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Environmental fate & pathways

Biodegradation in water: screening tests

Administrative data

biodegradation in water: ready biodegradability
Type of information:
experimental study
Adequacy of study:
key study
Study period:
Jun - Jul 1997
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: According to OECD guideline under GLP
Cross-referenceopen allclose all
Reason / purpose for cross-reference:
reference to same study
Reason / purpose for cross-reference:
reference to other study

Data source

Reference Type:
study report
Report date:

Materials and methods

Test guideline
according to guideline
OECD Guideline 301 B (Ready Biodegradability: CO2 Evolution Test)
Principles of method if other than guideline:
not relevant
GLP compliance:

Test material

Constituent 1
Chemical structure
Reference substance name:
17-Hydroxy-1 alpha,2 alpha-methylene-4,6-pregnadiene-3,20-dione
EC Number:
Cas Number:
Molecular formula:
C22 H28 O3
17-Hydroxy-1 alpha,2 alpha-methylene-4,6-pregnadiene-3,20-dione
Details on test material:
- Name of test material (as cited in study report): 1,2 Methylen-4,6-Dien
- Analytical purity: 86%
- Lot/batch No.: 608/2

Study design

Oxygen conditions:
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:

Results and discussion

% Degradation
% degradation (CO2 evolution)
Sampling time:
28 d
Details on results:
The test compound ZK 12126 was practically not degraded on day 30 (~28 days of incubation).

Any other information on results incl. tables

Table 1: Biological degradation (cumulative) in percent (corrected for blank C02-production) of 1,2 Methylen-4,6 -Dien

 Test    Nominal    Day of sampling  
 compound    concentration   3 4 7 9 11 14 18 23 28 30
 of carbon  
 ZK 12126    10 mg/I   1 0 0 1 0 0 2 1 2 2
 Sodium acetate    10 mg/I   14 27 58 67 74 82 88 92 93 96
 ZK 12126 +    10 mg/I +   6 13 29 34 37 41 43 45 45 46
 sodium acetate (toxicity control)    10 mg/I     

Applicant's summary and conclusion

Validity criteria fulfilled:
Interpretation of results:
under test conditions no biodegradation observed
In accordance with the OECD guideline, the test compound 1,2 Methylen-4,6-dien is not readily
biodegradable under the conditions of the test and it was not toxic to the microbes of activated
Executive summary:

The purpose of this study was to determine the ready biodegradability of 1,2 Methylen-4,6-dien, an intermediate in the synthesis of cyproterone acetate. The study was conducted in agreement with the following test guideline: OECD guideline for testing of chemicals, ready biodegradability: C02-evolution test, no. 301 B, adopted Jul. 92, OECD Paris, 93.

The test substance was incubated in an aqueous solution including nutrients with micraorganisms fram a municipal sewage treatment plant for 28 days (start of treatment = day 1). The nutrient solutions were made up of phosphates, ammonium sulphate, magnesium sulphate, iran chloride, ammonium chloride and calcium chloride. The test substance was incubated in a concentration of 10 mg carbon/L in triplicate. Additionally, a reference substance (sodium acetate) was tested in a single set according to the same pracedure, in order to verify the viability and activity of the degrading micraorganisms. One further set was incubated with sodium acetate as 10 mg carbon/L (reference substance) plus test substance as 10 mg carbon/L representing a toxicity control. Furthermore, a blank control was tested in triplicate without any test or reference substance. The biological degradation of the test and reference substances was evaluated by measurement of the carbon dioxide (C02) produced during the test period.

The test compound was practically not degraded on day 30 (28 days of incubation). The reference compound sodium acetate was degraded to 96% on day 30. The time required for 60% biodegradation of the reference compound was less than 10 days. In the toxicity control, the reference compound (sodium acetate) plus the test compound was degraded up to 46% on day 30, thus reflecting the degradation of the substances incubated separately.