hexasodium 4-[3-(2-bromoprop-2-enamido)benzamido]-6-[(E)-2-[5-(2,3-dibromopropanamido)-2-sulfophenyl]diazen-1-yl]-5-hydroxynaphthalene-1,7-disulfonate 6-[(E)-2-[5-(2-bromoprop-2-enamido)-2-sulfophenyl]diazen-1-yl]-4-[3-(2-bromoprop-2-enamido)benzamido]-5-hydroxynaphthalene-1,7-disulfonate

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:

1993

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

None

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 (Sludge concentrations in the test according to the guidelines); 3. 4 instead of 5 test concentrations

Principles of method if other than guideline:

Guideline followed

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Code number: FAT - 92'348/A,
EN - number: 279291.26,
Purity: ca. 100 %,
Appearance: solid,
Solubility: 100g/l (in water),
Storage: room temperature,
Expiration date: 9/97,
Safety: Test substance will, unless otherwise specified, be handled using safety precautions "Sicherheit im Labor von A - Z", SAV: 00 303.

Analytical monitoring:

no

Details on sampling:

None

Vehicle:

no

Details on test solutions:

None

Test organisms (species):

activated sludge, domestic

Details on inoculum:

Test system / Test organism:
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

Hardness:

no data

Test temperature:

20.8 °C

pH:

7.9 - 8.0

Dissolved oxygen:

No data

Salinity:

no data

Conductivity:

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: 20.8 °C
Sludge dry weight: 1.5g/l
Test volume: 100 ml
Test duration: 3 h
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: 7.9 before the test beginning

Reference substance (positive control):

yes

Remarks:

3,5-Dichlorophenol

Key result

Duration:

3 h

Dose descriptor:

IC50

Effect conc.:

> 320 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Results with reference substance (positive control):

The IC50 (3 h) of the reference substance 3,5-Dichlorophenol : 9.5 mg/l.

Table 1: Oxygen consumption test – test substance

Test substance (mg/l)	pH after 3 h	O2 consumption in cm	Time in cm	mg O2 pro min/l	% control	% inhibition
320	7.9	4.1	4.2	0.78	97.50	2.50
100	8.0	4.3	4.4	0.78	97.50	2.50
32	8.0	4.0	4.2	0.76	95.00	5.00
10	8.0	4.5	4.7	0.77	96.25	3.75

 

Table 2: Oxygen consumption test – reference substance

Test substance (mg/l)	pH after 3 h	O2 consumption in cm	Time in cm	mg O2 pro min/l	% control	% inhibition
32	8.2	1.0	5.6	0.14	17.50	82.50
10	8.1	2.5	5.1	0.39	48.75	51.25
3.2	8.0	3.9	4.6	0.68	85.00	15.00

Validity criteria fulfilled:

yes

Conclusions:

IC50 (3 h) of the test substance FAT - 92'348/A was determined to be > 320.0 mg/l.

Executive summary:

The toxicity of FAT - 92'348/A to activated sludge was detemiined in a 3-hours respiration inhibition test according to the GECO Guideline No. 209, and to the EG Method Nr.L 133/118.

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 findings of the study, IC50 (3 h) of the test substance FAT - 92'348/A was determined to be > 320.0 mg/l, while IC50 (3 h) of the reference substance 3,5-Dichlorophenol was determined to be 9.5 mg/l.

Description of key information

The IC50 (3 h) of the test substance FAT 92348/A was noted to be: >320.0 mg/l.

Key value for chemical safety assessment

EC50 for microorganisms:

320 mg/L

Additional information

The toxicity of FAT - 92'348/A to activated sludge was detemiined in a 3-hours respiration inhibition test according to the GECO Guideline No. 209, and to the EG Method Nr.L 133/118.

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 findings of the study, IC50 (3 h) of the test substance FAT - 92'348/A was determined to be > 320.0 mg/l, while IC50 (3 h) of the reference substance 3,5-Dichlorophenol was determined to be 9.5 mg/l.