3-methoxyestra-2,5(10)-dien-17-one

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Aug 2002

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:

2002

Report date:

2004

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation 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:

3-methoxyestra-2,5(10)-dien-17-one

EC Number:

241-893-9

EC Name:

3-methoxyestra-2,5(10)-dien-17-one

Cas Number:

17976-32-8

Molecular formula:

C19H26O2

IUPAC Name:

3-methoxyestra-2,5(10)-dien-17-one

Details on test material:

- Name of test material (as cited in study report): Dihydro-Estron-Methylether
- Analytical purity: 99.9%
- Lot/batch No.: 29023001

Sampling and analysis

Analytical monitoring:

yes

Test solutions

Vehicle:

no

Test organisms

Test organisms (species):

Daphnia magna

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Results and discussion

Effect concentrations

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

ca. 1 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Any other information on results incl. tables

Table 1: Cumulative immobilization (%) ofDaphnia magna (n=20) after exposure to ZK 28521

Concentration of ZK 28521	24 hours	48 hours
control (tap water)	0	0
Saturated solution	0	45

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The EC50/48 hours ofZK 28521 to Daphnia magna is expected to be approximately at the level of the maximum solubility < 1.0 mg/L, as
determined by TOC analysis). Since ZK 28521 has a low hydrolytical stability, it is assumed that the toxicity to Daphnia magna is based mainly on
the transformation products. Accordingly, ZK 28521 and its transformation products are very toxic to Daphnia magna.

Executive summary:

The purpose of the study was to determine the acute toxicity (immobilization, EC50/48 hours) of Dihydro-Estron-Methylether (ZK 28521) with Daphnia magna in order to evaluate the aquatic toxicity. ZK 28521 is an intermediate of the synthesis of Gestonorone. The study was conducted as a limit test according to the following guidelines of the OECD, no. 202.

20 juvenile Daphnia magna were used for the test solution and 20 for the tap water control. The Daphnia were exposed for aperiod of 48 ho urs under static conditions. Immobilization was recorded at 24 hours and 48 hours. For the preparation ofthe test solution, a suspension with a nominalloading of 100 mg/L was stirred for 24 hours. This suspension was filtered through a glassfibre filter. The saturated solution obtained by this procedure was used. The organie carbon concentration of the test solution was analyzed with a TOC analyzer at the start of exposure and 48 hours thereafter. The substance concentration was calculated on the basis of the molecular formula. The mean concentration was calculated with < 1mg/L.

The EC50/48 hours of Dihydro-Estron-Methylether to Daphnia magna is expected to be approximately at the level ofthe maximum solubility.