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Ecotoxicological information

Short-term toxicity to aquatic invertebrates

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Administrative data

Endpoint:
short-term toxicity to aquatic invertebrates
Type of information:
experimental study
Adequacy of study:
key study
Study period:
48 h
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2020
Report Date:
2020

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)
GLP compliance:
yes (incl. certificate)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: particulate/powder

Sampling and analysis

Analytical monitoring:
yes

Test solutions

Details on test solutions:
The test organism was bred and held in Elendt M4 medium which was also used for preparing of test item solutions. Young daphnids aged less than 24 hours at the start of the experiment were exposed to the test item for a period of 48 hours and acute toxic effect displayed as immobilization of test organism recorded at 24 and 48 hours after the start of test. The stock solution was prepared by measuring 150.21 mg of test item into 1 000 ml Elendt M4 growth medium. The suspension was stirred and ultrasonicated till complete dilution. After stirring the stock solution was clear and colourless. The measured concentration of stock solution was 150.00 mg/L.

Test organisms

Test organisms (species):
Daphnia magna
Details on test organisms:
Test species: Daphnia magna Straus
Age: < 24 hours neonates
Origin: National Institute of Environmental Health
Date of arriving: 16 May 2013
Culture conditions: The test species is maintained in Elendt M4 medium with culture conditions at 21±1 °C and a light/dark cycle of 16/8 hours with light intensities of less than 1000 Lux. The cultures are fed with centrifugalized green alga (Pseudokirchneriella subcapitata) cells daily at weekdays.

Study design

Test type:
static
Water media type:
freshwater
Limit test:
yes
Total exposure duration:
48 h

Test conditions

Test temperature:
The test vessels were covered with plastic lids and were kept in thermostat at 21 ± 1 °C with a 16/8 hours light/dark cycle. The temperature of thermostat was recorded daily and registered continuously by Extech datalogger.
The temperature inside the thermostat at the test vessels was measured and
registered continuously by Extech SD200 thermometer and datalogger.
pH:
The pH was measured at the beginning and at the end of the test. At the beginning of the test the pH was measured from the remaining test solutions of the concurrent test vessels at each dilution levels. At the end of the test the pH was measured in each test vessel.
Dissolved oxygen:
Dissolved oxygen was measured at the beginning and at the end of the test. At the beginning of the test dissolved oxygen was measured from the remaining test solutions of the concurrent test vessels at each dilution levels. At the end of the test dissolved oxygen was measured in each test vessel.
Nominal and measured concentrations:
The toxic property of test item was investigated at six concentrations which were prepared by different dilutions of stock solution of test item. Elendt M4 medium was used for dilution of stock solution. In the test the following nominal concentrations were applied: 150.00; 110.00; 90.00; 60.00; 40.00 and 20.00 mg/L.
The concentration of test item was measured at each concentration level at start and at the end of the test by a validated HPLC method. The geometric means of measured concentrations were determined. The following actual concentrations were calculated from the measured values in the test: 148.74; 110.11; 89.60; 59.99; 39.20 and 19.34 mg test item/L.
Details on test conditions:
At each concentration level four replicates were prepared. Each test vessel contained 5 daphnids in 50 ml test solution. The test vessels were covered with plastic lids and were kept in thermostat at 21 ± 1 °C and 16/8 hours light/dark cycle. The controls were kept under the same conditions in Elendt M4 medium.
Reference substance (positive control):
yes

Results and discussion

Effect concentrationsopen allclose all
Duration:
48 h
Dose descriptor:
EC10
Effect conc.:
91.16 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
122.85 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Details on results:
The effective concentrations (ECx) were calculated with Probit analysis using linear max. Likelihood regression. The EC10, EC20 and EC50 were calculated for immobility at both 24 h and 48 h period.
The No Observed Effect Concentration (NOEC) and Lowest Observed Effect Concentration (LOEC) of the test item were determined with Fisher’s exact binominal test with Bonferroni correction by ToxRat® software. The results were not conclusive.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
Acute toxic effect of 15α-hydroxy-androstenedione was investigated in Daphnia sp. Acute Immobilisation test (according to OECD 202 guideline).
The EC50 was 122.85 mg/L at 48 h. In this Daphnia sp., Acute Immobilisation Test for 15α-hydroxy-androstenedione the results indicated that the test item is not hazardous to the aquatic environment. [48 hr EC50 (for Crustacea) > 100 mg/L]