3-ethoxy-4,6-difluoro-7-(pentyloxy)dibenzo[b,d]furan

Biodegradation in water: screening tests

Administrative data

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Feb 05 - Mar 18, 2014

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2014

Report date:

2014

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.4-D (Determination of the "Ready" Biodegradability - Manometric Respirometry Test)

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

1

Reference substance name:

3-ethoxy-4,6-difluoro-7-(pentyloxy)dibenzo[b,d]furan

EC Number:

942-871-8

Cas Number:

1799569-89-3

Molecular formula:

C19H20F2O3

IUPAC Name:

3-ethoxy-4,6-difluoro-7-(pentyloxy)dibenzo[b,d]furan

Specific details on test material used for the study:

Name: Art. 201386 (B-2O-O5)
Batch No.: EF13004186

Empirical Formula C19H20F2O3
Molecular Weight: 334.36 g/mol
ThODNH4: 2.106 mg O2/mg test item
Colour: White
Physical Appearance: solid
Expiry Date: November 30, 2015
Storage: At room temperature (20°C ±5°C) , under dark and dry conditions

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure):activated sludge, micro organisms from a domestic waste water treatment plant- OriginMunicipal sewage treatment plant, Rossdorf, Germany-Conditioning:The activated sludge used for this study was washed by centrifugation and the supernatant liquid phase was decanted. The solid material was re-suspended in tap water and centrifuged again. This procedure was repeated twice. An aliquot of the final sludge suspension was weighed, dried and the ratio of wet sludge to its dry weight was determined. Based on this ratio, calculated aliquots of washed sludge suspension, corresponding to 3.5 g dry material per litre were mixed with test water.

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

102 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

According to guideline

Reference substance

Reference substance:

benzoic acid, sodium salt

Results and discussion

Test performance:

The reference item sodium benzoate was sufficiently degraded to 82% after 14 days and to 85% after 28 days of incubation.The validity criterion that the degradation should be > 60 % after 14 d was fulfilled.

% Degradation

Parameter:

% degradation (O2 consumption)

Value:

0

Sampling time:

28 d

Details on results:

Results of the Toxicity ControlIn the toxicity control containing both the test item and reference 27% biodegradation was noted within 14 days and 28% biodegradation was determined after 28 days of incubation.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

under test conditions no biodegradation observed

Conclusions:

The degradation rate of the test material did not reach 60 % within the 10-day window and after 28 days of incubation. Thus the test item is not readily biodegradable.

Executive summary:

The degradation rate of the test material did not reach 60 % within the 10 -day window and after 28 days of incubation. Thus the test item is not readily biodegradable.