Sodium bis[2-chloro-4-[(4,5-dihydro-3-methyl-5-oxo-1-phenyl-1H-pyrazol-4-yl)azo]-5-hydroxybenzenesulphonamidato(2-)]chromate(1-)

Toxicity to microorganisms

Link to relevant study record(s)

Reference

Endpoint:

toxicity to microorganisms

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1978

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

comparable to guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

other: In house SOP (method B.10) validated by Ciba which is comparable to standard guideline.

Principles of method if other than guideline:

The test was done before international testing guidelines habe been developed, therefore the test was done according to an internal standard operating procedure.

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

not specified

Test organisms (species):

other: Bacillus megatherium, Bacillus pumilus, Bacillus cereus, Bacillus Sphaericus, Mycobacterium rhodochrous, Moraxella sp., Pseudomonas putida, Pseudomonas stutzeri, Pseudomonas aeruginosa, Pseudomonas fluorescent, Escherichia coli and Pseudomonas Berlin 33/2

Test type:

not specified

Water media type:

not specified

Reference substance (positive control):

not specified

Dose descriptor:

IC50

Effect conc.:

> 300 mg/L

Remarks on result:

other: No further details are specified

No further details available.

Conclusions:

The IC50 of FAT 20028/B is greater than 300 mg/l.

Executive summary:

The IC₅₀ of FAT 20028/B is greater than 300 mg/l.

Description of key information

The study was carried out to determine the test substance concentration, which reduces the respiration of activated sludge by 50 % (IC₅₀).

Based on the study results the IC₅₀(3 h) of FAT - 20'028/B: 300 mg/l.

Another supporting study was carried out according the OECD guideline for Testing of Chemicals No.: 209, "Activated sludge, respiration Inhibition Test", April 4, 1984 and in compliance with the Good Laboratory Practice (GLP) Regulations of Switzerland. The toxicity of FAT - 20'028/D to activated sludge was determined in a 3-h respiration inhibition test. 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. Organisms used for the experiment were Activated sludge of a communal sewage treatment plant (ARA-Birsig Therwil). A reference substance ( 3,5 -Dichlorophenol (Merck 821768)), was used at 32, 10 and 3.2 mg/l.

Based on the study results the IC₅₀(3 h) of FAT - 20'028/D: >320 mg/l and IC₂₀(3 h) 115 mg/l. While IC₅₀(3 h) of the reference substance 3,5-Dichlorophenol: 11.0 mg/l.

Key value for chemical safety assessment

EC50 for microorganisms:

300 mg/L