(E)-3-(benzyl(4-((4-nitrophenyl)diazenyl)phenyl)amino)propanenitrile

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:

30 September 1998 to 28 October 1998

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Study conducted to EU test guidance in compliance with GLP.

Qualifier:

according to guideline

Guideline:

EU Method C.4-E (Determination of the "Ready" Biodegradability - Closed Bottle Test)

Deviations:

no

GLP compliance:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic (adaptation not specified)

Details on inoculum:

Type: mixed population of aquatic micro-organisms (activated sludge)
Origin: secondary effluent of a domestic sewage treatment plant (Klaranlage Odenthal)
Date of collection: 25.09.1998
Pre-treatment: none

Duration of test (contact time):

28 d

Initial conc.:

3.3 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

Test substance
Name of test substance: T-9601
Remarks: direct weighing
Initial concentration: 3.3 ± 0.2 mg/l test substance

Reference substance
Name of reference substance: Aniline
Purity: at least 99.5 %
Initial concentration: 2.0 mg/l reference substance

Inoculum
Source of sewage effluent: secondary effluent of a domestic sewage treatment plant (Klaranlage Odenthal)
Treatment given: separation of coarse particles by filtration
Concentration of effluents in reaction mixture: 5ml/I (SOP 2030-6600102-96 D)
Preconditioning: aeration for 5 days

Study conditions
Duration: 28 days
Test temperature: 20 ± 1 °C

Reference substance:

aniline

Preliminary study:

Not conducted.

Test performance:

The test performed in accordance with the specifications detailed within the guideline.

Parameter:

% degradation (O2 consumption)

Value:

1

Sampling time:

28 d

Details on results:

The substance achieved only 1% biodegradation within 28-days, and cannot be considered as readily biodegradable.

Results with reference substance:

In parallel preparations with the reference substance aniline a degradation of 66 % was achieved within 14 days.

Oxygen measurement

Test substance: T-9601

Reference substance: Aniline

 

Dissolved oxygen of blank inoculum: (mg O2 after x days)

Bottle No.	0 days	Bottle No.	7 days	Bottle No.	14 days	Bottle No.	21 days	Bottle No.	28 days
1	9.40	3	8.93	5	8.83	7	8.86	9	8.81
2	9.39	4	9.10	6	9.02	8	9.00	10	8.79
Mean	9.40		9.02		8.93		8.93		8.80

 

Dissolved oxygen of reference substance: (mg O2 after x days)

Bottle No.	0 days	Bottle No.	7 days	Bottle No.	14 days	Bottle No.	21 days	Bottle No.	28 days
11	9.41	13	6.81	15	5.86	17	5.33	19	4.75
12	9.40	14	6.71	16	5.66	18	5.32	20	4.94
Mean	9.41		6.76		5.76		5.33		4.85

 

Dissolved oxygen of test substance: (mg O2/l after x days)

Bottle No.	0 days	Bottle No.	7 days	Bottle No.	14 days	Bottle No.	21 days	Bottle No.	28 days
41	9.36	43	8.94	45	8.90	47	8.86	49	8.79
42	9.34	44	8.99	46	8.97	48	8.84	50	8.68
Mean	9.35		8.97		8.94		8.85		8.72

 

Dissolved oxygen of toxicity control: (mg O2/l after x days)

Bottle No.	0 days	Bottle No.	7 days	Bottle No.	14 days	Bottle No.	21 days	Bottle No.	28 days
51	9.33	53	6.05	55	5.53	57	4.88	59	5.04
52	9.33	54	6.54	56	5.48	58	5.01	60	5.11
Mean	9.33		6.30		5.50		4.95		5.08

 

Results – DO depletion: % Degradation

 

Test substance Test concentration: 3.3 ± 0.2 mg/l ThOD: 1827 mg/g COD: ---mg/g	DO depletion after n days [mg/l]
	7 d	14 d	21 d	28 d
No. 1: (mt0 – mtx) – (mb0 – mbx)	0.04	0.00	0.03	0.00
No. 2: (mt0 – mtx) – (mb0 – mbx)	0.00	0.00	0.03	0.06
D1: % Degradation	1	0	0	0
D2: % Degradation	0	0	0	1
D, Mean	1	0	0	1

 

Reference substance Test concentration: 2.0 mg/l ThOD: 2409 mg/g COD: --- mg/g	DO depletion after n days [mg/l]
	7 d	14 d	21 d	28 d
No 1: (mt0 – mtx) – (mb0 – mbx)	2.22	3.08	3.61	4.06
No. 2: (mt0 – mtx) – (mb0 – mbx)	2.31	3.27	3.61	3.86
D1: % Degradation	46	64	75	84
D2: % Degradation	48	68	75	80
D, Mean	47	66	75	82

 

* Toxicity control	DO depletion after n days [mg/l]
	7 d	14 d	21 d	28 d
No.1: (mt0 – mtx) – (mb0 – mbx)	2.90	3.34	3.98	3.69
No.2: (mt0 – mtx) – (mb0 – mbx)	2.41	3.38	3.85	3.62
D1: % Degradation	27	31	37	34
D2: % Degradation	22	31	35	33
D, Mean	25	31	36	34

Comments: * In the toxicity control 3.3 ± 0.2 mg/l test substance and 2.0 mg/l reference substance were used. The ThOD values were respectively COD values of these substances are shown in the tables above.

Validity criteria fulfilled:

yes

Interpretation of results:

under test conditions no biodegradation observed

Conclusions:

Within the test period of 28 days, a degradation of 1 % was determined for T-9601

T-9601 has to be classified as "Not Readily Biodegradable".

Executive summary:

Study conducted to procedure: Biodegradability - Closed Bottle Test Method according to Council Directive 92/69 EEC, Method C.4-E., in compliance with GLP. The test substance is suspended in a mineral medium, inoculated with a mixed population of aquatic microorganisms and incubated for 28 days under aerobic conditions in the dark at 20 ± 1°C.During this period, the biodegradation of the test substance is determined on the basis of the reduction of dissolved oxygen. Within the test period of 28 days, a degradation of 1% was determined for T-9601.

T-9601 has to be classified as "Not Readily Biodegradable".

Comments relevant to result: The validity criteria mentioned in the laboratories SOP number 2030-6600102-96 D were met.

In parallel preparations with the reference substance aniline a degradation of 66 % was achieved within 14 days.

Description of key information

Within the test period of 28 days, a degradation of 1 % was determined for T-9601.

Key value for chemical safety assessment

Biodegradation in water:

not biodegradable

Additional information

Study conducted to procedure: Biodegradability - Closed Bottle Test Method according to Council Directive 92/69 EEC, Method C.4-E., in compliance with GLP. The test substance is suspended in a mineral medium, inoculated with a mixed population of aquatic microorganisms and incubated for 28 days under aerobic conditions in the dark at 20 ± 1°C.During this period, the biodegradation of the test substance is determined on the basis of the reduction of dissolved oxygen. Within the test period of 28 days, a degradation of 1% was determined for T-9601.

T-9601 has to be classified as "Not Readily Biodegradable".

Comments relevant to result: The validity criteria mentioned in the laboratories SOP number 2030-6600102-96 D were met.

In parallel preparations with the reference substance aniline a degradation of 66 % was achieved within 14 days.