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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
Study period:
Mar - Apr 1998
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: According to OECD guideline under GLP

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1998
Report date:
1998

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:
7α-bromo-5,6β-epoxy-15β,16β-methylene-3β-pivaloyloxy-5β-androstan-17-one
EC Number:
617-834-1
Cas Number:
863329-69-5
Molecular formula:
C25H35BrO4
IUPAC Name:
7α-bromo-5,6β-epoxy-15β,16β-methylene-3β-pivaloyloxy-5β-androstan-17-one
Details on test material:
- Name of test material (as cited in study report): Bromepoxid (ZK137314)
- Analytical purity:
- Lot/batch No.:

Study design

Oxygen conditions:
aerobic
Inoculum or test system:
activated sludge, domestic (adaptation not specified)
Duration of test (contact time):
28 d
Initial test substance concentration
Initial conc.:
10 mg/L
Based on:
test mat.

Results and discussion

% Degradation
Parameter:
% degradation (CO2 evolution)
Value:
0
Sampling time:
28 d
Details on results:
Degradation of reference compound: 83%
Degradation of toxicity control: 47%

Any other information on results incl. tables

Biological degradation (cumulative) in percent (corrected for blank C02-production) of ZK 137314

 Test    Nominal    Day of sampling  
 compound    concentration       
    of carbon   4 7 11 16 21 25 30
 ZK 137314    10 mg/L  0 0 0 0 0 0 0
 Sodium acetate    10 mg/L 24 43 59 71 77 80 83
 (reference)                          
 ZK 137314 +    10 mg/L +   13 22 31 38 42 44 47
 sodium acetate    10 mg/L                       
 (toxicity control)                          

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Interpretation of results:
under test conditions no biodegradation observed
Conclusions:
The test compound ZK 137314 was not degraded by day 30 (28 days of incubation).
Executive summary:

The purpose of this study was to determine the ready biodegradability of ZK 137314, an intermediate of the synthesis of drospirenone. The study was conducted in agreement with the following test guideline: OECD guideline for testing of chemicals, Ready biodegradability: CO2-evolution test, no. 301 B.

The test substance ZK 137314 was incubated in a concentration of 10 mg carbon/I in triplicate in an aqueous solution including nutrients with micraorganisms fram a municipal sewage treatment plant for 28 days. The biological degradation of the test and reference substances was evaluated by measurement of the carbon dioxide (CO2) produced during the test period.

The test compound ZK 137314 was not degraded by day 30 (28 days of incubation). The reference compound sodium acetate was degraded to 83% on day 30 (28 days of incubation). In the toxicity control, the reference compound (sodium acetate) plus the test compound ZK 137314 was degraded up to 47% on day 30 (28 days of incubation), thus reflecting the degradation of the substances incubated separately.