N1,N3-diallylpropane-1,3-diamine dihydrochloride

Hydrolysis

Link to relevant study record(s)

Reference

Endpoint:

hydrolysis

Type of information:

experimental study

Adequacy of study:

key study

Study period:

02 July 2020 - 18 December 2020

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)

Version / remarks:

13 April 2004

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Radiolabelling:

no

Analytical monitoring:

yes

Details on sampling:

- Sampling intervals for the parent/transformation products: 0h, 2h, 6h, 24h, 48h, 120h and 144h
- Sampling intervals/times for pH measurements: same as above
- Sampling intervals/times for sterility check: not required for preliminary test
- Sample storage conditions before analysis: -20°C in the dark (freezer)

Buffers:

- pH: 4, 7, 9
- Type and final molarity of buffer: pH 4 - acetic acid/acetate buffer, pH 7 - phosphate buffer, Sörensen, pH 9 - borate buffer, Sörensen and Cark
- Composition of buffer:
pH 4:
Stock solution A:
6.005 g of acetic acid were made up to 1000 mL with distilled water.
Stock solution B:
27.216 g of sodium acetate trihydrate (CH3COONa * 3 H2O) were made up to 1000 mL with distilled water.
Buffer solution pH 4.0:
410 mL of stock solution A and 90 mL of stock solution B were made up to 1000 mL with distilled water.

pH 7:
Stock solution A:
9.078 g of potassium dihydrogen phosphate (KH2PO4) were made up to 1000 mL with distilled water.
Stock solution B:
11.876 g of disodium hydrogen phosphate - dihydrate (Na2HPO4 * 2 H2O) were made up to 1000 mL with distilled water.
Buffer solution pH 7.0:
306 mL of stock solution B were made up to 500 mL with stock solution A

pH 9:
Stock solution A:
19.07 g of Borax (Na2B4O7 * 10 H2O) were made up to 1000 mL with distilled water.
Stock solution B:
0.1 M hydrochloric acid
Buffer solution pH 9.0:
150 mL of stock solution B were made up to 1000 mL with stock solution A

Details on test conditions:

TEST SYSTEM
- Type, material and volume of test flasks, other equipment used: a stock solution was prepared in glass-stoppered 50 ml volumetric flasks and used for preparation of test solutions for pH 4, 7 and 9 in 500 mL volumetric flasks (glass). The buffered test solution was then transferred into GC vials (glass) for incubation.
- Sterilisation method: drying oven at 180°C for 4 hours, thermally sensitive caps for GC vials were sterilized in pure ethanol for 2h and then dried. Buffer solutions were sterilised by filtering through a PES 0.22µm filter.
- Lighting: Protected from light
- Measures to exclude oxygen: sealed GC vials
- Is there any indication of the test material adsorbing to the walls of the test apparatus? No
TEST MEDIUM
- Kind and purity of water: double distilled
- Preparation of test medium: For preparation of the stock solution 2501.96 mg (for pH 4 and pH 9), resp. 2494.83 mg (for pH 7) of the test item were weighed into glass-stoppered 50 mL volumetric flasks. Then the substance was dissolved in double distilled water and made up to the mark with the same solvent (resulting concentration 50.04 g/L, resp. 49.90 g/L). The test item was dissolved completely at this concentration. For each pH value a test solution was prepared. For this purpose 10 mL of the stock solution was pipetted into a 500 mL volumetric flask and made up to the mark with the corresponding buffer solution.

Duration:

144 h

pH:

4

Temp.:

50 °C

Initial conc. measured:

1 000.8 mg/L

Duration:

144 h

pH:

7

Temp.:

50 °C

Initial conc. measured:

997.9 mg/L

Duration:

144 h

pH:

9

Temp.:

50 °C

Initial conc. measured:

1 000.8 mg/L

Number of replicates:

2

Positive controls:

no

Negative controls:

no

Preliminary study:

The calculated degradation of below 10 % after 144 h, at pH 4, pH 7 and pH 9 at a testing temperature of 50°C corresponds to a half-life time of more than one year under normal outdoor conditions. Therefore no further testing had to be performed at pH 4, pH 7 and pH 9, according to the mentioned guidelines.

Transformation products:

not measured

% Recovery:

> 90

pH:

4

Temp.:

50 °C

Duration:

144 h

% Recovery:

> 90

pH:

7

Temp.:

50 °C

Duration:

144 h

% Recovery:

> 90

pH:

9

Temp.:

50 °C

Duration:

144 h

Key result

pH:

4

Temp.:

50 °C

DT50:

> 1 yr

Type:

other: estimate

Remarks on result:

hydrolytically stable based on preliminary test

Key result

pH:

7

Temp.:

50 °C

DT50:

> 1 yr

Type:

other: estimate

Remarks on result:

hydrolytically stable based on preliminary test

Key result

pH:

9

Temp.:

50 °C

DT50:

> 1 yr

Type:

other: estimate

Remarks on result:

hydrolytically stable based on preliminary test

Details on results:

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

Table 1: Results of the preliminary test at pH 4.

Sample name	Time of incubation at 50°C [h]	Concentration   [mg/L]	Hydrolysed portion   [%]	pH-value at RT (25±2°C)	Result
Sample 0 h – pH 4	0	1111.1	0.0	4.12	No hydrolysis, no further testing necessary
Sample 2 h – pH 4	2	848.4	23.6	4.12
Sample 6 h – pH 4	6	1209.5	- 8.9	4.11
Sample 24 h – pH 4	24	932.8	16.0	4.10
Sample 48 h – pH 4	72	1158.6	- 4.3	4.10
Sample 120 h – pH 4	120	1138.2	- 2.4	4.10
Sample 144 h – pH 4	144	1129.6	- 1.7	4.10

Table 2: Results of the preliminary test at pH 7.

Sample name	Time of incubation at 50°C [h]	Concentration   [mg/L]	Hydrolysed portion   [%]	pH-value at RT (25±2°C)	Result
Sample 0 h – pH 7	0	1004.4	0.0	7.06	No hydrolysis, no further testing necessary
Sample 2 h – pH 7	2	1001.2	0.4	7.06
Sample 6 h – pH 7	6	1001.1	0.3	7.06
Sample 24 h – pH 7	24	988.4	1.6	7.05
Sample 48 h – pH 7	72	984.2	2.0	7.05
Sample 120 h – pH 7	120	991.2	1.3	7.04
Sample 144 h – pH 7	144	968.0	3.6	7.04

Table 3: Results of the preliminary test at pH 9.

Sample name	Time of incubation at 50°C [h]	Concentration   [mg/L]	Hydrolysed portion   [%]	pH-value at RT (25±2°C)	Result
Sample 0 h – pH 9	0	1049.7	0.0	8.99	No hydrolysis, no further testing necessary
Sample 2 h – pH 9	2	1054.0	- 0.4	9.02
Sample 6 h – pH 9	6	1036.5	1.3	9.02
Sample 24 h – pH 9	24	1040.9	0.8	9.02
Sample 48 h – pH 9	72	1058.0	- 0.8	9.02
Sample 120 h – pH 9	120	1068.8	- 1.8	9.03
Sample 144 h – pH 9	144	1068.3	- 1.8	9.02

Validity criteria fulfilled:

yes

Conclusions:

The calculated degradation of below 10 % after 144 h, at pH 4, pH 7 and pH 9 at a testing temperature of 50°C corresponds to a half-life time of more than one year under normal outdoor conditions. The test substance is hydrolytically stable.

Executive summary:

Hydrolysis of N1,N3-diallylpropane-1,3-diamine dihydrochloride at 1000 mg/L was studied in the dark at 50ºC in sterile aqueous buffered solutions at pH 4 (acetate buffer), pH 7 (phosphate buffer) and pH 9 (borate buffer) for 144 hours. The experiment was conducted in accordance with the OECD 111 guideline and in compliance with the GLP standards. Samples were analysed at 0, 2, 6, 24, 48, 120 and 144 hours by extracting with n-hexane, and the N1,N3-diallylpropane-1,3-diamine dihydrochloride residues were analysed by GC (Agilent 7890b/6890 with CTC Combipal). 

In the preliminary test (Tier 1) at 50°C the test item was stable at pH 4, pH 7 and pH 9 due to the fact that the observed hydrolysis was less than 10% after six days (144 h) at the test temperature of 50°C ± 0.5°C.

According to the test guideline, the half-life (50% decline times) of N1,N3-diallylpropane-1,3-diamine dihydrochloride can be estimated to be more than a year at pH 4, 7 and 9 and at 25°C.

This study is classified acceptable and satisfies the guideline requirement for hydrolysis study.

 

Description of key information

The purpose of this study was to determine the abiotic degradation by hydrolysis as a function of pH of the test item N1,N3-diallylpropane-1,3-diamine dihydrochloride. The test item was incubated at 50 °C and pH 4, 7 and 9 for 144 hours in a preliminary test according to the test guideline OECD 111. Hydrolysis of the test substance was assessed at test start, after 2, 6, 24, 48, 120 and 144 hours by a GC method.

This study was designed to comply with the following methods:

-       Commission Regulation 440/2008/EC, Part C, method C.7.

-       OECD Guideline for Testing of Chemicals No. 111: "Hydrolysis as Function of pH", adopted 13 April 2004

- US EPA Product Properties Test Guideline OCSPP 835.2120

All validity criteria were fulfilled, there were no deviations from the guidelines. N1,N3-diallylpropane-1,3-diamine dihydrochloride was stable at pH 4, pH 7 and pH 9 during the preliminary test (for 144 hours), less than 10% degradation were observed. According to the test guideline a half life of more than one year at 25 °C may therefore be estimated for the test substance at pH 4, pH 7 and pH 9.