9beta,11beta-Epoxy-6alpha-fluoro-16alpha-methyl-21-valeryloxy-1,4-pregnadiene-3,20-dione

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:

1992

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study without detailed documentation

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

yes

Remarks:

Draft report

Analytical monitoring:

yes

Details on sampling:

Temperature, pH- and oxygen values were measured at the beginning (0 h) and end of the test (48 h).

Vehicle:

yes

Remarks:

triethylene glycol

Details on test solutions:

Preparation of the stock solution and the test concentration:
- 11, 25 and 50 mg of test item were dissolved each in 10 mL of triethylene glycol; from this solutions 500 µL triethylene glycol were dissolved in 500 mL of tap water to prepare nominal concentrations (1.0, 2.3 and 4.5 g/L)
- For the control group 500 µL triethelene glycol were dissolved in 500 mL tap water
- Therefore, the concentration of triethylene glycol in the test concentration and in the control group was 1.13 g/L (specific gravity: 1.13 g/mL)

Test organisms (species):

Daphnia magna

Details on test organisms:

- Age: parthenogenetic females
- Source: Schering AG, Experimental Toxicology
- Age: 1-24 hours
- Maintenance and Acclimatisation: 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" (Lundt and Schiwy, 1986)

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

The hardness of the dilution water used was 14.2 °dH (253 mg/L CaCO3)

Test temperature:

20.8 °C (after 48 h) concerning the highest test concentration

pH:

8.7 (after 48 h) concerning the highest test concentration

Dissolved oxygen:

8.6 mg/L (after 48 hrs) concerning the highest test concentration

Salinity:

n.a.

Conductivity:

No data

Nominal and measured concentrations:

The analytical results showed a mean concentration of 0.2 mg/L (nominal 1.0 mg/L), 1.0 mg/L (nominal 2.3 mg/L) and 1.4 mg/L (nominal 4.5 mg/L).

Details on test conditions:

EXPOSURE CONDITIONS:
- Test vessels: 100 mL glass beakers covered with watch glasses holding 5 neonates in 50 mL of the test medium
- Experimental design: 3 test concentration plus 1 control; 5 neonates per vessel, 4 replicates per concentration/control
- Method of initiation: neonates were placed in prepared media
- Photoperiod: 12 h light : 12 h dark
- Temperature of incubation unit: 20.0 to 21.3 °C
- Aeration: none
- Test item concentrations: 1.0, 2.3 and 4.5 mg/L
- Method of administration: stock solution
- Medium renewal: none
- Criteria of effects: immobilization and visual abnormalities of the neonates, observed at 24 and 48 hours

Reference substance (positive control):

not specified

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 4.5 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

The test solution with the nominal concentration of 1.0 mg/L of the test substance had no adverse effects on the mobility of Daphnia. At a nominal concentration of 2.3 and 4.5 mg/L a immobilization rate of 15% (after 48 hours) was noted. One and two immobilized Daphnia in the control groups of the test is in the accepted range in the OECD guideline (10%). Therefore, it can be concluded that the EC50 of the test item was higher than 4.5 mg/L nominal, equivalent to 1.4 mg/L measured. The results indicate further that at this maximum concentration tested, there is a slight compound-related effect on the immobilization rate.

Validity criteria fulfilled:

yes

Remarks:

Immobilisation and other abnormalities in the controls did not exceed 10% by the end of the test; dissolved oxygen concentration remained above 3 mg/L throughout the exposure period

Conclusions:

After 48 hours of exposure conditions the EC50 to Daphnia magna was higher than 4.5 mg/L (equivalent to 1.4 mg/L measured). The result is expressed in terms of nominal concentration.

Executive summary:

The study was conducted in agreement with the test guideline of the OECD, no. 202, "Daphnia spec., acute immobilization test"; adopted: 4. April 1984, and the EEC Directive 79/831, Annex V, Part C2: Acute toxicity tor Daphnia (draft) , Brussels 1989.

Twenty test organisms of Daphnia magna were used for each test concentration and for the control group. The Daphnia were exposed to the test concentrations and the dilution water for aperiod of 48 hours under static conditkms. Immobilization was recorded at 24 hours and 48 hours. The test temperature was in the range of 20.0 to 21.3 °C The pH of the test concentration and the control group was 7.7 -8.8, the oxygen concentration was between 8.2 and 9.5 mg/L. The light/dark rhythm was adjusted to 12 hours/12 hours. The nominal test concentrations were 1.0, 2.3 and 4.5 mg/L in three tests. For the concentration analysis samples were taken from each test vessel at 0, 24 and 48 hours. The concentrations were 0.23 mg/L for nominal 1.0 mg/L, 0.96 mg/L for nominal 2.3 mg/L and 1.39 mg/L for nominal 4.5 mg/L. There was a large variation between samples from one concentration. In the highest concentration tested, up to 15% of the test organisms were immobilized, simila!' to the medium concentration. At the lowest concentration, no immobilized Daphnia were observed. Also some immobilized Daphnia were observed in the control groups (up to 10%,). An immobilizaüon of 10% is within the limits recommended by the OECD guideline for organisms in the control group. Accordingly there seems to be a slight exposure related effect at the concentrations of 2.3 and 4.5 mg/L. After 48 hours of exposure conditions the EC50 to Daphnia magna was higher than 4.5 mg/L (equivalent to 1.4 mg/L measured).

This toxicity study is classified as acceptable and satisfies the guideline requirements for the acute Daphnia study.

Description of key information

After 48 hours of exposure conditions the EC50 to Daphnia magna was higher than 4.5 mg/L (equivalent to 1.4 mg/L measured). The result is expressed in terms of nominal concentration.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

EC50

Effect concentration:

> 4.5 mg/L

Additional information

An immobilization of 10% was within the limits recommended by the OECD guideline for organisms in the control group. Accordingly there seems to be a slight exposure related effect at the concentrations of 2.3 and 4.5 mg/L.