[No public or meaningful name is available]

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:

2015

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)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Specific details on test material used for the study:

SOURCE OF TEST MATERIAL
- Source and lot/batch No.of test material: MH-12/2014 (China)
- Expiration date of the lot/batch: 13 November 2019

STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Storage condition of test material: Frozen in the dark

Analytical monitoring:

not specified

Details on sampling:

- Concentrations:
In the range-finding test Daphnia magna were exposed to a series of nominal test concentrations of 0.10, 1.0, 10 and 100 mg/L.
Definitive Test: Based on the results of the range-finding test a "Limit test" was conducted at a concentration of 100 mg/L to confirm that at the maximum concentration recommended in the OECD/EC Test Guidelines, no immobilization or adverse reactions to exposure were observed.

Vehicle:

yes

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
Range-finding Test:
The test concentration to be used in the definitive test was determined by a preliminary range-finding test. In the range-finding test Daphnia magna were exposed to a series of nominal test concentrations of 0.10, 1.0, 10 and 100 mg/L. A nominal amount of test item (50 mg) was dissolved in test water and the volume adjusted to 500 mL to give the 100 mg/L test concentration from which a series of dilutions were made to give further test concentrations of 0.10, 1.0 and 10 mg/L. Each prepared concentration was inverted several times to ensure adequate mixing and homogeneity. In the range-finding test, 10 daphnids were placed in each test and control vessel and maintained in a temperature controlled room at approximately 20 to 21 °C with a photoperiod of 16 hours light and 8 hours darkness for a period of 48 hours with 20 minute dawn and dusk transition periods. Each 250 mL test and control vessel contained 200 mL of test media and was covered to reduce evaporation. After 24 and 48 hours the number of immobilized daphnids was recorded. The control was maintained under identical conditions but not exposed to the test item. A sample of each test concentration was taken for chemical analysis at 0 and 48 hours in order to determine the stability of the test item under test conditions. All samples were stored frozen prior to analysis.

Definitive Test:
Experimental Preparation
A nominal amount of test item (100 mg) was dissolved in test water and the volume adjusted to 1 liter to give the 100 mg/L test concentration. The prepared concentration was inverted several times to ensure adequate mixing and homogeneity.

Exposure Conditions:
As in the range-finding test, 250 mL glass jars containing approximately 200 mL of test preparation were used. At the start of the test, 5 daphnids were placed in each test and control vessel at random, in the test preparations. Four replicate test and control vessels were prepared. The test vessels were then covered to reduce evaporation and maintained in a temperature controlled room at approximately 21 °C with a photoperiod of 16 hours light (577 to 604 lux) and 8 hours darkness with 20 minute dawn and dusk transition periods. The daphnids were not individually identified, received no food during exposure and the test vessels were not aerated. The control group was maintained under identical conditions but not exposed to the test item. The test preparations were not renewed during the exposure period.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Source: The test was carried out using 1st instar Daphnia magna derived from in-house laboratory cultures. Adult daphnia were maintained in 150 mL glass beakers containing Elendt M7 medium in a temperature controlled room at approximately 20 °C. The lighting cycle was controlled to give a 16 hours light and 8 hours darkness cycle with 20 minute dawn and dusk transition periods. Each culture was fed daily with a mixture of algal suspension (Desmodesmus subspicatus) and Tetramin® flake food suspension. Culture conditions ensured that reproduction was by parthenogenesis. Gravid adults were isolated the day before initiation of the test, such that the young daphnids produced overnight were less than 24 hours old. These young ones were removed from the cultures and used for testing. The diet and diluent water are considered not to contain any contaminant that would affect the integrity or outcome of the study. A positive control (Harlan Study Number 41500252) used potassium dichromate as the reference item. Details of the positive control are given in Appendix 2. The positive control was conducted between 23 February 2015 and 25 February 2015.

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Test temperature:

20 °C

pH:

8 and 8.1

Dissolved oxygen:

8.0 - 9.5 mg O2/L

Nominal and measured concentrations:

Range finding test: 0.10, 1.0, 10 and 100 mg/L.
Definitive test: 100 mg/L

Reference substance (positive control):

yes

Remarks:

A positive control (Harlan Study Number 41500252) used potassium dichromate as the reference item at concentrations of 0.32, 0.56, 1.0, 1.8 and 3.2 mg/L.

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Results with reference substance (positive control):

- Mortality: None
- EC50/LC50: 0.75 mg/L (48 h)

No immobilization was observed at the test concentrations of 0.10, 1.0, 10 and 100 mg/L. Based on this information, a single test concentration of 100 mg/L with four replicates was selected for the definitive test. This experimental design conforms to the "Limit test" to confirm that at the maximum test concentration given in the OECD/EC Test Guidelines no immobilization or adverse reactions to exposure were observed. Chemical analysis of the test preparations at 0 and 48 hours showed equivalence to nominal concentrations obtained at 0 and 48 hours, indicating that the test item was stable under test conditions.

Validity criteria fulfilled:

yes

Conclusions:

Exposure of Daphnia magna to FAT 40069/D gave EC50 value of greater than 100 mg/L. The No Observed Effect Concentration was excess of 100 mg/L.

Executive summary:

A GLP-compliant study was performed to assess the acute toxicity of the test item to Daphnia magna acoording to the OECD Guideline 202 and EU Method C.2. Following a preliminary range-finding test, twenty daphnids (4 replicates of 5 animals each) were exposed to an aqueous solution of the test item at a concentration of 100 mg/L for 48 hours at a temperature of approximately 21 °C under static test conditions. Immobilization and any adverse reactions to exposure were recorded after 24 and 48 hours. Analysis of the test preparations at 0 and 48 hours showed measured test concentrations to be near nominal and so the results are based on nominal test concentrations only. No immobilisation was observed throughout the test duration. Hence, exposure of Daphnia magna to the test item gave EC₅₀ value of greater than 100 mg/L. The No Observed Effect Concentration was 100 mg/L.

Description of key information

Exposure of Daphnia magna to FAT 40069 gave an EC50 value of greater than 100 mg/L. The No Observed Effect Concentration (NOEC) was 100 mg/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L

Additional information

A GLP-compliant study was performed to assess the acute toxicity of the test item to Daphnia magna according to the OECD Guideline 202 and EU Method C.2. Following a preliminary range-finding test, twenty daphnids (4 replicates of 5 animals each) were exposed to an aqueous solution of the test item at a concentration of 100 mg/L for 48 hours at a temperature of approximately 21 °C under static test conditions. Immobilization and any adverse reactions to exposure were recorded after 24 and 48 hours. Analysis of the test preparations at 0 and 48 hours showed measured test concentrations to be near nominal and so the results are based on nominal test concentrations only. No immobilisation was observed throughout the test duration. Hence, exposure of Daphnia magna to the test item gave EC₅₀ value of greater than 100 mg/L. The No Observed Effect Concentration was 100 mg/L.