4-[4-trans-(3,4-Difluorophenyl)-cyclohexyl]-cyclohexanone

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:

March 14, 2001 - April 11, 2001

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Reliability 1

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2001

Report date:

2001

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

1992

Test guideline 2

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

1992

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

4-[4-trans-(3,4-Difluorophenyl)-cyclohexyl]-cyclohexanone

EC Number:

604-593-2

Cas Number:

147622-85-3

Molecular formula:

C18 H22 F2 O

IUPAC Name:

4-[4-trans-(3,4-Difluorophenyl)-cyclohexyl]-cyclohexanone

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic (adaptation not specified)

Remarks:

Source: stp Groß-Zimmern, Germany

Details on inoculum:

The activated sludge used for this study was washed by centrifugation and the supernatant liquid phase was decanted. The solid material was resuspended in tap water and again centrifuged. 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 1.5 g dry material per litre were mixed with test water and then aerated until use.

Duration of test (contact time):

28 d

Initial test substance concentration

Initial test substance concentration 1

Initial conc.:

100 mg/L

Based on:

test mat.

Initial test substance concentration 2

Initial conc.:

101.6 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

OECD TG 301 F

Reference substance

Reference substance:

aniline

Remarks:

100 mg/L

Results and discussion

% Degradation

Key result

Parameter:

% degradation (O2 consumption)

Value:

>= 0 - <= 1

Sampling time:

28 d

Details on results:

Points of degradation plot (test substance): 0-1% degradation after 28 d

BOD5 / COD results

Results with reference substance:

Points of degradation plot (reference substance): 90% degradation after 14 days, 93% degradation after 28 days

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

not readily biodegradable

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.