1,4,7-trioxacyclotridecane-8,13-dione

Toxicity to microorganisms

Administrative data

Endpoint:

activated sludge respiration inhibition testing

Type of information:

experimental study

Adequacy of study:

key study

Study period:

1999-11-23

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: Guideline study, GLP.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1999

Report date:

1999

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 209 (Activated Sludge, Respiration Inhibition Test

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

2,3,7,8-tetrahydro-2,5,8-benzotrioxacycloundecine-1,9-dione

EC Number:

229-554-3

EC Name:

2,3,7,8-tetrahydro-2,5,8-benzotrioxacycloundecine-1,9-dione

Cas Number:

6607-34-7

Molecular formula:

C10H16O5

IUPAC Name:

1,4,7-Trioxacyclotridecane-8,13-dione

Details on test material:

- Name of test material (as cited in study report): Adipic acid, Cyclicester with diethylenglycol
- Analytical purity: ca. 90%
- Impurities (identity and concentrations): Diethylenglycol < 10% ; water< 2%
- Purity test date: Report of the sponsor of 18 Feb. 1999
- Lot/batch No.: B47

Sampling and analysis

Analytical monitoring:

no

Test solutions

Vehicle:

no

Test organisms

Test organisms (species):

activated sludge, domestic

Details on inoculum:

- Preparation of inoculum for exposure: The inoculum was washed, brought to a concentration of 5 g/l dry substance and aerated for 24 hours.
- Initial biomass concentration: 50 ml were added to a total volume of 250 ml to obtain a concentration of 1 g/I dry substance in the test.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

30 min

Test conditions

Test temperature:

20 ± 2°C

pH:

7.1-7.2 at test start, 7.3 at test end

Dissolved oxygen:

- Oxygen concentration during aeration: >2.5 mg/I
- Oxygen concentration immediately before measurement: >6.5 mg/I

Nominal and measured concentrations:

1000 mg/l, in addition a blanc control and a reference control were tested

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type (delete if not applicable): open
- Material, size, headspace, fill volume: glass, Erlenmeyer-flask (250 ml nominal), liquid volume: 250 ml
- Aeration: sparged with air
- No. of vessels per concentration (replicates; test substance, TS): 1
- No. of vessels per control (replicates; blanc, BC): 3
- No. of vessels per concentration (replicates; positive control, reference substance, RS): 3

TEST MEDIUM / WATER PARAMETERS
- Culture medium: OECD test medium

OTHER TEST CONDITIONS
- Adjustment of pH: no pH adjustments during test

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :
O2: on line measurement for 6 min
pH: at test start and test end

Reference substance (positive control):

yes

Remarks:

3.5-dichlorophenol (CAS 591-35-5)

Results and discussion

Effect concentrations

Duration:

30 min

Dose descriptor:

other: EC20

Effect conc.:

> 1 000 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

inhibition of total respiration

Remarks:

respiration rate

Results with reference substance (positive control):

- Results with reference substance valid? Yes
- Relevant effect levels: EC20 (30 min): 2.2 mg/L (nominal); EC50 (30 min): 6.5 mg/L (nominal); EC80 (30 min): 55 mg/L (nominal)

Any other information on results incl. tables

The EC20 in the activated sludge respiration inhibition test is >1000 mg/l. The inhibition of the degradation activity of activated sludge is not anticipated when introduced in appropriate low concentrations.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Remarks:

Deviation of blank controls < 15 %; EC50 of 3,5-dichlorophenol in the range of 5-30 mg/I