Reaction mass of 2-dodecylhexadecyl methacrylate and 2-Tetradecyloctadecyl methacrylate

Biodegradation in water: screening tests

Link to relevant study record(s)

Reference

Endpoint:

biodegradation in water: ready biodegradability

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From 17 October to 14 November 2019

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)

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: Cambridge STW, Cowley Road, Cambridge
- Preparation of inoculum for exposure: Sieved to 850μm, settled, decanted and re-suspended using mineral media. Centrifuged at 4000rpm for 10 minutes discarding the supernatant, re-suspended and centrifuged again at 4000rpm for 10 minutes and discarding the supernatant. Dry sludge solids determination was conducted on the pellet produced.
- Concentration of sludge: 0.0299g/L dry sludge solids in test

Duration of test (contact time):

28 d

Initial conc.:

9.9 mg/L

Based on:

ThOD

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

TEST CONDITIONS
- Composition of medium: The mineral medium was prepared by the addition of mineral nutrient stock solutions to deionised water.
- Test temperature: 20.4 – 22.8°C
- pH: At test termination the pH of the reference replicates reached 8.73 and 8.88, the toxicity control also reached 9.07.
- pH adjusted: no

TEST SYSTEM
- Number of culture flasks/concentration: 2
- Measuring equipment: The BOD of the test solutions is monitored using the OXITOP® Control OC 110 controller in conjunction with the OXITOP® Control 12 measuring heads. All generated data is manipulated using the communication software ACHAT OC.

SAMPLING
Not applicable: The OXITOP® measuring heads recorded readings of biodegradation every 112 minutes for 28 days.

CONTROL AND BLANK SYSTEM
- Inoculum blank: Included
- Abiotic sterile control: Not included
- Toxicity control: Included

Reference substance:

acetic acid, sodium salt

Parameter:

% degradation (O2 consumption)

Value:

45

Sampling time:

7 d

Parameter:

% degradation (O2 consumption)

Value:

61

Sampling time:

14 d

Parameter:

% degradation (O2 consumption)

Value:

70

Sampling time:

21 d

Parameter:

% degradation (O2 consumption)

Value:

74

Sampling time:

28 d

Details on results:

Reaction Mass of 2-Propenoic acid, 2-methyl-, 2-dodecylhexadecyl ester and 2-Propenoic acid, 2-methyl-, 2-tetradecyloctadecyl ester (EC 946-978-0) did not achieve the 10-day window since a degradation > 60% (relative to the ThOD value) was not reached until Day 13

Parameter:

ThOD

Value:

3 029 mg O2/g test mat.

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable, but failing 10-day window

Conclusions:

Reaction mass of 2-Propenoic acid, 2-methyl-, 2-dodecylhexadecyl ester and 2-Propenoic acid, 2-methyl-, 2-tetradecyloctadecyl ester (EC 946-978-0) was degraded at 74% after 28 days but failed to meet the 10-day window.

Executive summary:

The ready biodegradability Reaction mass of 2-Propenoic acid, 2-methyl-, 2-dodecylhexadecyl ester and 2-Propenoic acid, 2-methyl-, 2-tetradecyloctadecyl ester (EC 946-978-0) was evaluated during a GLP-compliant study performed in accordance with the OECD Testing Guideline 301F (Manometric Respirometry).

The test was performed in closed vessels containing a known concentration of test item in inoculated medium incubated at constant temperature for 28 days. The percent of biodegradation of the test item was calculated based on the Theoretical Oxygen Demand (ThOD) of 3029 mg O2/g test item calculated for the test substance. Oxygen consumption was evaluated through the study.

Sodium acetate was used as reference substance.

The mean biodegradation value of the test item at the end of the test period, on Day 28, was 74% of the ThOD.

Validation criteria were met. A toxicity control indicated that the test substance had no inhibitory effect on the activity of activated sludge microorganisms at the tested concentration of 9.9 mg/L.

Reaction mass of 2-Propenoic acid, 2-methyl-, 2-dodecylhexadecyl ester and 2-Propenoic acid, 2-methyl-, 2-tetradecyloctadecyl ester (EC 946-978-0) was found to be readily biodegradable under the test conditions within 28 days, but failed to meet the 10-day window.

Description of key information

The ready biodegradability Reaction mass of 2-Propenoic acid, 2-methyl-, 2-dodecylhexadecyl ester and 2-Propenoic acid, 2-methyl-, 2-tetradecyloctadecyl ester (EC 946-978-0) was evaluated during a GLP-compliant study performed in accordance with the OECD Testing Guideline 301F (Manometric Respirometry).

The test was performed in closed vessels containing a known concentration of test item in inoculated medium incubated at constant temperature for 28 days. The percent of biodegradation of the test item was calculated based on the Theoretical Oxygen Demand (ThOD) of 3029 mg O2/g test item calculated for the test substance. Oxygen consumption was evaluated through the study.

Sodium acetate was used as reference substance.

The mean biodegradation value of the test item at the end of the test period, on Day 28, was 74% of the ThOD.

Validation criteria were met. A toxicity control indicated that the test substance had no inhibitory effect on the activity of activated sludge microorganisms at the tested concentration of 9.9 mg/L.

Reaction mass of 2-Propenoic acid, 2-methyl-, 2-dodecylhexadecyl ester and 2-Propenoic acid, 2-methyl-, 2-tetradecyloctadecyl ester (EC 946-978-0) was found to be readily biodegradable under the test conditions within 28 days, but failed to meet the 10-day window.

Key value for chemical safety assessment

Biodegradation in water:

readily biodegradable but failing 10-day window

Type of water:

freshwater