3,7-dinitroso-1,3,5,7-tetraazabicyclo[3.3.1]nonane

Biodegradation in water: screening tests

Administrative data

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

22.05.2019 - 06.09.2019

Reliability:

1 (reliable without restriction)

Justification for type of information:

The test was performed under GLP following the standardized test protocol OECD 301B.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2019

Report date:

2019

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test)

Version / remarks:

OECD 301 B / CO2 Evolution Test (adopted July 17, 1992)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

3,7-dinitroso-1,3,5,7-tetraazabicyclo[3.3.1]nonane

EC Number:

202-928-3

EC Name:

3,7-dinitroso-1,3,5,7-tetraazabicyclo[3.3.1]nonane

Cas Number:

101-25-7

Molecular formula:

C5H10N6O2

IUPAC Name:

3,7-dinitroso-1,3,5,7-tetraazabicyclo[3.3.1]nonane

Test material form:

solid

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, non-adapted

Details on inoculum:

Municipal sewage treatment plant, 31137 Hildesheim, Germany
Activated sludge from the sewage plant at Hildesheim is well suited as it receives predominantly municipal sewage and hardly
any industrial chemical waste.
The activated sludge was washed twice with chlorine free tap water. After the second washing the settled sludge was resuspended in mineral salts medium and was maintained in an aerobic condition by aeration with CO2 free air for two days before test start. Further treatment see section ‘preparation of the test vessels’. 4.98 mL/L of this mixture were used to initiate inoculation (25.0 mg/L dw).
Colony forming units: Approx. 10exp7 - 10exp8 CFU/L in the test vessel

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

10.5 mg/L

Based on:

TOC

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

CO2 evolution

Details on study design:

Test Method Duration 28 days
Application Once at test start
Test vessels 5000 mL, brown glass
Volume of the test medium 3000 mL
Test medium Mineral salts medium acc. to OECD 301 B / CO2 Evolution Test
Test temperature Nominal 22 ± 2 °C, actually measured 20.5 – 23.5 °C
Dispersion treatment Continuous stirring
Aeration 30 - 100 mL/min
Photoperiod Low light conditions (brown glass bottles)

Preparation of the test vessels
The concentration of the test item and the theoretical CO2 production (ThCO2) were calculated based on the carbon content.
The necessary amounts of ultrapure water, mineral salts medium and inoculum were placed in each incubation vessel. The vessels were aerated for 24 h with CO2 free air. After 24 h the CO2 adsorption vessels were connected to the air outlets of the incubation vessels via a series of 3 gas wash bottles, each
containing 100 mL of a 0.0125 mol/L Ba(OH)2 solution.
The test item and reference item were weighted out. The test item was weighed out into small beakers. A defined amount of ultrapure water was added to the test item. The test item dispersion and the reference item were transferred to the respective incubation vessel. The vessels were made up to 3 L with ultrapure water and connected to the system for the production of CO2 free air. On day 28, 1 mL 37 % HCl was added to each of the vessels. Aeration was continued for further 24 h and the quantity of CO2 released was determined.

Reference substance

Reference substance:

benzoic acid, sodium salt

Results and discussion

% Degradation

Key result

Parameter:

% degradation (CO2 evolution)

Value:

87

Sampling time:

28 d

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable

Conclusions:

The mean of replicates reached the 10 % level (beginning of biodegradation) within 6 days. Both test item replicates did reach the 60 % pass level within 14 days. The mean biodegradation on day 28 was 87 %. The 10-day window was fulfilled.
The test substance is readily biodegradable

Executive summary:

The mean of replicates reached the 10 % level (beginning of biodegradation) within 6 days. Both test item replicates did reach the 60 % pass level within 14 days. The mean biodegradation on day 28 was 87 %. The 10-day window was fulfilled.

The test substance is readily biodegradable