Fatty acids, C16-18 (even numbered), reaction products with diethylene triamine, di-Me sulfate quaternized

Hydrolysis

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

hydrolysis

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: see 'Remark'

Remarks:

Guideline study according to EC C.7 (OECD 111) from closely related structural homologue, read-across from supporting substance (structural analogue or surrogate); hypothesis for Read across: oleic acid based IQAC, DMS quaternised is used for read across. The source substance differs only in marginal in the C-length distribution and number and location of double bonds. Hydrolysis is not influenced by that fact.

Qualifier:

according to guideline

Guideline:

OECD Guideline 111 (Hydrolysis as a Function of pH)

Version / remarks:

2004

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Sampling method: 2 ml buffer solution of pH 7 was spiked with the test substance at a target concentration of 0.1 or 1 mg/l. The samples were diluted in a 1:1 (v:v) ratio with acetonitrile containing 0.02% TFA and analyzed. If necessary, the samples were further diluted with 50/50 (v/v) acetonitrile/bufffer solution, of pH 7, containing 0.01% TFA to obtain concentrations within the calibration range.

Buffers:

- pH: Acetate buffer pH = 4, Phosphate buffer pH = 7, Borate buffer pH = 9
- Type and final molarity of buffer: all buffers were 0.01 M
- Composition of buffer: Acetate buffer: solution of 16.6% 0.1 M sodium acetate and 83.4% 0.1 M acetic acid was 10 times diluted with water. Contains 0.00009% (w/v)sodium azide
Phosphate buffer: 0.1 M di-hydrogenphophate adjusted to pH 7 using 10 N sodium hydroxide was 10-times diluted with water and adjusted to pH 7 (if required). The buffers contain 0.00009% (w/v) sodium azide.
Borate buffer: solution of 0.1 M boric acid and 0.1 M potassium chloride adjusted to pH 9 using 10N sodium hydroxide was 10-times diluted with water and adjusted to pH 9 (if required). Contains 0.00009% (w/v)sodium azide.

Details on test conditions:

TEST SYSTEM
- Type, material and volume of test flasks, other equipment used: sterile vessels
- Sterilisation method: filtered through a 0.2 µm FP 30/0.2 CA-S filter (Whatman. Dassel, Germany). The buffer soluitions contained 0-00009% (w/v) sodium azide
- Lighting:
- Measures taken to avoid photolytic effects:
- Measures to exclude oxygen: Nitrogen gas was purged through the system for 5 minutes
- If no traps were used, is the test system closed/open
- Is there any indication of the test material adsorbing to the walls of the test apparatus? not reported
TEST MEDIUM
- Kind and purity of water: Tapwater purified by a Milli-Q water purification system(Millipore. Bedfod, MA. U.S.A.)


OTHER TEST CONDITIONS
- Adjustment of pH: buffer solutions were used

Duration:

408 h

pH:

4

Temp.:

20

Initial conc. measured:

>= 0.99 - <= 1 mg/L

Duration:

410 h

pH:

4

Temp.:

50

Initial conc. measured:

>= 0.838 - <= 0.935 mg/L

Duration:

95 h

pH:

4

Temp.:

60

Initial conc. measured:

>= 0.935 - <= 1.02 mg/L

Duration:

239 h

pH:

7

Temp.:

20

Initial conc. measured:

>= 0.886 - <= 0.904 mg/L

Duration:

78 h

pH:

7

Temp.:

50

Initial conc. measured:

>= 0.84 - <= 0.951 mg/L

Duration:

47 h

pH:

7

Temp.:

60

Initial conc. measured:

>= 0.84 - <= 0.951 mg/L

Duration:

94.5 h

pH:

9

Temp.:

20

Initial conc. measured:

>= 0.736 - <= 0.808 mg/L

Duration:

47.5 h

pH:

9

Temp.:

50

Initial conc. measured:

>= 0.767 - <= 0.857 mg/L

Duration:

78.5 h

pH:

9

Temp.:

60

Initial conc. measured:

>= 0.771 - <= 0.778 mg/L

Number of replicates:

2 for each test condition

Positive controls:

no

Negative controls:

no

Preliminary study:

At all pH values a degree of hydolysis of ≥ 10% after 5 days was observed.

Test performance:

For the test at pH 4, the degree of hydrolysis of < 10% was observed at the data points of 101.5 and 410 hours. Since the test substance was stable at 50 °C for more than 5 days, it was concluded that the half-life of the test substance at 25 °C is > 1 year.
For the test at pH 9, no accurate values for the half-life could be determined at 50 °C or 60 °C. Therefore, the half-life at 25 °C using the Arrhenius equation could not be determined.

Transformation products:

not measured

% Recovery:

100

pH:

4

Temp.:

20 °C

Duration:

408 h

% Recovery:

89

pH:

4

Temp.:

50 °C

Duration:

410 h

% Recovery:

98

pH:

4

Temp.:

60 °C

Duration:

95 h

% Recovery:

90

pH:

7

Temp.:

20 °C

Duration:

239 h

% Recovery:

90

pH:

7

Temp.:

50 °C

Duration:

78 h

% Recovery:

90

pH:

7

Temp.:

60 °C

Duration:

47 h

% Recovery:

77

pH:

9

Temp.:

20 °C

Duration:

94.5 h

% Recovery:

81

pH:

9

Temp.:

50 °C

Duration:

47.5 h

% Recovery:

78

pH:

9

Temp.:

60 °C

Duration:

78.5 h

pH:

4

Temp.:

25 °C

DT50:

> 1 yr

pH:

7

Temp.:

20 °C

Hydrolysis rate constant:

0.01 h-1

DT50:

2.9 d

Type:

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

pH:

7

Temp.:

25 °C

Hydrolysis rate constant:

0.012 h-1

DT50:

2.5 d

Type:

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

pH:

7

Temp.:

50 °C

Hydrolysis rate constant:

0.026 h-1

DT50:

27 h

Type:

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

pH:

7

Temp.:

60 °C

Hydrolysis rate constant:

0.044 h-1

DT50:

16 h

Type:

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

pH:

9

Temp.:

20 °C

Hydrolysis rate constant:

0.024 h-1

DT50:

1.2 d

Type:

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

Details on results:

TEST CONDITIONS
- pH, sterility, temperature, and other experimental conditions maintained throughout the study: Yes

For the hydrolysis at pH 9 at 20°C a linear relationship was obtained. At 50°C and 60°C and pH 9 the test substance decreased rapidly first and then become more stable, but degradation was still observed. A possible reason for the fast degradation at the start of the test was most likely a combination of hydrolysis and interaction with the vessels due to the low water solubility and strong adsorption of the compound at pH 9.

Validity criteria fulfilled:

yes

Conclusions:

Hydrolysis of the test item was studied in the dark at 20ºC, 50 ºC and 60 ºC in sterile aqueous buffered solutions at pH 4 (acetate buffer), pH 7 (phosphate buffer) and pH 9 (borate buffer) for 5 days according to EC C.7 (OECD 111). The half-lives of the test item were at pH 4: > 1 year at 25 °C, at pH7 2.9 days at 20°C, 2.5 days at 25°C, 27 hours at 50 °C and 16 hours at 60 °C, respectively. At pH 9 the half life was 1.2 days at 20 °C.

Executive summary:

Hydrolysis of the test item at 1mg a.i./L was studied in the dark at 20ºC, 50 ºC and 60 ºC in sterile aqueous buffered solutions at pH 4 (acetate buffer), pH 7 (phosphate buffer) and pH 9 (borate buffer) for 5 days.  The experiment was conducted in accordance with the guideline EC C.7 (OECD 111), and in compliance with the OECD-GLP standards.  Samples were analysed by HPLC-Tandem Mass spectrometry. The analytical method was validated in this study.

 

The half-life (lives)/DT50 (50% decline times) of the test item were

 

at pH 4: > 1 year at 25°C

 

at pH7: 2.9 days at 20°C, 2.5 days at 25°C, 27 hours at 50°C and 16 hours at 60°C

 

at pH 9 : 1.2 days at 20°C

 

This study is classified acceptable  and satisfies the guideline requirement for hydrolysis study according to EC C.7 (OECD 111).

 

 

Reference 2

Endpoint:

hydrolysis

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

08.10.2010

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

study well documented, meets generally accepted scientific principles, acceptable for assessment

Principles of method if other than guideline:

Due to experimental difficulties and to the spectral properties of the test substance, the test on hydrolysis was not performed.

GLP compliance:

no

Remarks:

not applicable

Radiolabelling:

no

Validity criteria fulfilled:

not applicable

Conclusions:

Due to experimental difficulties, the spectral properties and low water solubility of the test substance, the test on hydrolysis was not performed.

Executive summary:

The test substance is easily forming emulsions with water. It was not possible to remove the suspension of excess undissolved test substance by either centrifugation or filtration techniques to isolate a suitable aqueous solution for a hydrolysis study. In the guidelines (EC Guideline C.7 and OECD Guideline 111) it is outlined, that the hydrolysis test is only applicable to water soluble substances. In the frame of determing physico-chemical properties, among others the water solubility of the test substance was determined to be 2.6 mg/l using a slow stirring method (see Chapter 4.8). Based on these findings and the requirements of the guidelines, the test on hydrolysis was not performed.

Reference 3

Endpoint:

hydrolysis

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

REPORTING FORMAT FOR THE ANALOGUE APPROACH

1. HYPOTHESIS FOR THE ANALOGUE APPROACH
This read-across is based on the hypothesis that source and target substances have similar physicochemical, ecotoxicological and toxicological properties because
• they are manufactured from similar or identical precursors under similar conditions
• they share structural similarities with common functional groups: quaternary amines, amide bonds, and fatty acid chains with small differences in their chain length distribution and differences in the amount of unsaturated carbon chains
• the metabolism pathway may lead to comparable products: Imidazolium and free fatty acid chains
Therefore, read-across from the existing physicochemical, ecotoxicity and toxicity studies on the source substances is considered as an appropriate adaptation to the standard information requirements of REACH regulation

2. SOURCE AND TARGET CHEMICAL(S) (INCLUDING INFORMATION ON PURITY AND IMPURITIES)
see “Justification for read-across” attached to IUCLID section 13

3. ANALOGUE APPROACH JUSTIFICATION
see “Justification for read-across” attached to IUCLID section 13

4. DATA MATRIX
see “Justification for read-across” attached to IUCLID section 13

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across: supporting information

Transformation products:

not measured

% Recovery:

100

pH:

4

Temp.:

20 °C

Duration:

408 h

Remarks on result:

other: for substance 72749-55-4

% Recovery:

89

pH:

4

Temp.:

50 °C

Duration:

410 h

Remarks on result:

other: for substance 72749-55-4

% Recovery:

98

pH:

4

Temp.:

60 °C

Duration:

95 h

Remarks on result:

other: for substance 72749-55-4

% Recovery:

90

pH:

7

Temp.:

20 °C

Duration:

239 h

Remarks on result:

other: for substance 72749-55-4

% Recovery:

90

pH:

7

Temp.:

50 °C

Duration:

78 h

Remarks on result:

other: for substance 72749-55-4

% Recovery:

90

pH:

7

Temp.:

60 °C

Duration:

47 h

Remarks on result:

other: for substance 72749-55-4

% Recovery:

77

pH:

9

Temp.:

20 °C

Duration:

94.5 h

Remarks on result:

other: for substance 72749-55-4

% Recovery:

81

pH:

9

Temp.:

50 °C

Duration:

47.5 h

Remarks on result:

other: for substance 72749-55-4

% Recovery:

78

pH:

9

Temp.:

60 °C

Duration:

78.5 h

Remarks on result:

other: for substance 72749-55-4

Key result

pH:

4

Temp.:

25 °C

DT50:

> 1 yr

Remarks on result:

other: for substance 72749-55-4

Key result

pH:

7

Temp.:

20 °C

Hydrolysis rate constant:

0.01 h-1

DT50:

2.9 d

Type:

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

Remarks on result:

other: for substance 72749-55-4

Key result

pH:

7

Temp.:

25 °C

Hydrolysis rate constant:

0.012 h-1

DT50:

2.5 d

Type:

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

Remarks on result:

other: for substance 72749-55-4

Key result

pH:

7

Temp.:

50 °C

Hydrolysis rate constant:

0.026 h-1

DT50:

27 h

Type:

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

Remarks on result:

other: for substance 72749-55-4

Key result

pH:

7

Temp.:

60 °C

Hydrolysis rate constant:

0.044 h-1

DT50:

16 h

Type:

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

Remarks on result:

other: for substance 72749-55-4

Key result

pH:

9

Temp.:

20 °C

Hydrolysis rate constant:

0.024 h-1

DT50:

1.2 h

Type:

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

Remarks on result:

other: for substance 72749-55-4

substance (72749 -55 -4):

For the hydrolysis at pH 9 at 20°C a linear relationship was obtained. At 50°C and 60°C and pH 9 the test substance decreased rapidly first and then become more stable, but degradation was still observed. A possible reason for the fast degradation at the start of the test was most likely a combination of hydrolysis and interaction with the vessels due to the low water solubility and strong adsorption of the compound at pH 9.

Validity criteria fulfilled:

yes

Conclusions:

Substance (72749-55-4): Hydrolysis of the test item was studied in the dark at 20ºC, 50 ºC and 60 ºC in sterile aqueous buffered solutions at pH 4 (acetate buffer), pH 7 (phosphate buffer) and pH 9 (borate buffer) for 5 days according to EC C.7 (OECD 111). The half-lives of the test item were at pH 4: > 1 year at 25 °C, at pH7 2.9 days at 20°C, 2.5 days at 25°C, 27 hours at 50 °C and 16 hours at 60 °C, respectively. At pH 9 the half life was 1.2 days at 20 °C.
Substance (98219-51-3): It was not possible to remove the suspension of excess undissolved test substance by either centrifugation or filtration techniques to isolate a suitable aqueous solution for a hydrolysis study.

Executive summary:

Substance (72749 -55 -4): Hydrolysis of the test item at 1mg a.i./L was studied in the dark at 20ºC, 50 ºC and 60 ºC in sterile aqueous buffered solutions at pH 4 (acetate buffer), pH 7 (phosphate buffer) and pH 9 (borate buffer) for 5 days.  The experiment was conducted in accordance with the guideline EC C.7 (OECD 111), and in compliance with the OECD-GLP standards.  Samples were analysed by HPLC-Tandem Mass spectrometry. The analytical method was validated in this study.

 The half-life (lives)/DT50 (50% decline times) of the test item were

 at pH 4: > 1 year at 25°C

 at pH7: 2.9 days at 20°C, 2.5 days at 25°C, 27 hours at 50°C and 16 hours at 60°C

 at pH 9 : 1.2 days at 20°C

 This study is classified acceptable  and satisfies the guideline requirement for hydrolysis study according to EC C.7 (OECD 111).

 

Substance (98219 -51 -3):

The test substance is easily forming emulsions with water. It was not possible to remove the suspension of excess undissolved test substance by either centrifugation or filtration techniques to isolate a suitable aqueous solution for a hydrolysis study. In the guidelines (EC Guideline C.7 and OECD Guideline 111) it is outlined, that the hydrolysis test is only applicable to water soluble substances. In the frame of determing physico-chemical properties, among others the water solubility of the test substance was determined to be 2.6 mg/l using a slow stirring method (see Chapter 4.8). Based on these findings and the requirements of the guidelines, the test on hydrolysis was not performed.

Description of key information

A hydrolysis study for hydrogenated tallow/nortallow based IQAC as well as partially unsaturated IQAC, DMS quaternised are not available. However, there are data for a structurally similar compound, oleic-acid based IQAC, DMS quaternised.

The half-lives of the closely related oleic-acid based IQAC, DMS quaternised were at pH 4: > 1 year at 25 °C, at pH7 2.9 days at 20°C, 2.5 days a t 25°C, 27 hours at 50 °C and 16 hours at 60 °C, respectively. At pH 9 the half life was 1.2 days at 20 °C.

Key value for chemical safety assessment

Half-life for hydrolysis:

2.9 d

at the temperature of:

20 °C

Additional information

Experimental data on hydrolysis of hydrogenated tallow/nortallow based IQAC as well as the structurally similar Partially unsaturated IQAC, DMS quaternised are not available.

Partially unsaturated IQAC, DMS quaternised is easily forming emulsions with water. It was not possible to remove the suspension of excess undissolved test substance by either centrifugation or filtration techniques to isolate a suitable aqueous solution for a hydrolysis study. In the guidelines (EC Guideline C.7 and OECD Guideline 111) it is outlined, that the hydrolysis test is only applicable to water soluble substances. In the frame of determing physico-chemical properties, among others the water solubility of Partially unsaturated IQAC, DMS quaternised was determined to be 2.6 mg/l using a slow stirring method (see Chapter 4.8). Based on these findings and the requirements of the guidelines, the test on hydrolysis is technically not feasible and was therefore not performed. Instead, a read across test from the closely related Oleic-acid based IQAC, DMS quaternised is available. Hydrolysis of the IQAC based on oleic acid was studied in the dark at 20ºC, 50 ºC and 60 ºC in sterile aqueous buffered solutions at pH 4 (acetate buffer), pH 7 (phosphate buffer) and pH 9 (borate buffer) for 5 days according to EC C.7 (OECD 111). The half-lives of the test item were at pH 4: > 1 year at 25 °C, at pH 7 2.9 days at 20°C, 2.5 days at 25°C, 27 hours at 50 °C and 16 hours at 60 °C, respectively. At pH 9 the half life was 1.2 days at 20 °C. The results are deemed to be also reliable for the target substance because the differneces between the substances are limited to alkyl-chain length and unsaturation and these structural properties are not considered to have any influence on hydrolysis.