4-trans-Methoxy-4-trans-propyl-[1,1-bicyclohexyl]

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:

Sep 08, 2010 - Oct 16, 2010

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- OriginMunicipal 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

Preliminary study:

The biodegradation in % was calculated based on the ThOD of the test item.

Test performance:

The reference item (Aniline) was sufficiently degraded to 77 % after 14 days and to 78 % after 28 days of incubation.The validity criterion that the degradation should be > 60 % after 14 d was fulfilled.

Key result

Parameter:

% degradation (O2 consumption)

Value:

0

Sampling time:

28 d

Results with reference substance:

Comments: the degradation of the test item did not reach 60 % within the 10-day window and after 28 days of incubation. Therefore, the test item is not considered to be readily biodegradable.

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 77 % after 14 days and to 78 % 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:

Dec 12, 2006 - Feb 26, 2007

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)

Qualifier:

according to guideline

Guideline:

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

GLP compliance:

yes (incl. QA statement)

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

Source / origin: Activated sludge, microorganisms from a domestic waste water treatment plant was supplied by the sewage 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 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/L were mixed with test water and then aerated until use.

Duration of test (contact time):

28 d

Initial conc.:

103 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

TEST CONDITIONS
- Composition of medium: Reconstituted Test Water according to OECD 301
- Additional substrate: no
- Test temperature: 22 °C
- pH: 7.6 (measured at the start of the test)
7.7 - 7.9 (measured at the end of the test)
- pH adjusted: no
- Aeration of dilution water: yes
- Continuous darkness: yes
- surrounding: Climate chamber

TEST SYSTEM
- Culturing apparatus: Manometric Test System with test flasks containing a volume of 500 mL
- Number of culture flasks/concentration: 2
- Measuring equipment: BSB/BOD-Sensor-System, Aqualytic, 63231 Neu Isenburg, Germany
- Test performed in closed vessels due to significant volatility of test substance: yes

CONTROL AND BLANK SYSTEM
- Inoculum blank: inoculum and test medium
- Procedure control: reference item, inoculum and test medium
- Abiotic sterile control: test item and test medium
- Toxicity control: test item, reference item, inoculum and test medium

Reference substance:

benzoic acid, sodium salt

Key result

Parameter:

% degradation (O2 consumption)

Value:

0

Sampling time:

28 d

Details on results:

Under the test conditions, the degradation rate of the test item did not reach 60 % within the 10-day window and after 28 days of incubation. In the toxicity containing both, the test item and the reference item 28 % biodegradation was noted within 14 days and 32 % biodegradation was determined after 28 days of incubation.

Results with reference substance:

The reference item sodium benzoate was sufficiently degraded to 87 % after 14 days and to 90 % after 28 days of incubation.

Table 1: Percentage Biodegradation of Test Item, of Sodium Benzoate and of the Toxicity Control

Time (Days)	Percentage Biodegradation^1
	Test Item		Sodium benzoate	Toxicity control^2
	Flask 1 [%]	Flask 2 [%]	Flask 5 [%]	Flask 7 [%]
1	0	0	28	7
2	-2	-2	40	14
3	-2	-2	51	18
4	-2	-2	61	22
5	-3	-3	69	23
6	-3	-3	74	24
7	-2	-3	76	25
8	-2	-3	79	25
9	-2	-3	81	26
10	-2	-3	83	27
11	-2	-2	84	27
12	-2	-2	85	27
13	-2 -	2	87	28
14	-1	-1	87	28
15	-1	-1	87	28
16	-2	-1	86	28
17	-1	-1	86	29
18	0	0	87	29
19	0	0	87	29
20	1	1	90	30
21	1	1	90	30
22	1	1	89	31
23	2	2	90	31
24	1	2	90	31
25	1	2	90	31
26	1	2	89	31
27	1	2	89	31
28	1	2	90	32

¹ based on ThOD_NH4

ThOD_NH4 of test item: 3.087 mg/mg

ThOD_NH4/ ThOD_NO3 of sodium benzoate: 1.666 mg/mg

Validity criteria fulfilled:

yes

Interpretation of results:

not readily biodegradable

Conclusions:

After correction of the mean biochemical oxygen demand of the inoculum controls at the end of the 28 -day exposure period the degradation of 0 % was found. 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 test item was investigated for its ready biodegradability in a Manometric Respirometry Test according to OECD 301 F over a period of 28 days. The biodegradation was followed by the oxygen uptake of the microorganisms during exposure. As a reference item sodium benzoate was tested simultaneously under the same conditions as the test item, and functioned as a procedure control. All validity criteria were fulfilled. After correction of the mean biochemical oxygen demand of the inoculum controls at the end of the 28 -day exposure period the degradation of 0 % was found. The reference item was sufficiently degraded to 87 % after 14 days, and to 90 % after 28 days of incubation, thus confirming the suitability of the used activated sludge inoculum. In the toxicity control containing both, the test item and the reference item, 28 % biodegradation was noted within 14 days and 32 % biodegradation was determined after 28 days of incubation. Thus, the test item can be assumed to be not inhibitory on the activated sludge microorganisms. In 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

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

The test item was investigated for its ready biodegradability in a Manometric Respirometry Test according to OECD 301 F over a period of 28 days. The biodegradation was followed by the oxygen uptake of the microorganisms during exposure. As a reference item sodium benzoate was tested simultaneously under the same conditions as the test item, and functioned as a procedure control. All validity criteria were fulfilled. After correction of the mean biochemical oxygen demand of the inoculum controls at the end of the 28 -day exposure period the degradation of 0 % was found. The reference item was sufficiently degraded to 87 % after 14 days, and to 90 % after 28 days of incubation, thus confirming the suitability of the used activated sludge inoculum. In the toxicity control containing both, the test item and the reference item, 28 % biodegradation was noted within 14 days and 32 % biodegradation was determined after 28 days of incubation. Thus, the test item can be assumed to be not inhibitory on the activated sludge microorganisms. In 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.