4-(1-oxo-2-propenyl)-morpholine

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:

on 10 March 1994

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 (Carbon and Ammonium Oxidation))

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

Batch number: 60513F07
Purity: 99.81%

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: The test substance was dissolved directly in test water without the aid of auxiliary solvents or dispersing agents.

Test organisms (species):

activated sludge of a predominantly domestic sewage

Details on inoculum:

- Preparation of inoculum for exposure:
A sample of activated sewage sludge was collected from sewage treatment farm. The sample was maintained at 20°C with continuous aeration and used within 24 hours of collection.

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

3 h

Hardness:

120-180 mg/L as CaCO3

Test temperature:

22°C

pH:

7.2-7.5

Dissolved oxygen:

2.5-6.5 mgO2/L

Nominal and measured concentrations:

Nominal concentration 100 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: glass beaker
- Type (delete if not applicable): open / closed
- Material, size, headspace, fill volume: 1 L
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: laboratory tap water, dechlorinated by passage through activated carbon and softened by reverse osmosis
- Particulate matter:

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod:
- Light intensity:
- Details on termination of incubation:

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
As each culture reached 3 hours contact time its pH was recorded and the rate of respiration measured using a Yellow springs dissolved oxygen meter and a magnetic stirrer. A 280 mL darkened glass BOD bottle was completely filled with the culture and sealed by the dissolved oxygen probe. The dissolved oxygen level was recorded for approximately 10 minutes. Separate measuring bottles were used for control, test and reference cultures to climinate the possibility of cross contamination.

Reference substance (positive control):

yes

Remarks:

3,5-Dichlorophenol

Key result

Duration:

3 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Validity criteria fulfilled:

yes

Conclusions:

The EC50 (respiration inhibition) for the substance with activated sludge has been determined as > 100 mg/L for the 3 hours contact time.

Executive summary:

The study was performed to assess the inhibitory effect of the substance on the respiration of activated sewage sludge, according to OECD Guideline 209 under GLP.

The EC50 (respiration inhibition) for the substance with activated sludge has been determined as > 100 mg/L for the 3 hours contact time.

Description of key information

The study was performed to assess the inhibitory effect of the substance on the respiration of activated sewage sludge, according to OECD Guideline 209 under GLP.
The EC50 (respiration inhibition) for the substance with activated sludge has been determined as > 100 mg/L for the 3 hours contact time.

Key value for chemical safety assessment

EC50 for microorganisms:

100 mg/L

EC10 or NOEC for microorganisms:

100 mg/L