Poly(oxy-1,2-ethanediyl), α-[2-(dide- cylmethylammonio)ethyl]- .omega.- hydroxy-, propanoate (salt) (Bardap 26)

Hydrolysis

Link to relevant study record(s)

Reference

Endpoint:

hydrolysis

Type of information:

experimental study

Adequacy of study:

key study

Study period:

2001-05-02 to 2001-06-15

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method C.7 (Degradation: Abiotic Degradation: Hydrolysis as a Function of pH)

Deviations:

no

Principles of method if other than guideline:

Not relevant.

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
No information provided.

Radiolabelling:

not specified

Analytical monitoring:

yes

Details on sampling:

Sample solutions were prepared in stoppered glass flasks at a nominal concentration of 4 g/L in the three buffer solutions at pH 4, pH 7 and pH 9, using a 1% methanol co-solvent.
The solutions were shielded from light whilst maintained at the test temperature.

Buffers:

pH4, pH7 and pH9
The buffer solutions were filtered through a 0.2 µm membrane filter to ensure they were sterile before commencement of the test. Also these solutions were subjected to ultrasonication and degassing with nitrogen to minimise dissolved oxygen content.

Estimation method (if used):

not applicable.

Details on test conditions:

TEST SYSTEM
- Type, material and volume of test flasks, other equipment used: Stoppered glass flasks.
- Measures taken to avoid photolytic effects: Solutions were shielded from light.

Preliminary test/test 1
The sample solutions at pH 4, 7 and 9 were shielded from light and maintained at 50.0 +/- 0.5°C for a period of 5 days.

Duration:

5 d

pH:

4

Temp.:

50 °C

Initial conc. measured:

2.56 g/L

Duration:

5 d

pH:

7

Temp.:

50 °C

Initial conc. measured:

4.28 g/L

Duration:

5 d

pH:

9

Temp.:

50 °C

Initial conc. measured:

4.18 g/L

Number of replicates:

Duplicate aliquots (A and B).

Positive controls:

no

Negative controls:

no

Statistical methods:

The mean peak area of each standard was corrected to a nominal concentration of 80 mg/L and the mean value taken. The concentration of the sample solutions (g/L) was calculated using Equation 4.1.

Preliminary study:

Preliminary test and test 1 were performed in the same time and buffer conditions.

Test performance:

No degradation occurred during the incubation period.

Transformation products:

not measured

Details on hydrolysis and appearance of transformation product(s):

At all three pH's tested, less than 10% hydrolysis after 5 days at 50degC, equivalent to a half-life greater than 1 year at 25degC.No degradation occurred during the incubation period.

% Recovery:

ca. 100

pH:

4

Temp.:

50 °C

Duration:

120 h

% Recovery:

ca. 100

pH:

7

Temp.:

50 °C

Duration:

120 h

% Recovery:

ca. 100

pH:

9

Temp.:

50 °C

Duration:

120 h

Key result

pH:

4

Temp.:

25 °C

DT50:

> 1 yr

Type:

(pseudo-)first order (= half-life)

Key result

pH:

7

Temp.:

25 °C

DT50:

> 1 yr

Type:

(pseudo-)first order (= half-life)

Key result

pH:

9

Temp.:

25 °C

DT50:

> 1 yr

Type:

(pseudo-)first order (= half-life)

Other kinetic parameters:

No information provided.

Details on results:

N,N-Didecyl-N-methylpoly(oxyethly)ammonium Propionate is hydrolytically stable at 25°C at pH 4, 7 and 9 for over 1 year.
Less than 10% hydrolysis after 5 days at 50°C, equivalent to a half-life greater than 1 year at 25°C.

It was noted that the initial concentration analysed at pH 4 was somewhat lower that the stock fortification concentration. This is possibly due to the solubility of the test material at this pH, as during method development it proved difficult to prepare stock solutions at sufficient concentration for testing at this pH. This was considered not to have affected the result of the test, which was an investigation into rate of hydrolysis, as the test material was seen to be stable at the analysed concentration over the duration of the test.

Validity criteria fulfilled:

yes

Conclusions:

N,N-Didecyl-N-methylpoly(oxyethly)ammonium Propionate is hydrolytically stable at 25°C at pH 4, 7 and 9 for over 1 year, under the conditions of this study.

Executive summary:

In a study conducted in accordance with Directive 92/69/EEC, C.7, the hydrolysis of N,N-Didecyl-N-methylpoly(oxyethly)ammonium Propionate was assessed at a concentration of 4g/L in buffer solutions at pH 4, pH 7 and pH 9. Samples were incubated at 50°C for 5 days and shielded from light. No degradation occurred during the incubation period. N,N-Didecyl-N-methylpoly(oxyethly)ammonium Propionate is hydrolytically stable at 25°C at pH 4, 7 and 9 for over 1 year.

Description of key information

No degradation occurred during the incubation period. N,N-Didecyl-N-methylpoly(oxyethly)ammonium Propionate is hydrolytically stable at 25°C at pH 4, 7 and 9 for over 1 year.

Key value for chemical safety assessment

Half-life for hydrolysis:

1 yr

at the temperature of:

25 °C

Additional information

In a study conducted in accordance with Directive 92/69/EEC, C.7, the hydrolysis of N,N-Didecyl-N-methylpoly(oxyethly)ammonium Propionate was assessed at a concentration of 4g/L in buffer solutions at pH 4, pH 7 and pH 9. Samples were incubated at 50°C for 5 days and shielded from light. No degradation occurred during the incubation period. N,N-Didecyl-N-methylpoly(oxyethly)ammonium Propionate is hydrolytically stable at 25°C at pH 4, 7 and 9 for over 1 year.