6-{4-[(1E)-3-methoxy-3-oxoprop-1-en-1-yl]phenoxy}hexyl methacrylate

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:

Sept. 2016 - March 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

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

Version / remarks:

July 1992

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Test material form:

solid: crystalline

Details on test material:

- State of aggregation: Non-aggregated
- Particle size distribution: D50 = 12.2 µm
- Geometric standard deviation (GSD): 0.2
- Shape of particles: not assessed
- Surface area of particles: not determined
- Crystal structure: Crystalline, no further details known
- Coating: None
- Moisture content: 0.03%
- Residual solvent: Non detected
- Activation: Not applicable
- Stabilisation: With Phenothiazine (< 1000 ppm)
- Other:

Specific details on test material used for the study:

Designation in Test Facility: 16082904G
Date of Receipt: 29. Aug. 2016
Condition at Receipt: Room temperature in proper conditions
Name: ROC-601
Batch no.: S23PSG0816
Appearance: White crystalline powder
Composition: 99.5% purity, see analytical certificate
CAS No.: 439661-46-8
Molecular formula: C20H26O5
Molecular weight: 346.42 g/mol
Purity: 99.5% by LC-UV
Homogeneity: Uniform crystalline powder
Stability: H2O: unknown; EtOH: unknown; acetone: unknown; CH3CN: unknown; DMSO: unknown
Solubility: H2O: unknown; EtOH: unknown; acetone: unknown; CH3CN: unknown; DMSO: unknown
Production date: 29. Jun. 2016
Expiry date: July 2017
Storage: Room Temperature (20 ±5 °C), keep away from light
SMILES Code: C(=O)(C(=C)C)OCCCCCCOc1ccc(C=CC(=O)OC)cc1
Storage: The test item was stored in a tightly closed vessel at room temperature (17.0 – 20.5 °C) under dry conditions in the dark.

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, non-adapted

Details on inoculum:

Activated sludge from a biologic sewage treatment plant was used. The sludge was taken from the activation basin of the ESN (Stadtentsorgung Neustadt) sewage treatment plant, Im Altenschemel, NW-Lachen-Speyerdorf. The chosen plant is treating mostly domestic sewage (date of collection: 28. Oct. 2016, batch no: 20161028).
The sludge was filtrated, washed with tap water (2x), then washed with and re-suspended in test medium. It was then aerated until use. The dry matter was determined as 3700 mg suspended solids/L.

Duration of test (contact time):

28 d

Initial test substance concentration

Initial test substance concentration 1

Initial conc.:

28.9 mg/L

Based on:

test mat.

Initial test substance concentration 2

Initial conc.:

20 mg/L

Based on:

TOC

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

CO2 evolution

Reference substance

Reference substance:

aniline

Results and discussion

Test performance:

All validity parameters and values were as follows:
- IC content of test item solution in medium: Criterion: ≤ 5% of TC, Found: 10.78 %, Result: *see below
- CO2 emitted by the controls: Criterion: < 70 mg/L, Found: 15.0 mg/L%, Result: valid
- Difference within replicates: Criterion: ≤ 20%, Found: 1.4 %%, Result: valid
- Degradation of positive control > 60%: Criterion: ≤ 14 days, Found: 9 days%, Result: valid
- Degradation in the toxicity flask on day 14: Criterion: > 25%, Found: 54.2 %%, Result: valid

* The IC content of test item in medium was more than 5 % of TC as demanded in the guideline. This is due to the fact that the test item is very poorly soluble in water. Therefore, the validity criterion is not applicable for the test item.

% Degradation

% Degradation 1

Parameter:

% degradation (CO2 evolution)

Value:

76

Sampling time:

28 d

Remarks on result:

other: ultimately biodegradable

% Degradation 2

Parameter:

% degradation (CO2 evolution)

Value:

48

Sampling time:

19 d

Remarks on result:

other: end of 10-day window (day 9 - 19)

Remarks:

not readily biodegradable

Details on results:

Results for the Test Item ROC-601
The test item ROC-601 is considered as “not ready biodegradable”.
The degree of biodegradation reached 76 % after 28 days.
The 10-day-window began on day 9, at its end, 48 % degradation were reached, missing the pass level of 60 % given in the OECD guideline.
Degradation surpassed 60% within 28 days. Therefore, the test item is considered as “ultimately biodegradable within 28 days”.
Abiotic degradation was not observed.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

readily biodegradable, but failing 10-day window

Conclusions:

The test item ROC-601 is not readily biodegradable following OECD 301B/EU C.4-C. As degradation surpassed 60% in the course of the test, ROC-601 is considered as ultimately biodegradable within 28 days.

Executive summary:

ROC-601 was investigated for biodegradability “Determination of the aerobic ready biodegradability of ROC-601 in the CO₂ Evolution Test following OECD 301B resp. EU C.4-C”.

The test item ROC-601 was tested using a concentration of nominally 20 mg organic carbon/L (corresponding to 28.9 mg ROC-601/L) in test medium following OECD 301B and EU-Method C.4-C.

Aniline was chosen as positive control. Activated sludge was used as inoculum (concentration in the test 25.0 mg dry matter/L). The test was left running for 28 days.

All validity criteria were met. Degradation of the positive control was 70 % after 9 days.

The following data were determined for the test item ROC-601:

- 10-day-window: day 9 – 19
- degradation at the end of 10-day-window 48 %
- degradation at the end of the test: 76 %
Pass level following guideline: 60% at the end of 10-day-window for pure substances respective 60 % at the end of the test for mixtures.

Therefore, when applying the 10-day-window, the test item ROC-601 is not readily biodegradable following OECD 301B/EU C.4-C. As degradation surpassed 60% in the course of the test, ROC-601 is considered as ultimately biodegradable within 28 days.