2,2',4,4',6,6'-hexanitrostilbene

Biodegradation in water: screening tests

Administrative data

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Report date:

2020

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

EU Method C.4-C (Determination of the "Ready" Biodegradability - Carbon Dioxide Evolution Test)

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

2,2',4,4',6,6'-hexanitrostilbene

EC Number:

243-494-5

EC Name:

2,2',4,4',6,6'-hexanitrostilbene

Cas Number:

20062-22-0

Molecular formula:

C14H6N6O12

IUPAC Name:

1,3,5-trinitro-2-[(E)-2-(2,4,6-trinitrophenyl)ethenyl]benzene

Test material form:

solid: crystalline

Specific details on test material used for the study:

Batch no. 18909-1
Composition 100%
Expiry date 27/2/2028

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic (adaptation not specified)

Details on inoculum:

Source
The sludge was taken from the activation basin of the ESN (Stadtentsorgung Neustadt)
sewage treatment plant, Im Altenschemel, 67435 NW-Lachen-Speyerdorf.
Pre-Treatment
The sludge was filtrated through a cloth, washed with test medium (2x) and re-suspended
in test medium. It was then aerated until use. The dry matter was determined to contain
4.68 g of suspended solids/L.

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

20 mg/L

Based on:

other: organic carbon/Hezanitrostilbene

Results and discussion

% Degradation

Parameter:

% degradation (test mat. analysis)

Value:

2

Sampling time:

28 d

Details on results:

The test item HEXANITROSTILBENE is considered as “not readily biodegradable”.
The degree of biodegradation reached 2 % after 28 days.
The 10-day-window was not detected.
Degradation missed 60 % within 28 days, too. Therefore, the test item is considered as “not ultimately biodegradable within 28 days”, as well.
Abiotic degradation was not observed.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

not readily biodegradable

Conclusions:

When applying the 10-day-window, the test item HEXANITROSTILBENE is not
readily biodegradable following OECD 301B and EU C.4-C respectively. As degradation
missed the pass level of 60% in the course of the test, HEXANITROSTILBENE is considered
as not ultimately biodegradable, within 28 days as well.