Methyl tetrahydro-2-furancarboxylate

Toxicity to microorganisms

Administrative data

Endpoint:

activated sludge respiration inhibition testing

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Experimental phase: 30 April 1996

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: GLP, guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1996

Report date:

1996

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.11 (Biodegradation: Activated Sludge Respiration Inhibition Test)

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Methyl tetrahydro-2-furancarboxylate

EC Number:

420-670-1

EC Name:

Methyl tetrahydro-2-furancarboxylate

Cas Number:

37443-42-8

Molecular formula:

C6H10O3

IUPAC Name:

methyl oxolane-3-carboxylate

Details on test material:

Identity: Methfat
Chemical name: Methyl tetrahydro-2-furoate
Batch number: 17-5C03 (GLFC No.002)
Expiry: 7 November 1996
Purity: 99.4%
Appearance: Clear liquid
Storage conditions: In darkness at room temperature
Date received: 17 November 1995

Test organisms

Test organisms (species):

activated sludge of a predominantly domestic sewage

Details on inoculum:

- Type: A mixed population of activated sewage sludge micro-organisms
- Source: The aeration stage of the Anglian Water sewage treatment plant (Godmanchester) treating predominantly domestic sewage
- Preparation: A sample of activated sewage sludge was collected from the sewage treatment farm on 29 April 1996. The sample was maintained at 20 ± 2 °C with continuous aeration and used within 24 hours of collection. The suspended solids level of the sample was 4.2 g/l, consequently the inoculum was diluted by one third to obtain a suspended solids content of 2.8 g/l. The pH was 7.3, therefore no further adjustment of the inoculum was required.

Study design

Total exposure duration:

3 h

Test conditions

Test temperature:

20 ± 2 °C

pH:

7.3

Dissolved oxygen:

Between 8.5 and 3.0 mgO2/l

Nominal and measured concentrations:

Test substance: 100 mg/l in duplicate
Reference substance: 3.2, 10 and 32 mg/l

Details on test conditions:

TEST SYSTEM
- Aeration: 0.5 - 1 L/min with compressed air via a narrow bore glass tube

TEST MEDIUM / WATER PARAMETERS
Laboratory tap water, dechlorinated by passage through activated carbon and softened by reverse osmosis (hardness approximately 120- 180 mg/l as CaCO3, pH 7.5 ± 0.5).

Reference substance (positive control):

yes

Remarks:

3,5-Dichlorophenol, purity > 97%

Results and discussion

Effect concentrations

Duration:

3 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Results with reference substance (positive control):

EC50 (3h) = 9 mg/l.

Any other information on results incl. tables

The validation criteria for Control culture respiration and respiration inhibition by the reference substance, were fulfilled during this study.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The EC50 (respiration inhibition) values for Methfat with activated sewage sludge has been determined as > 100 mg/l for the 3 hour contact time.