1-hydroxy-4-[[4-[(methylsulphonyl)oxy]phenyl]amino]anthraquinone

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:

18 November to 14 December, 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:

Deion. water instead of dest. water for the stocksolution. 4 instead of 5 test concentrations and higher sludge weight after the washing procedure (Sludge concentrations in the test according to the guidelines)

GLP compliance:

yes

Specific details on test material used for the study:

Test substance
Code number: FAT - 36'038/F
En-Nr.: 409753.32
Purity 69.4 %
Appearance: solid
Solubility: inslouble
Storage: room temperature
Expiration date: 09/98

Analytical monitoring:

no

Details on sampling:

Not applicable

Vehicle:

yes

Details on test solutions:

Not applicable

Test organisms (species):

other: Activated sludge of a communal sewage treatment plant (Ara-BIRSIG Therwil)

Details on inoculum:

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:

not specified

Limit test:

no

Total exposure duration:

3 h

Post exposure observation period:

Not applicable

Hardness:

Not applicable

Test temperature:

21.0 °C

pH:

7.8 before start of the test

Dissolved oxygen:

Not applicable

Salinity:

Not applicable

Nominal and measured concentrations:

Nominal concentrations for FAT 36038/F: 320, 100 and 10 mg/l of the test substance
Nominal concentrations for reference substance: 32, 10 and 3.2 mg/l of the reference substance.

Details on test conditions:

- Sludge dry weight: 1.44 g/l
- Test volume: 100 ml
- Estimation technique: Aeration:O2 - consumption, measured with an oxygen sensitive electrode system: OXI DIGI 530 (SAV : 00 109) 0.1 - 0.2 l/min by pasteur-pipette

Reference substance (positive control):

yes

Remarks:

3,5-Dichlorophenol (Merck 821768).

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:

The test substance concentrations tested were 320, 100, 32 and 10 mg/L, at which the % inhibition observed were 0, 0, 0 and 1.71 %, respectively.

Results with reference substance (positive control):

The % inhibition observed were 84.00, 40.57 and 10.86 at 32,10 and 3.2 mg/L concentrations respectively. Hence, the IC50 (3 h) of the reference substance 3,5-Dichlorophenol: 13.0 mg/l.

Reported statistics and error estimates:

None

Validity criteria fulfilled:

yes

Conclusions:

The IC50 (3 h) of the test substance FAT 36038/F was determined to be >320.0 mg/L.

Executive summary:

The toxicity of FAT 36038/F to activated sludge was determined in a 3-hours respiration inhibition test according to the OECD Guideline No. 209, and to the EEC Method No. L 133/118. The test substance concentrations tested were 320, 100, 32 and 10 mg/L, at which the % inhibition observed were 0, 0, 0 and 1.71 %, respectively. Hence, the IC50 (3 h) of the test substance FAT - 36038/F was determined to be >320.0 mg/L.

Description of key information

The 3 h IC50 value for FAT 36038 was found to be >320 mg/L.

Key value for chemical safety assessment

EC50 for microorganisms:

320 mg/L

Additional information

The toxicity of FAT 36038/F to activated sludge was determined in a 3-hours respiration inhibition test according to the OECD Guideline No. 209, and to the EEC Method No. L 133/118. The test substance concentrations tested were 320, 100, 32 and 10 mg/L, at which the % inhibition observed were 0, 0, 0 and 1.71 %, respectively. Hence, the IC50 (3 h) of the test substance FAT - 36038/F was determined to be >320.0 mg/L. The supporting studies performed to determine the toxicity of FAT 36038/A, FAT 36038/C and FAT 36038/D to microorganisms according to Internal Method B-10 reported the IC50 greater than 300 mg/L in all the cases. Based on the data from these studies the 3 h IC50 of FAT 36038 can be considered to be greater than 320 mg/L.