[2-[[4-[(2-chloro-4-nitrophenyl)azo]phenyl]ethylamino]ethyl](2-hydroxypropyl)dimethylammonium chloride

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

biodegradation in water: inherent biodegradability

Type of information:

experimental study

Adequacy of study:

disregarded due to major methodological deficiencies

Study period:

1994-10-12 to 1994-10-19

Reliability:

3 (not reliable)

Rationale for reliability incl. deficiencies:

significant methodological deficiencies

Qualifier:

according to guideline

Guideline:

OECD Guideline 302 B (Inherent biodegradability: Zahn-Wellens/EMPA Test)

Version / remarks:

August 1989

GLP compliance:

no

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge: sewage treatment plant Bürrig
- Sampling date: October 12, 1994
- Pretreatment: none
- Concentration of sludge: 1.0 g/L (dry solids)

Duration of test (contact time):

7 d

Initial conc.:

100 mg/L

Based on:

DOC

Parameter followed for biodegradation estimation:

DOC removal

Details on study design:

none reported

Reference substance:

aniline

Parameter:

% degradation (DOC removal)

Value:

63

Sampling time:

3 h

Remarks on result:

other:

Remarks:

The high elimination within the first 3 h of the experiment indicates removal through adsorption of the test substance. No adsorption control included in the experiment.

Parameter:

% degradation (DOC removal)

Value:

87

Sampling time:

7 d

Results with reference substance:

94 % degradation of aniline within 28 days.

Table 1: Test results

Time	Control DOC [mg/L]	Test substance DOC [mg/L]	Test substance – Control DOC [mg/L]	Degradation [%]
0 h	-	-	100	0
3 h	9	45	37	63
7 d	10	23	13	87

Validity criteria fulfilled:

no

Interpretation of results:

other:

Remarks:

The high elimination within the first 3 h of the experiment indicates removal through adsorption of the test substance. No adsorption control included in the experiment.

Conclusions:

No conclusion on biodegradation can be made.

Executive summary:

The inherent biodegradability of the test substance was investigated in accordance with OECD Guideline 302 B (Zahn-Wellens Test) using non-adapted domestic sludge. The initial test substance concentration was 100 mg DOC/L. Biodegradation was followed by measurement of DOC removal from the test vessels.

63 % elimination of DOC could be observed after 3 h. After 7 d 87% DOC have been removed.

The high elimination within the first 3 h of the experiment indicates removal through adsorption of the test substance. As no adsorption control was included in the experiment, no conclusions can be made on the actual elimination of the test substance through biodegradation. Therefore, the study is considered to have significant methodological deficiencies and to be not valid.

Reference 2

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1994-07-21 to 1994-08-18

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study without detailed documentation

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

Version 29/12/1992

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 301 D (Ready Biodegradability: Closed Bottle Test)

GLP compliance:

no

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge (adaptation not specified)

Details on inoculum:

- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): collected from effluent of a laboratory-scale unit receiving predominantly domestic sewage
- Date of sampling: 15/07/1994
- Pre-treatment: none
- Initial inoculum concentration: 5ml/L

Duration of test (contact time):

28 d

Initial conc.:

7.6 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

TEST CONDITIONS
- Test temperature: 20-21 °C
- Continuous darkness: yes

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

Reference substance:

aniline

Key result

Parameter:

% degradation (O2 consumption)

Value:

5

Sampling time:

28 d

Remarks on result:

other: not readily biodegradable

Parameter:

COD

Value:

1 050 mg O2/g test mat.

Results with reference substance:

66% degradation of aniline within 28 days.

Table 1: Biodegradation results with test item

Day	Depletion of dissolved c(O2) [mg O2/L]		Degradation [%]
	Test item	Blank control
7	0.75	0.45	4
14	0.70	0.35	4
21	1.05	0.35	9
28	0.90	0.50	5

 

Chemical oxygen demand (COD) of test item: 1050 mg O₂/g

Validity criteria fulfilled:

yes

Interpretation of results:

not readily biodegradable

Conclusions:

The test item is not readily biodegradable.

Executive summary:

The ready biodegradability of the test item was investigated in accordance with Method EU C.4-E (Determination of the "Ready" Biodegradability - Closed Bottle Test, Version 29.12.1992). The test substance was applied at an initial concentration of 7.6 mg/L. Aniline was used as positive control.

5 % test substance degradation could be observed within 28 d. The test item was proofed to be non-toxic to aquatic microorganisms at the applied concentration. The reference substance aniline was degraded by 66 % within 28 days. Thus, it can be concluded that the test item is not readily bioderadable.

Description of key information

The test item showed 5 % degradation within 28 days under the conditions of test method EU C.4-E (Determination of the "Ready" Biodegradability - Closed Bottle Test, Version 29.12.1992) and is thus considered to be not readily biodegradable.

63 % and 87 % elimination of the test substance (verified by DOC measurements) could be observed after 3h and 7 d, respectively, under the conditions of the OECD 302 B Test (Zahn-Wellens Test, Version August 1989). The high elimination within the first 3 h of the experiment indicates removal through adsorption of the test substance. As no adsorption control was included in the experiment, no conclusions can be made on the actual elimination of the test substance through biodegradation.

Based on the chemical structure of the test item, ready biodegradability is not expected.

Key value for chemical safety assessment

Biodegradation in water:

under test conditions no biodegradation observed