1-Ethoxy-2,3-difluoro-4-(trans-4-propylcyclohexyl)-benzene

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Reference 1

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

supporting study

Study period:

Mar 17 - May 14, 2004

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 C (Ready Biodegradability: Modified MITI Test (I))

GLP compliance:

yes (incl. QA statement)

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
- Origin: Municipal sewage treatment plant
-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.

Duration of test (contact time):

28 d

Initial conc.:

100 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

According to guideline

Reference substance:

aniline

Key result

Parameter:

% degradation (O2 consumption)

Value:

1

Sampling time:

28 d

Results with reference substance:

The reference item (Aniline) was sufficiently degraded to 63 % after 14 days and to 72 % after 28 days of incubation. The validity criterion that the degradation should be > 60 % after 14 d was fulfilled.

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.

Executive summary:

Purpose

The test item was investigated for its ready biodegradability in a Manometric Respirometry Test over a period of 28 days. The biodegradation was followed by the oxygen uptake of the micro organisms during exposure. As a reference item aniline was tested simultaneously under the same conditions as the test item, and functioned as a procedure control. The GLP study was performed according to OECD TG 301C.

Result

Biodegradation of test item

After correction of the mean biochemical oxygen demand of the inoculum controls at the end of the 28 -day exposure period a degradation of 0% as found.

Biodegradation of aniline

The reference item was sufficiently degraded to 63 % after 14 days and to 72 % after 28 days of incubation, thus confirming the suitability of the used activated sludge inoculum.

Conclusion

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.

Reference 2

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Sep 04, 2002 - Oct 23, 2002

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Deviations:

no

GLP compliance:

yes

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, non-adapted

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 conc.:

104 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

OECD TG 301 F

Reference substance:

aniline

Key result

Parameter:

% degradation (O2 consumption)

Value:

-2

Sampling time:

28 d

Details on results:

Points of degradation plot (test substance):-2 % degradation after 28 d

Results with reference substance:

Points of degradation plot (reference substance): 85 % degradation after 14 d, 103 % after 28 d
Toxicity control: 42 % (14 d) and 51 (28 d)

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.

Executive summary:

Purpose

The test item was investigated for its ready biodegradability in a Manometric Respirometry Test over a period of 28 days. The biodegradation was followed by the oxygen uptake of the micro organisms during exposure. As a reference item aniline was tested simultaneously under the same conditions as the test item, and functioned as a procedure control. The GLP study was performed according to OECD TG 301F.

Result

Biodegradation of test item

After correction of the mean biochemical oxygen demand of the inoculum controls at the end of the 28 -day exposure period the degradation of -2 % was found.

Biodegradation of Aniline

The reference item was sufficiently degraded to 85 % after 14 days, and to 103 % after 28 days of incubation, thus confirming the suitability of the used activated sludge inoculum.

Biodegradation in the Toxicity Control

In the toxicity control containing both, the test item and the reference item, 42 % biodegradation was noted within 14 days and 51 % biodegradation was determined after 28 days of incubation. Thus, the test item can be assumed to be not inhibitory on the activated sludge micro organisms.

Conclusion

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.

Description of key information

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.

Key value for chemical safety assessment

Biodegradation in water:

not biodegradable

Type of water:

freshwater

Additional information

Key study (OECD 301F)

Purpose

The test item was investigated for its ready biodegradability in a Manometric Respirometry Test over a period of 28 days. The biodegradation was followed by the oxygen uptake of the micro organisms during exposure. As a reference item aniline was tested simultaneously under the same conditions as the test item, and functioned as a procedure control. The GLP study was performed according to OECD TG 301F.

Result

Biodegradation of test item

After correction of the mean biochemical oxygen demand of the inoculum controls at the end of the 28 -day exposure period the degradation of -2 % was found.

Biodegradation of Aniline

The reference item was sufficiently degraded to 85 % after 14 days, and to 103 % after 28 days of incubation, thus confirming the suitability of the used activated sludge inoculum.

Biodegradation in the Toxicity Control

In the toxicity control containing both, the test item and the reference item, 42 % biodegradation was noted within 14 days and 51 % biodegradation was determined after 28 days of incubation. Thus, the test item can be assumed to be not inhibitory on the activated sludge micro organisms.

Conclusion

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.

 

Supporting study (OECD 301C)

Purpose

The test item was investigated for its ready biodegradability in a Manometric Respirometry Test over a period of 28 days. The biodegradation was followed by the oxygen uptake of the micro organisms during exposure. As a reference item aniline was tested simultaneously under the same conditions as the test item, and functioned as a procedure control. The GLP study was performed according to OECD TG 301C. 

Result

Biodegradation of test item

After correction of the mean biochemical oxygen demand of the inoculum controls at the end of the 28 -day exposure period a degradation of 0% as found.

Biodegradation of aniline

The reference item was sufficiently degraded to 63 % after 14 days and to 72 % after 28 days of incubation, thus confirming the suitability of the used activated sludge inoculum.

Conclusion

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.