3-methoxyoestra-1,3,5(10)-trien-17-one

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Oct -Nov 1994

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

Sampies for the concentration analysis were taken at the time points 0 (measurement vessel) and 48 hours (all test vessels) after start of exposure

Vehicle:

no

Details on test solutions:

Preparation of the stock solution and the test concentration
- 111 mg of Estron-Methylether were suspended in 1000 mL tap water and constantly stirred for 24 hours
- the suspension was filtered through a glassfibre filter
- this solution was used as the highest test concentration
- aliquots of the solution were further diluted 1 :2, 1 :4, 1:8 and 1 :16 with tap water in order to prepare the different test concentrations

Test organisms (species):

Daphnia magna

Details on test organisms:

- Specification: Daphnia magna Straus, Cladocera, Phyllopoda
- Source: Schering AG, Institute of Experimental Toxicology, Berlin, Germany
- Age: 0- 24 hours
- Holding: Parent animals were kept in glass vessels in water of the same quality and temperature as under experimental conditions
- Water: Normal tap water was used as dilution water, not polluted with harmful concentrations of chlorine, heavy metals or other substances, based on quarterly measurements and in accordance with the "Trinkwasserverordnung".

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test temperature:

20.1 - 20.9°C

pH:

7.7 - 8.4

Dissolved oxygen:

7.4 - 9.1 mg/L

Nominal and measured concentrations:

measured concentrations [mg/L]: 0.054, 0.030, 0.013
Due to the limitation of the analytical method no analysis could be performed for the dilutions 1:8 and 1 :16. Thus they were extrapolated:
nominal concentrations [mg/L]: 0.007, 0.003

Details on test conditions:

20 Daphnia were used for each test solution and 20 for the dilution water control, randomly distributed in blocks of five. Labelied 100 mL test vessels were used and filled with 45 mL of the test solution or tap water (control group) and 5 mL of the dilution water with the introduction of the Daphnia. The test was performed with 4 replicates of each test solution and the dilution water control with 5 Daphnia in each vessel. One additional test vessel (measurement vessel) for the test concentration and the control solution, respectively, was used without Daphnia for the measurements of pH, temperature and oxygen content.
The Daphnia were exposed to the test solutions and the dilution water for aperiod of 48 hours under static conditions.
The light/dark rhythm was adjusted to 16 hours/8 hours.

Reference substance (positive control):

no

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

0.04 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mortality

Details on results:

Immobilized Daphnia were observed in the test dilution 1:2 (~ 0.03 mg/L) at 48 hours and in the saturated solution (~ 0.05 mg/L) at 24 hours and 48 hours. The highest dilution without effects was 1:4 (~ 0.01 mg/L).

Validity criteria fulfilled:

yes

Conclusions:

The EC50/48 hours of Estron-Methylether (ZK5512) was determined with 0.04 mg/L. The NOEC was 0.01 mg/L, the LOEC was 0.03 mg/L.

Executive summary:

The study was conducted in agreement with the guideline of the OECD, no. 202, "Daphnia spec., acute immobilization test", adopted: 04 Apr. 84, and the Annex to EEC Directive 92169/EEC, Part. C2: Acute toxicity for Daphnia, Off. J. of the EC, L383, 1992.

20 Daphnia were used tor each test solution of Estron-Methylether and 20 for the dilution water control, randomly distributed in blocks of five. The Daphnia were exposed for aperiod of 48 hours under static conditions. Immobilization was recorded at 24 hours and 48 hours. The test was performed with 4 replicates of each test solution and the dilution water control with 5 Daphnia in each vessel. One additional test vessel (measurement vessel) for the test concentration and the control solution, respectively, was used without Daphnia for the measurements of pH, temperature and oxygen content.

For the preparation of the test solutions a suspension with a nominal concentration of 100 mg/L was prepared and stirred for 24 hours. This suspension was filtered through a glassfibre filter and served as the highest concentration (saturated solution). It was further diluted.

The analytical results gave concentrations of 0.054 mg/L (saturated solution), 0.03 mg/L (1:2 dilution) and 0.013 mg/L (1:4 dilution).The further concentrations were below the limit of determinatio and extrapolated.

The test temperature was in the range of 20.1 to 20.9 °C, the pH range between 7.7 - 8.4 and the oxygen concentration between 7.4 and 9.1 mg/L. The light/dark rhythm was adjusted to 16 hours/8 hours.

The 48h-EC50 of Estron-Methylether to Daphnia magna was calculated to be 0.04 mg/L on the basis of measured concentrations. The highest concentration with no effects was 0.01 mg/L.

Description of key information

The study was conducted in agreement with the guideline of the OECD, no. 202, "Daphnia spec., acute immobilization test", adopted: 04 Apr. 84, and the Annex to EEC Directive 92169/EEC, Part. C2: Acute toxicity for Daphnia, Off. J. of the EC, L383, 1992.

20 Daphnia were used tor each test solution of Estron-Methylether and 20 for the dilution water control, randomly distributed in blocks of five. The Daphnia were exposed for aperiod of 48 hours under static conditions. Immobilization was recorded at 24 hours and 48 hours.

For the preparation of the test solutions a suspension with a nominal concentration of 100 mg/L was prepared and stirred for 24 hours. This suspension was filtered through a glassfibre filter and served as the highest concentration (saturated solution).

The analytical results gave concentrations of 0.054 mg/L (saturated solution), 0.03 mg/L (1:2 dilution) and 0.013 mg/L (1:4 dilution).The two further concentrations were below the limit of determination and extrapolated.

The 48h-EC50 of Estron-Methylether to Daphnia magna was calculated to be 0.04 mg/L on the basis of measured concentrations. The highest concentration with no effects was 0.01 mg/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

EC50

Effect concentration:

0.04 mg/L