6,18-dihydrodinaphtho[2,3-i:2',3'-i']benzo[1,2-a:4,5-a']dicarbazole-5,7,12,17,19,24-hexone

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

08 September, 1993 to 14 December, 1993

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 302 C (Inherent Biodegradability: Modified MITI Test (II))

Deviations:

yes

Remarks:

Guideline -Temperature : 20±2°C - Testmedium : Solution A Study Plan Duration : 14 days Instead of 28 days the test has been finished after 14 days since no degradation activity could be observed.

GLP compliance:

yes

Specific details on test material used for the study:

Code number: FAT 46'014/G
EN/Batch: 258645.16
Purity: 99.8 %
Appearance: solid
Solubility: insoluble
Storage: room temperature
Expiration date: 04/98

Oxygen conditions:

aerobic

Inoculum or test system:

other: Mixture of polyvalent bacteria collected 14 September 1993 in the aeration tank of a domestic sewage treatment plant, ARA Basel Communal.

Details on inoculum:

- Concentration of sludge: 30 mg TS/I

Duration of test (contact time):

14 d

Initial conc.:

100 mg/L

Based on:

test mat.

Details on study design:

TEST CONDITIONS
-Water/ Nutrient: According to the specification of the test method
- Temperature: 20 ± 2°C
- Test duration: 14 days
- Lighting: none

Reference substance:

other: Sodium benzoate [Merck Art.Nr. 6290]

Preliminary study:

None

Test performance:

None

Parameter:

% degradation (O2 consumption)

Value:

0

Sampling time:

14 d

Details on results:

None

Results with reference substance:

The biodegradation, (corrected by the inoculum control) expressed as the % of BOD versus ThOD is: 86 % (14 days)

None

Validity criteria fulfilled:

yes

Interpretation of results:

other: not readily biodegradable

Conclusions:

The biodegradation of FAT 46014/G after 14 days was 0 %.

Executive summary:

The ready biodegradability of FAT - 46014/G was determined in a 14 days MITI- Test (I) according to the OECD Guideline for Testing of Chemicals, No. 301C and the EEC-Directive, 79/831, Annex V, C.7. The test was performed in compliance with the Good Laboratory Practice (GLP) Regulations of Switzerland. The test substance was tested in a concentration of 100 mg/l. The reference substance sodium benzoate was also tested in a concentration of 100 mg/l. From the results of the toxicity control, no toxic effect of the biodegradation of the reference substance was observed. The biodegradation of FAT 46014/G after 14 days was 0 %. Hence, it can be concluded that FAT 46014/G is not readily biodegradable.

Description of key information

FAT 46014 is considered to be not biodegradable. 

Key value for chemical safety assessment

Biodegradation in water:

under test conditions no biodegradation observed

Additional information

A study was performed to determine the ready biodegradability of FAT 46014/G in a 14 days MITI Test according to the OECD Guideline for Testing of Chemicals, No. 301C and the EEC-Directive, 79/831, Annex V, C.7., and in compliance with the Good Laboratory Practice (GLP). The test substance was tested at a concentration of 100 mg/l. The reference substance sodium benzoate was also tested at a concentration of 100 mg/l. The percent biodegradation of FAT 46014/G after 14 days was found to be 0 %. Considering the results, FAT 46014/G is considered to be not readily biodegradable. From the results of the toxicity control, no toxic effect of the biodegradation of the reference substance was observed. Several other supporting studies showed the following results:

FAT 46014/A: BOD5 - 56 mg/g O2; COD - 1283.4 mg/g O₂

FAT 46014/B: BOD5 - 190 mg/g O2; COD - 735 mg/g O₂

FAT 46014/C: BOD5 - 220 mg/g O2; COD - 644 mg/g O₂

FAT 46014/E: BOD5 - 38 mg/g O2; COD - 1360 mg/g O₂

FAT 46014/F: BOD5 - 31 mg/g O2; COD - 1385 mg/g O₂

One of the supporting studies which was carried out according to Regulation DEV DIN 38409 - H 41-1 (1980) corresponding to 92/96/EEC C.6 showed a range of COD of 1040-1250 mg O₂/g for FAT 46014/G. 

The BOD5/COD quotient is <0.5 in each case, therefore, the substance is not indicative of rapid degradation. Taking the data from key study and supporting studies into consideration, FAT 46014 is considered to be not biodegradable.