[2R-[2α(E),3β]]-2-[2-(3,4-dihydro-6-methoxy-1(2H)-naphthylidene)ethyl]-2-ethyl-3-hydroxycyclopentan-1-one

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:

Mar - Apr 1993

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

other: According to OECD guideline under GLP

Cross-reference

Cross-reference 1

Reason / purpose for cross-reference:

reference to same study

Cross-reference 2

Reason / purpose for cross-reference:

reference to other study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1994

Report date:

1994

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 D (Ready Biodegradability: Closed Bottle Test)

Deviations:

no

Principles of method if other than guideline:

Not relevant

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

[2R-[2α(E),3β]]-2-[2-(3,4-dihydro-6-methoxy-1(2H)-naphthylidene)ethyl]-2-ethyl-3-hydroxycyclopentan-1-one

EC Number:

257-409-4

EC Name:

[2R-[2α(E),3β]]-2-[2-(3,4-dihydro-6-methoxy-1(2H)-naphthylidene)ethyl]-2-ethyl-3-hydroxycyclopentan-1-one

Cas Number:

51773-49-0

Molecular formula:

C20H26O3

IUPAC Name:

17 beta-Hydroxy-3-methoxy-18-methyl-8,14-seco-1,3,5(10),9(11)-estratetraen-14-one

Test material form:

solid: particulate/powder

Remarks:

migrated information: powder

Details on test material:

- Name of test material (as cited in study report): 13-Ethylsecol
- Analytical purity: 97.9%
- Lot/batch No.: 571030532

Study design

Oxygen conditions:

anaerobic

Inoculum or test system:

activated sludge, domestic (adaptation not specified)

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

2 mg/L

Based on:

ThOD/L

Results and discussion

% Degradation

Parameter:

% degradation (O2 consumption)

Value:

2

Sampling time:

28 d

Details on results:

The test substance attained 2 % biodegradation after 28 days.

Any other information on results incl. tables

The test substance was not found to be inhibitory to activated sewage sludge bacteria under the conditions of this test.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

under test conditions no biodegradation observed

Conclusions:

The test substance may not be termed as readily biodegradable.

Executive summary:

In the context of the evaluation of its potential hazard to the aquatic environment 13 -Ethylsecol (ZK 46072) was studied for ready biodegradability in the closed bottle test. The study was conducted in accordance with OECD Guideline for Testing of Chemicals No. 301 D.

The test substance was dissolved in inorganic nutrient medium (concentration: 2 mg/L) and inoculated with activated sewage sludge bacteria, was incubated in duplicate in sealed bottles for 28 days at 20 ± 1°C. On days 0, 5, 15, and 28 duplicate bottles were taken and the concentration of dissolved oxygen was measured using an oxygen probe. Percent biodegradation values were calculated by comparing the oxygen depletion with the theoretical oxygen demand. The biodegradation was also studied in bottles containing sodium benzoate alone as reference compound (3 mg/L) as well as ZK 46072 (2 mg/L) plus sodium benzoate (3 mg/L) for investigation of inhibitory effects of the test substance, all under the same conditions. The test substance showed almost no degradation. There was no indication of inhibitory effects caused by the test compound. The reference compound showed more than 70% degradation after 5 days.