2-methyl-1,4-phenylene-bis[4-(6-acryloyloxyhexyloxy)benzoate]

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:

key study

Study period:

22 Dec 1995 - 19 Jan 1996

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test)

Version / remarks:

1993

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.4-C (Determination of the "Ready" Biodegradability - Carbon Dioxide Evolution Test)

Version / remarks:

July 1992

Deviations:

no

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: activated sludge from a laboratory wastewater treatment plant operated with municipal and synthetic sewage
- Preparation of inoculum for exposure: Inoculum was pre-aerated one day before the start of the test.
- Concentration of sludge: 30 mg/L

Duration of test (contact time):

28 d

Initial conc.:

20 mg/L

Based on:

TOC

Initial conc.:

30 mg/L

Based on:

test mat.

Parameter followed for biodegradation estimation:

CO2 evolution

Details on study design:

TEST CONDITIONS
- Composition of medium: defined inorganic medium
- Test temperature: room temperature
- Aeration of dilution water: Yes
- Suspended solids concentration: 30 mg/L

TEST SYSTEM
- Number of culture flasks/concentration: 2 (blank, reference control and toxicity control), 4 (test substance)

CONTROL AND BLANK SYSTEM
- Inoculum blank: deionized water + inorganic medium + inoculum
- Abiotic sterile control: no
- Toxicity control: reference control + test substance
- Reference control: Inoculum blank + reference substance

Reference substance:

aniline

Key result

Parameter:

% degradation (CO2 evolution)

Value:

>= 0 - <= 10

Sampling time:

28 d

Details on results:

The degradation in the toxicity control achieved 42% after 14 days. After 28 days the biodegradation was 48%. The validity criterion (biodegradation > 25% after 14 days) that the test item should not inhibit the biodegradation of the reference item was fulfilled.

Results with reference substance:

Degradation was 80-90 % CO2/ThCO2 after 14 days. The validity criterion that the degradation should be > 60% after 14 days was fulfilled.

Validity criteria fulfilled:

yes

Interpretation of results:

not readily biodegradable

Conclusions:

In this CO2 Evolution Test, the biodegradation after 28 days was < 10%. Thus, the test item is not considered to be readily biodegradable.

Executive summary:

The biodegradability of the test item was determined by measurement of the carbon dioxide production in the CO2 -Evolution Test according to OECD Guideline 301 B and EU Method C.4 -C under GLP conditions. Mixtures of the test substance, a defined inorganic medium and a non pre-adapted inoculum were incubated and aerated at room temperature up to 28 days in this static method.

The degradation in the toxicity control achieved 42% after 14 days. After 28 days the biodegradation was 48%. The validity criterion (biodegradation > 25% after 14 days) that the test item should not inhibit the biodegradation of the reference item was fulfilled . Degradation in the reference control was 80-90 % CO2/ThCO2 after 14 days. The validity criterion that the degradation should be > 60% after 14 days was fulfilled. The validity criteria of the Guideline are fulfilled.

Both test item replicates did not reach the 10% level within the 28 day period of the study. Thus, the test item is not readily biodegrdable under the test conditions chosen.

Reference 2

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

July 04, 2006 - August 11, 2006

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

1992

Deviations:

no

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

1992

Deviations:

no

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: sewage plant Rossdorf
- Preparation of inoculum for exposure: 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 per litre were mixed with test water and then aerated until use.
The washed activated sludge was aerated overnight and used the following day for the experiment.
- Concentration of sludge: 1.5 g/L on dry matter base (final concentration: 30 mg/L)

Duration of test (contact time):

28 d

Initial conc.:

25 other: mg

Based on:

test mat.

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

TEST CONDITIONS
- Composition of medium: according to OECD Guideline 301 F
- Test temperature: 22°C
- pH: 7.6 (measured at the start of the test), 7.6 - 7.8 (measured at the end of the test)
- pH adjusted: no
- Suspended solids concentration: stock suspension of 1.5 g/L (final concentration: 30 mg/L)
- Continuous darkness: yes

TEST SYSTEM
- Culturing apparatus: flasks containing a volume of 500 mL
- Number of culture flasks/concentration: 2 (test item, inoculum control); 1 (procedure control, abiotic control and toxicity control)
- Method used to create aerobic conditions: The washed activated sludge was aerated overnight and used the following day for the experiment.
- Measuring equipment: The change of pressure in the flasks was measured by means of a manometric method (BSB/BOD-Sensor-System).
- Details of trap for CO2: Evolved carbon dioxide was absorbed in an aqueous solution (45%) of potassium hydroxide.

CONTROL AND BLANK SYSTEM
- Inoculum blank: activated sludge + dilution water
- Abiotic sterile control: test item + dilution water
- Toxicity control: test item + positive control + activated sludge + dilution water
- Positive control: reference item + activated sludge + dilution water

Reference substance:

benzoic acid, sodium salt

Key result

Parameter:

% degradation (O2 consumption)

Value:

5

Sampling time:

28 d

Details on results:

In the toxicity control containing both, the test item and the reference item sodium benzoate, 41 % biodegradation was noted within 14 days and 42 % biodegradation was determined after 28 days of incubation. Thus, the test item can be assumed to be not inhibitory on the activated sludge microorganisms because degradation was > 25 % within 14 days.
The oxygen demand in the abiotic control was 0 mg/L

Results with reference substance:

The reference item sodium benzoate was sufficiently degraded to 99 % after 14 days, and to 105 % after 28 days of incubation.

Validity criteria fulfilled:

yes

Interpretation of results:

not readily biodegradable

Conclusions:

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

Executive summary:

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 sodium benzoate was tested simultaneously under the same conditions as the test item, and functioned as a procedure control.

The reference item sodium benzoate was sufficiently degraded to 99 % after 14 days, and to 105 % after 28 days of incubation (ThODNH4).

In the toxicity control containing both, the test item and the reference item sodium benzoate, 41 % biodegradation was noted within 14 days and 42 % biodegradation was determined after 28 days of incubation. Thus, the test item can be assumed not to be inhibitory on the activated sludge microorganisms.

The study is valid.

The test item was not degraded after 28 days of incubation. The degradation rate of the test item did not reach 60 % within the 10-day window and after 28 days of incubation. The test item is considered not to be readily biodegradable.

Description of key information

In the CO2 Evolution Test (OECD 301B), the biodegradation after 28 days was < 10%. Thus, the test item is not considered to be readily biodegradable.

In the Manometric Respiratory Test (OECD 301F), the degradation rate of the test item was 5% and thus did not reach 60 % within the 10-day window and after 28 days of incubation. The test item is considered not to be readily biodegradable.

Key value for chemical safety assessment

Biodegradation in water:

under test conditions no biodegradation observed

Type of water:

freshwater

Additional information

The ready biodegradability of the test item was investigated in a CO2 Evolution Test (OECD 301B) and in a Manometric Respiratory Test (OECD 301F).

In the CO2 Evolution Test (OECD 301B), the biodegradation after 28 days was < 10%. In the Manometric Respiratory Test (OECD 301F), the degradation rate of the test item was 5% and thus did not reach 60 % within the 10-day window and after 28 days of incubation. In both tests, the validity criteria of the Guideline were fulfilled.