Ethylene 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:

02 April 2001 - 03 April 2001

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test

Deviations:

no

Qualifier:

according to guideline

Guideline:

ISO 8192 (Water quality - Test for inhibition of oxygen consumption by activated sludge for carbonaceous and ammonium oxidation)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Batch number: From continuous production
- Substance number: 00/0884-1
- Date of production: EC-Kampagene 10/2000
- Product number: 81266
- Aggeregate state: solid
- Colour: colourless-yellowish
- Homogenity: yes at 50°C
- CAS n°: 96-49-1
- Expiry date: unknown

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Instability against: hygroscopic
- Storage condition: Under N2, ambient

Analytical monitoring:

no

Details on sampling:

not applicable

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
Preparation of the stock solution of the test substance : none
Synthetic medium: 8 ml/vessel 100-fold concentrated OECD medium

Test organisms (species):

activated sludge of a predominantly domestic sewage

Details on inoculum:

- Name and location of sewage treatment plant where inoculum was collected: Activated sludge from laboratory wastewater plant treating municipal sewage.
- Preparation of inoculum for exposure: The inoculum was washed, brought to a concentration of 5 g/L dry substance and aerated during the night. 50 mL were added to a total volume of 250 mL to obtain a concentration of 1 g/L dry substance in the test.
- Initial biomass concentration: Concentration of dry substance: 1 g/L.

Test type:

static

Total exposure duration:

30 min

Hardness:

not reported

Test temperature:

20 ± 2 °C

pH:

Test substance:
before adding the inoculum: 4.9
after 30 min of incubation period: 7.3

Reference substance:
before adding the inoculum: 4.6
after 30 min of incubation period: 7.7

Blank control:
before adding the inoculum before correction: 6.8

Dissolved oxygen:

Oxygen concentration during aeration: > 2.5 mg/l
Oxygen concentration immediately before measurement: > 6.5 mg/l
Duration of the measurement of oxygen consumption: 8-10 mins

Nominal and measured concentrations:

Reference substnance: 1, 10 and 100 mg/L
Blank control and reference: 1000 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel:: Erlenmeyer
- Test volume: 250 ml

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Synthetic medium: 8 mL/vessel 100-fold concentrated OECD medium

Reference substance (positive control):

yes

Remarks:

3,5-dichlorophenol

Key result

Duration:

30 min

Dose descriptor:

EC50

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Details on results:

- 30 min EC20 > 1000 mg/L
- 30 min EC80 > 1000 mg/L

Results with reference substance (positive control):

Results with reference substance valid? yes
- Other:
EC20: ca. 5 mg/L
EC50: ca. 28 mg/L
EC80: > 100 mg/L
Highest concentration test: 100 mg/L

Validity criteria fulfilled:

yes

Remarks:

See section overall remarks

Conclusions:

The nominal values for EC20, EC50 and EC80 for ethylene carbonate after 30 mins of incubation were all > 1000 mg/L.

Description of key information

An activated sludge respiration inhibition study of good quality was performed by Bachner (2001). The study was performed at test concentration of 1000 mg/L. Activated sewage sludge from laboratory wastewater plant treating municipal sewage was used in the study. The rate of respiration was determined after 30 minutes contact time. No inhibition was observed at nominal concentrations up to 1000 mg/L. The EC50 value after 30 minutes of incubation was > 1000 mg/L.