH:
7
Temp.:
50 °C
DT50:
< 5 d
Remarks on result:
other: hydrolitically instable based on preliminary test
pH:
9
Temp.:
50 °C
DT50:
< 5 d
Remarks on result:
other: hydrolitically instable based on preliminary test

Any other information on results incl. tables

2.4 Hours

Retention time (mins)

Peak area (%)

Conc (mg/l)

% Recovery

pH4

13

1919

41.239

17.699

pH7

13.00

5110

114.983

49.349

pH9

13.00

1963

42.256

18.136

Spike 13.00

9872

225.033

96.581

 

 

5 Days

Retention time (mins)

Peak area (%)

 Conc (mg/l)

% Recovery

pH4

13

335

4.633

1.988

pH7

13.00

1284

26.564

11.401

pH9

13.00

1251

25.802

11.074

 

Concentration and Hydrolysis

 

Sample Loading mass (g)

 pH

% Recovery after 5 days

Total reaction of substance (%)

A

0.1001

4

1.988

98.012

B

0.1001

7

11.401

88.599

C

0.1001

9

11.074

88.926

 

Applicant's summary and conclusion

Conclusions:
The substance hydrolyses >10% within 5 days at pH, 4, 7 and 9
Executive summary:

In a pre-liminary test performed according OECD 111, recoveries of  the of the substance solution was low for pH 4 (1.988% of initial), pH 7 (11.401% of initial) and pH 9 (11.401%of initial). Due to the low recoveries it  can be asserted that  hydrolysis occurred within all of the pH environments and this was rapid (< 50% recovery at 2.4 hours in all pH environments).

As >10% of the substance has been hydrolysed after 5 days, it is considered hydro-statically unstable under the conditions of this test.