Registration Dossier

Administrative data

Endpoint:
hydrolysis
Type of information:
experimental study
Adequacy of study:
key study
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: GLP study, EU guideline

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2008
Report Date:
2009

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
EU Method C.7 (Degradation: Abiotic Degradation: Hydrolysis as a Function of pH)
Deviations:
no
GLP compliance:
yes (incl. certificate)
Remarks:
2008-26-05

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
Identification LIPACIDE UG
Identification of the flask LIPACIDE UG; LOT: 0604500008
Batch 0604500008
Supplier SEPPIC
Appearance White/beige powder
Packaging White and opaque plastic flask
Quantity received 1 x 500 g
Date of the reception May 07, 2007
Storage in darkness at room temperature
Identification number for the study 07-050
Radiolabelling:
no

Study design

Analytical monitoring:
yes
Details on sampling:
Preparation of the abiotic degradation solutions
Preparation of the solutions
For the experiment at pH = 5, a quantity of about 35 mg of the test item was weighed (to the nearest 0.1 mg) into a 100-mL Erlenmeyer. A volume of 50 mL of buffer at pH = 5 was added. The LIPACIDE UG concentration was equal to 700 mg/L (about half the saturation concentration).
A second Erlenmeyer flask was prepared at pH = 5.
For the experiment at pH = 7 and pH = 9, a quantity of about 120 mg of the test item was weighed (to the nearest 0.1 mg) into 100-mL Erlenmeyer flasks. A volume of 50 mL of buffer at pH = 7 or pH = 9 was added. The LIPACIDE UG concentration was equal to 2400 mg/L (about 0.01M as the molecular weight of LIPACIDE UG is equal to 241.3 g/mole).
A second Erlenmeyer flask was prepared for pH = 7 and pH = 9.
In order to dissolve the test item in each buffer solution, the Erlenmeyer flasks were treated 5 min. with ultra-sounds and then heated for about 20 min. at a temperature of about 40 °C.
Sampling for analysis
At T = 0 after dissolution of the test item, a volume of 5 mL of the each of the solutions
was transferred into a glass vial.
The Erlenmeyer flasks were then transferred into a water bath at 50 ± 0.5 °C.
At T = 2.4 h and 5 days
The flasks were taken out of the bath and cooled to room temperature for 3 to 5 minutes
before sampling. The sampling was made like at T = 0.
All the collected samplings were frozen at a temperature of minus 15 °C.
Preparation of the test item solutions for the analysis
After defrosting, the samplings were diluted with the mobile phase
- 10 fold for the samplings issued from the experiment at pH = 5,
- 50 fold for the samplings issued from the experiment at pH = 7 and pH = 9
and then analyzed.
Preparation of the analytical instrumental solutions
Preparation of the stock solution
A stock solution of LIPACIDE UG was prepared at a concentration of about 250 mg/L using the mobile phase as solvent.
Preparation of the instrumental solutions
By serial dilutions with the mobile phase, analytical instrumental solutions containing from 200 to 10 mg/L of LIPACIDE UG were prepared.
Buffers:
Preparation of the buffer solutions for the abiotic hydrolysis Buffer at pH 5: For 100 mL of buffer
A quantity of about 1.02 g of potassium hydrogenophtalate was weighed into a 50-mL volumetric flask, the volume was made with water and the solution was treated with ultrasounds.
A volume of about 18 mL of a sodium hydroxide 0.1M* solution and the above solution were transferred into a 100-mL volumetric flask. The flask was made to volume with water and the pH was verified.
Buffer at pH 7: For 100 mL of buffer
A quantity of about 0.68 g of potassium hydrogenophosphate was weighed into a 50-mL volumetric, the volume was made with water and the solution was treated with ultrasounds.
A volume of about 29 mL of sodium hydroxide 0.1M* and the above solution were transferred into a 100-mL volumetric flask. The flask was made to volume with water and the pH was verified.
Buffer at pH 9: For 100 mL of buffer
A quantity of about 0.38 g of potassium chloride and a quantity of about 0.32 g of boric acid were weighed into a 50-mL flask, the volume was made with water and the solution was treated with ultrasounds..
A volume of about 21.3 mL of a sodium hydroxide 0.1M* solution and the above solution were transferred into a 100-mL volumetric flask. The flask was made to volume with water and the pH was verified.
*The sodium hydroxide solution was at 0.097M.
Duration of testopen allclose all
Duration:
5 d
pH:
9
Initial conc. measured:
ca. 2 468 mg/L
Duration:
5 d
pH:
5
Initial conc. measured:
ca. 710 mg/L
Duration:
5 d
pH:
7
Initial conc. measured:
ca. 2 392 mg/L
Number of replicates:
2

Results and discussion

Test performance:
At pH 5, 7 and 9, LIPACIDE UG was practically not hydrolyzed after 5 days.
As in all cases less than 10% hydrolysis of LIPACIDE UG occurs after 5 days, the study was stopped.
Transformation products:
no
Dissipation DT50 of parent compoundopen allclose all
pH:
5
Temp.:
50 °C
Hydrolysis rate constant:
< 10
Remarks on result:
other: <10 % hydrolysis
pH:
7
Temp.:
50 °C
Hydrolysis rate constant:
< 10
Remarks on result:
other: <10 % hydrolysis
pH:
9
Temp.:
50 °C
Hydrolysis rate constant:
< 10
Remarks on result:
other: <10 % hydrolysis

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
At pH 5, 7 and 9, LIPACIDE UG was practically not hydrolyzed after 5 days.
As in all cases less than 10% hydrolysis of LIPACIDE UG occurs after 5 days, the study was stopped.
Executive summary:

Abiotic degradation of LIPACIDE UG pH dependent hydrolysis Preliminary assay

In compliance with EEC Directive 92/69 - Method C7 (1992)

The objective of the study was to define the degradation of the test item during a pH dependent hydrolysis.

The results of the abiotic degradation are summarized as following: At pH 5, 7 and 9, LIPACIDE UG was practically not hydrolyzed after 5 days.

As in all cases less than 10% hydrolysis of LIPACIDE UG occurs after 5 days, the study was stopped.