5H-Dicyclopropa[6,7:15,16]cyclopenta[a]phenanthrene-3,5,17-triol, octadecahydro-17-(3-hydroxypropyl)-10,13-dimethyl-, (3S,5R,6R,7R,8R,9S,10R,13S,14S,15S,16S,17S)-

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:

Nov - Dec 2001

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2005

Report date:

2005

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 301 F (Ready Biodegradability: Manometric Respirometry Test)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

17 alpha-(3-Hydroxypropyl)-6 beta,7 beta;15 beta,16 beta-dimethylene-5 beta-androstane-3 beta,5,17 beta-triol

EC Number:

617-350-0

Cas Number:

82543-18-8

Molecular formula:

C24 H38 O4

IUPAC Name:

17 alpha-(3-Hydroxypropyl)-6 beta,7 beta;15 beta,16 beta-dimethylene-5 beta-androstane-3 beta,5,17 beta-triol

Test material form:

solid

Study design

Oxygen conditions:

aerobic

Inoculum or test system:

activated sludge, domestic, non-adapted

Details on inoculum:

- Source of inoculum/activated sludge (e.g. location, sampling depth, contamination history, procedure): sewage treatment plant Kläranlage Berlin Ruhleben
- Storage conditions: room temperature

Duration of test (contact time):

28 d

Initial test substance concentration

Initial conc.:

200 mg/L

Based on:

ThOD/L

Parameter followed for biodegradation estimation

Parameter followed for biodegradation estimation:

O2 consumption

Details on study design:

TEST CONDITIONS
- Composition of medium: according to guideline
- Test temperature: 22 °C
- pH: The pH was 7.7 to 7.8 in the blank and the substance vessels, 9.0 to 9.4 in the reference and toxicity control vessels
- Continuous darkness: yes

TEST SYSTEM
- Culturing apparatus: Oxitop
- Number of culture flasks/concentration: 3

SAMPLING
- Sampling frequency: after 2, 6, 10, 14, 18, 22, 26, 29 days

CONTROL AND BLANK SYSTEM
- Inoculum blank: yes, 3 vessels
- Toxicity control: yes, 1 vessel

Reference substance

Reference substance:

benzoic acid, sodium salt

Results and discussion

% Degradation

Key result

Parameter:

% degradation (O2 consumption)

Value:

9

Sampling time:

29 d

Details on results:

Degradation toxicity control: 47% on day 29 (28 days of exposure)

BOD5 / COD results

Results with reference substance:

Degradation reference substance: 70% on day 29 (28 days of exposure)

Any other information on results incl. tables

Biological degradation (cumulative) in percent (corrected for blank O2 consumption) of ZK 92836 (selected time points)

		Days of sampling
Test compound	Concentration expressed in theoretical O2 demand	2	6	10	14	18	22	26	29
ZK 92836	200 mg/L	1	2	3	6	9	9	7	5
Reference (sodium acetate)	200 mg/L	27	70	65	65	67	67	65	64
Toxicity control (ZK 92836 + sodium acetate)	100 mg/L + 100 mg/L	27	41	46	49	51	51	48	47

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Interpretation of results:

not readily biodegradable

Conclusions:

The test compound ZK 92836 is not readily biodegradable under the conditions of the test.

Executive summary:

The purpose ofthis study was to determine the ready biodegradability of Dimethylenpropanol (ZK 92836), which is an intermediate of the synthesis of Drospirenone. The study was conducted in agreement with the OECD test guideline no. 301F.

The test substance ZK 92836 was incubated in an aqueous solution including nutrients with microorganisms from a municipal sewage treatment plant for 28 days (start of treatment = day 1). The test substance ZK 92836 was incubated at a concentration of 200 mg theoretical oxygen demand (ThOD) per liter. Additionally, a reference substance (sodium acetate) was tested in a single set according to the same procedure, in order to verify the viability and activity of the degrading microorganisms. One further set was incubated with sodium acetate at 100 mg ThOD/L (reference substance) plus ZK 92836 at 100 mg ThOD/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 O2 consumption during the test period.

The test compound ZK 92836 was degraded to less than 10 % until day 29 (28 days of incubation). The reference compound sodium acetate was degraded to 70% on day 6 and did not increase until day 29 (28 days of incubation). In the toxicity control, the reference compound (sodium acetate) plus the test compound ZK 92836, was degraded to 47% on day 29 (28 days ofincubation), which reflected the degradation in the individual sets.

In accordance with the OECD, the test compound ZK 92836 is not readily biodegradable under the conditions of the test and it was not toxic to the microbes of activated sludge .