Disodium 5-[[4-[(2-bromo-1-oxoallyl)amino]-2-sulphonatophenyl]azo]-4-hydroxy-6-(methylamino)naphthalene-2-sulphonate

Toxicity to microorganisms

Link to relevant study record(s)

Reference

Endpoint:

activated sludge respiration inhibition testing

Type of information:

experimental study

Adequacy of study:

key study

Study period:

03 June 1993 to 24 June 1993

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test

Deviations:

yes

Remarks:

1. Deion, water instead of dest. water for the stock solution. 2 Preparation of the inoculum : higher sludge weight after the washing procedure. 3 4 instead of 5 test concentrations. 4. The temperature of the test was 22.2 °C instead of 20 ± 2 °C.

GLP compliance:

yes (incl. QA statement)

Remarks:

OECD Good Laboratory Regulations and the Procedures and Principles of Good Laboratory Praxis in Switzerland

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: 287380.26
- Expiration date of the lot/batch: Nov 1997

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: room temperature
- Solubility of the test substance in the solvent/vehicle: 50 g/l (in water)

Analytical monitoring:

yes

Details on sampling:

No Data

Vehicle:

not specified

Test organisms (species):

activated sludge

Details on inoculum:

Organism: Activated sludge of a communal sewage treatment plant (ARA-Birsig Therwil)
Sludge pretreatment: 3 times washing with tap water and addition of synthetic sewage (a day before the main test)

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

3 h

Post exposure observation period:

Study terminated after 3 h

Hardness:

No data

Test temperature:

22.2 °C

pH:

7.2 before the test beginning

Dissolved oxygen:

No data

Salinity:

No data

Nominal and measured concentrations:

320, 100, 32 and 10 mg/l of the test substance
32, 10 and 3.2 mg/l of the reference substance

Details on test conditions:

Temperature: 22.2 °C
Sludge dry weight: 1.56 g/l
Test volume: 100 ml
Test duration: 3h
Estimation technique: O2 - consumption, measured with an oxygen sensitive electrode system: OXI DIGI 530 (SAV : 00 109)
Aeration: 0.1 - 0.2 l/min by Pasteur-pipette
pH of sludge: 7.2 before the test beginning

Reference substance (positive control):

yes

Remarks:

3,5-Dichlorophenol

Duration:

3 h

Dose descriptor:

IC50

Effect conc.:

> 320 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Details on results:

Test substance:
The IC50 (3 h) of the test substance FAT - 92354/A: >320.0 mg/l.

Results with reference substance (positive control):

The IC50 (3 h) of the reference substance 3,5-Dichlorophenol: 7.0 mg/l.

Validity criteria fulfilled:

yes

Conclusions:

The IC50 (3 h) of the test substance (FAT 92354/A) was found to be >320.0 mg/l.

Executive summary:

The toxicity of FAT 92354/A to activated sludge was determined in a 3-h respiration inhibition test according to the OECD Guideline 209, and to the EG Method Nr.L 133/118. The test was performed in compliance with the Good Laboratory Practice (GLP) Regulations of Switzerland. The test substance concentrations tested were 320,100, 32 and 10 mg/l. The reference substance 3,5-Dichlorophenol was tested in concentrations of 32,10 and 3.2 mg/l. Based on the test results, IC50 (3 h) of the test substance (FAT 92354/A) was >320.0 mg/l while for the reference substance 3,5-Dichlorophenol, it was 7.0 mg/l.

Description of key information

The IC50 (3 h) of the test substance (FAT 92354/A) was >320.0 mg/l.

Key value for chemical safety assessment

EC50 for microorganisms:

320 mg/L

Additional information

The toxicity of FAT 92354/A to activated sludge was determined in a 3-h respiration inhibition test according to the OECD Guideline 209, and to the EG Method Nr.L 133/118. The test was performed in compliance with the Good Laboratory Practice (GLP) Regulations of Switzerland. The test substance concentrations tested were 320,100, 32 and 10 mg/l. The reference substance 3,5-Dichlorophenol was tested in concentrations of 32,10 and 3.2 mg/l. Based on the test results, IC50 (3 h) of the test substance (FAT 92354/A) was >320.0 mg/l while for the reference substance 3,5-Dichlorophenol, it was 7.0 mg/l.