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Environmental fate & pathways

Biodegradation in water: screening tests

Administrative data

Endpoint:
biodegradation in water: ready biodegradability
Type of information:
experimental study
Adequacy of study:
other information
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: well repoted GLP study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2000

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test)
Deviations:
no
GLP compliance:
yes

Test material

Constituent 1
Chemical structure
Reference substance name:
Gestonorone
EC Number:
218-378-2
EC Name:
Gestonorone
Cas Number:
2137-18-0
Molecular formula:
C20H28O3
IUPAC Name:
14-acetyl-14-hydroxy-15-methyltetracyclo[8.7.0.0²,⁷.0¹¹,¹⁵]heptadec-6-en-5-one

Study design

Oxygen conditions:
aerobic
Inoculum or test system:
activated sludge, domestic, non-adapted
Duration of test (contact time):
ca. 28 d

Results and discussion

% Degradation
Value:
70
Sampling time:
28 d

Applicant's summary and conclusion

Interpretation of results:
inherently biodegradable, not fulfilling specific criteria
Executive summary:

The ready biodegradability of gestonorone was studied in a CO2 evolution test according to OECD 305B. The test compound was incubated with a suspension of activated sludge from a municipal sewage treatment plant over a period of 28 days. A reference substance (sodium acetate) was used as positive control and a toxicity control with gestonorone and sodium acetate was used to study the potential toxicity to sewage sludge microorganisms. The test compound was degraded to 70% after 28 days. However, the degradation of 60 % was not reached during the 10 days window as required according to the guideline. Therefore, gestonorone was not ready biodegradable but showed significant degradation and can be expected to be inherently biodegradable in appropriate test designs. The test was performed according to GLP (report X515, study TXST20000174).