1,2-dihydro-6-hydroxy-1,4-dimethyl-2-oxo-5-[[3-[(phenylsulphonyl)oxy]phenyl]azo]nicotinonitrile

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Endpoint:

biodegradation in water: inherent biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

10 March 1999 to 07 April 1999

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

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

Deviations:

not specified

GLP compliance:

no

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Code number: FAT 93460/A
- Source and batch No.of test material: EN 037098A7
- Expiration date of the batch: November 2003

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: room temperature

OTHER SPECIFICS:
Appearance: yellow, solid

Oxygen conditions:

not specified

Inoculum or test system:

activated sludge, industrial (adaptation not specified)

Details on inoculum:

- Sludge: 100 mg/L suspended solids
- Waste water plant: ARA - PRO RHENO Basel communal

Duration of test (contact time):

28 d

Initial conc.:

30 mg/L

Based on:

ThOD/L

Parameter followed for biodegradation estimation:

O2 consumption

Reference substance:

not specified

Key result

Parameter:

% degradation (O2 consumption)

Value:

0

Sampling time:

28 d

Parameter:

BOD5

Value:

0 mg O2/g test mat.

Results with reference substance:

90 % Biodegradation was observed after 14 days.

DAYS	BIODEGRADATION in%
	TEST SUBSTANCE			REFERENCE SUBSTANCE
	Flask 4	Flask 5	Mean	Flask 2	Flask 3	Mean
2	4.4	6.6	6	63.5	62.3	63
4	0.0	2.2	1	77.8	77.8	78
5	-11.0	-4.4	0	80.8	80.8	81
6	-11.0	0.0	0	85.6	84.4	85
7	-11.0	0.0	0	86.8	86.8	87
8	-15.5	-4.4	0	86.8	86.8	87
10	-24.3	-11.0	0	86.8	86.8	87
12	-24.3	-11.0	0	89.2	89.2	89
14	-24.3	-11.0	0	90.4	90.4	90
16	-28.7	-15.5	0	90.4	90.4	90
18	-28.7	-15.5	0	90.4	91.6	91
20	-28.7	-15.5	0	90.4	91.6	91
22	-35.3	-22.1	0	89.8	91.0	90
24	-35.3	-17.7	0	89.8	92.2	91
26	-35.3	-17.7	0	91.0	92.2	92
28	-35.3	-13.2	0	91.0	93.4	92

Validity criteria fulfilled:

yes

Interpretation of results:

not inherently biodegradable

Conclusions:

Mean value of the biodegradation of FAT 93460/A after 28 days was 0 and the biochemical oxygen demand (BOD5) after 5 days was: 0 mg O2/g.

Executive summary:

The inherent biodegradability of the test substance was evaluated in a modified MITI (II) test conducted according to OECD Guideline 302C. The sludge used for the test had 100 mg/L suspended solids and a theoretical oxygen demand of 45.30 mg O2/L as initial concentration. The observation was carried out for 28 days. Based on the findings of the study, the mean value of the biodegradation of FAT 93460/A after 28 days was 0 and the biochemical oxygen demand (BOD5) after 5 days was: 0 mg O2/g.

Description of key information

The inherent biodegradability of the test substance was evaluated in a modified MITI (II) test conducted according to OECD Guideline 302C. The sludge used for the test had 100 mg/L suspended solids and a theoretical oxygen demand of 45.30 mg O2/L as initial concentration. The observation was carried out for 28 days. Based on the findings of the study, the mean value of the biodegradation of FAT 93460/A after 28 days was 0 and the biochemical oxygen demand (BOD5) after 5 days was: 0 mg O2/g.

Key value for chemical safety assessment

Biodegradation in water:

not biodegradable

Type of water:

freshwater