[1,1'-Bianthracene]-9,9',10,10'-tetrone, 4,4'-bis[[4,6-bis[[3-(diethylamino)propyl]amino]-1,3,5-triazin-2-yl]amino]-

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:

2006

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study conducted according to OECD guideline under GLP

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2006

Report date:

2006

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Principles of method if other than guideline:

not relevant

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

308 AQN

IUPAC Name:

308 AQN

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

The activated sludge sample was washed three times by settlement and resuspension in culture medium to remove any excessive amounts of dissolved organic carbon (DOC) that may have been present. The washed sample was then mainteined on continuous aeration in the laboratory at a temperature of approximately 21°C and used on the day of collection. Determination of the suspended solids level of the activated sewage sludge was carried out by filtering a sample (100 ml) of the washed activated sewage sludge by suction through pre-weighted GF/A filter paper using a Buchner funnel. teh filter paper was the dried in an oven at approximately 105°C for at least 1 hour and allowed to cool before weighting. This process was repeated until constant mass was attained. The suspended solids was equal to 2.9 g/l prior to use.

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

7.6 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation 1

Parameter followed for biodegradation estimation:

CO2 evolution

Parameter followed for biodegradation estimation 2

Parameter followed for biodegradation estimation:

DOC removal

Details on study design:

TEST CONDITIONS
- Test temperature: 21℃
- pH: 7.7 tp 7.8
- Suspended solids: 2.9 g/l

TEST SYSTEM
- Culturing apparatus: 300 mL in volume (culture bottle)
- Number of culture flasks/concentration:
> Water degradation test group [water + test substance] (n = 1; Vessel No.1)
> Basic respiration test group [control blank] (n = 1; Vessel No.2)
> Aniline test group [sludge + aniline] (n = 1; Vessel No.3)
> Biodegradation test group [sludge + test substance] (n = 3; Vessel No.4, 5 and 6)
- Method used to create aerobic conditions: stirring
- Measuring equipment: Closed system oxygen consumption measuring apparatus [Coulometer (No. D), Ohkura Electric Co., Ltd.]

SAMPLING
- Sampling frequency: after the termination of the cultivation
- Sampling method: residual amount of the test substance in the test solution (water + test substance), the test solution (control blank) and the test solution (sludge + test substance) were determined
- Sample storage before analysis: no data

CONTROL AND BLANK SYSTEM
- Inoculum blank: yes
- Abiotic sterile control: yes
- Toxicity control: no
- Other: biodegradation control

Reference substance

Reference substance:

benzoic acid, sodium salt

Results and discussion

Preliminary study:

An initial experiment in which the test material was exposed to activated sewage sludge microorganisms at a concentration of 10 mg C/l showed significantly lower inorganic carbon values in the test material vessels than those in the control vessels after 28 days. The toxicity control vessel, containing both the test material and sodium benzoate, also attained lesse than 25% biodegradation after 14 days. This ndicated that, under the strict terms and conditions of the OECD Guidelines, the test material would be classed as exhibiting inhibitory effects.

Test performance:

As the test material would be classed as exhibiting inhibitory effects following the results of the initial test, following the recommendations of the Test Guidelines, in the definitive test, the test materials concentration was reduced to 5 mg C/l to overcome any possible inhibitory effects. It was not possible to distinguish between background CO2 evolution from the inoculum and CO2 evolution due to biodegradation using inorganic carbon analysis.

% Degradation

Parameter:

% degradation (CO2 evolution)

Value:

0

Sampling time:

28 d

Details on results:

Biodegradation toxicity control: 38% after 14 days

BOD5 / COD results

Results with reference substance:

The total CO2 evolution in the control vessels on Day 28 was 22.54 mg/l and therefore satisfied the validation criterion given in the OECD Test Guidelines.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

under test conditions no biodegradation observed

Conclusions:

The test material attained 0% degradation after 28 days and therefore cannot be considered to be readily biodegradable under the strict terms and
conditions of OECD Guideline No 301B.

Executive summary:

The purpose of the study was the ready biodegradability of 308 AQN when exposed to sewage sludge microorganisms under aerobic conditions according to OECD guideline No. 301B (1992).

The test material attained 0% degradation after 28 days and therefore cannot be considered to be readily biodegradable under the strict terms and conditions of OECD Guideline No 301B.

The toxicity control attained 38% degradation after 14 days of the test thereby indicating that the test material was not toxic to the sewage treatment micro-organisms used in the test.

However, the CO2 evolution rates in the test vessels were significantly lower than those in the control vessels after 28 days and were also lower than expected based on that observed in the standard material vessels. It was therefore considered that some inhibition of the activated sewage sludge micro-organisms had occured.

Care should be taken in the interpretation of the results due to the toxic nature of the test material to the activated sewage sludge micro-organisms used in the study.