2-[(1-amino-9,10-dihydro-4-hydroxy-9,10-dioxo-2-anthryl)oxy]ethyl phenyl carbonate

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:

10 February 2000 to 01 March 2000

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:

During the preparation of the inoculum the sludge weight after the washing procedure was higher as recommended. The sludge concentrations in the test were according to the guidelines.

GLP compliance:

no

Analytical monitoring:

no

Details on sampling:

- Test Concentrations: 1, 10 and 100 mg/l of the test substance.
The test substance was not soluble in the test medium. Therefore it was given directly into the test system without preparation of a stock solution.

Vehicle:

no

Details on test solutions:

A synthetic sewage feed was made by dissolving the following amounts of substances in 1 litre of deionized water:
-16.0 g peptone.
-11.0 g meat extract.
- 3.0 g urea.
- 0.7g NaCI.
- 0.4 g CaCI2 x 2H20.
- 0.2 g MgS04x 7H20.
- 2.8 g K2HP04.

Test organisms (species):

activated sludge

Details on inoculum:

-Test system: Activated sludge of a communal sewage treatment plant (ARA Therwil) collected on February 09, 2000.

-Sludge pre-treatment: The inoculum was preparated 1 day prior to the experimental start. The freshly collected activated sludge was washed 3 times
with tap water. Subsequently the sludge was aerated. A sample of the activated sludge was taken to determine the dry weight of the suspended solids.
The final concentration of the inoculum was adjusted to about 5.0 g/l suspended solids. For the storage overnight synthetic sewage feed was added depending on the sludge concentration.

Test type:

static

Water media type:

not specified

Limit test:

no

Total exposure duration:

3 h

Post exposure observation period:

Test terminated after 3h.

Hardness:

No data

Test temperature:

21 °C

pH:

The pH-values of the content of the test vessels was measured at the end of the test.
- Control (C1 and C2): 7.8 and 8.0.
- at 1, 10 and 100 mg/l : 8.0.

Dissolved oxygen:

No data

Salinity:

No data

Nominal and measured concentrations:

test substance in mg/l (nominal concentrations): 1, 10 and 100.

Details on test conditions:

-Temperature: 21 °C
-Sludge dry weight: 1.5 g/l suspended solids.
-Test volume: 100 ml
-Aeration: 0.1-0.2l/min by Pasteur pipette.

Test medium:
-16.0 g peptone
-11.0 g meat extract
- 3.0 g urea
- 0.7g NaCI
- 0.4 g CaCI2 • 2H20
- 0.2 g MgS04 • 7H20
- 2.8 g K2HP04

Reference substance (positive control):

no

Key result

Duration:

3 h

Dose descriptor:

IC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Duration:

3 h

Dose descriptor:

other: IC20

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Reported statistics and error estimates:

The respiration rate of each test concentration was calculated as a percentage of the mean of the two control respiration rates. Since the EC50-value was >100 mg/l, no statistical evaluation was carried out.

Validity criteria fulfilled:

yes

Remarks:

the respiration rates of the two controls were within 15 % of each other.

Conclusions:

In conclusion, the IC50 of FAT 93504/A was found to be greater than 100 mg/l.

Executive summary:

This study was performed to determine the IC50 (concentration of the test substance which inhibits the respiration activity of the activated sludge by 50 %), of FAT 93504/A.

This test was performed according to the OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test).

The test system is activated sludge obtained from a communal waste water treatment plant.

The duration of the test is 3 hours at 21 °C.

This is a static test , slowly aerated and the test volume is 100 ml.

The test was done at test concentrations of 1, 10, and 100 mg/l of the test substance.

In conclusion, the IC50 of the test substance after 3 hours is greater than 100 mg/l.

The IC20 of the test substance after 3 hours is greater than 100 mg/l.

Description of key information

The IC50 of FAT 93504/A was found to be greater than 100 mg/l.

Key value for chemical safety assessment

EC50 for microorganisms:

100 mg/L

Additional information

This study was performed to determine the IC50 (concentration of the test substance which inhibits the respiration activity of the activated sludge by 50 %), of FAT 93504/A. following the OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test). The IC50 of the test substance after 3 hours is greater than 100 mg/l.