Acetic acid, 2,2-difluoro-2-[[2,2,4,5-tetrafluoro-5-(trifluoromethoxy)-1,3-dioxolan-4-yl]oxy]-, ammonium salt (1:1)

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:

2009-04-27 until 2009-10-10

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Remarks:

Guideline-conform study under GLP without deviations.

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)

Remarks:

Swiss Federal Office of Public Health, 2008-11-12

Specific details on test material used for the study:

Details on properties of test surrogate or analogue material (migrated information):
not applicable

Analytical monitoring:

yes

Details on sampling:

- Concentrations: 100 mg/l of dry salt of test item cC604 (i.e. 625 mg/l of test item cC604, which contains 16% active ingredient)
- Sampling method: Duplicate samples were taken from each treatment before the start of the test and at the end of the test after 48 hours.
- Sample storage conditions before analysis: All samples were stored deep-frozen (at about -20 °C) immediately after sampling.

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
The test medium was prepared by mixing 156.3 mg of the test item cC6O4 into 250 mL of test water using ultrasonic treatment for 15 minutes and intense stirring for 15 minutes at room temperature. The test medium was prepared just before introduction of the daphnids (i.e., start of the test).

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: water fleas
- Strain: Daphnia magna Straus.
- Source: A clone of this species (defined by the supplier as clone 5) was originally supplied by the University of Sheffield / UK in 1992. Since that time, the clone has been bred at Harlan Laboratories in reconstituted water of the quality identical to the water quality used in the tests and under temperature and light conditions identical to those of the tests.
- Age at study initiation (mean and range, SD): 6-24 hours
- Weight at study initiation (mean and range, SD): not applicable
- Length at study initiation (length definition, mean, range and SD): not applicable
- Valve height at study initiation, for shell deposition study (mean and range, SD): not applicable
- Peripheral shell growth removed prior to test initiation: not applicable
- Method of breeding: see "source"
- Feeding during test: The daphnids were not fed during the test.


ACCLIMATION
not applicable, daphnids are being bred in the testing laboratory
- Acclimation conditions (same as test or not): not applicable, daphnids are being bred in the testing laboratory


QUARANTINE (wild caught)
not applicable, daphnids are being bred in the testing laboratory

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Post exposure observation period:

not reported

Hardness:

2.5 mmol as CaCO3

Test temperature:

20 °C

pH:

between 8.0 and 8.1

Dissolved oxygen:

8.3 mg/L

Salinity:

No data, however detailed description of the mineral composition of the test medium is given in the study report.

Nominal and measured concentrations:

Nominal concentration: 625 mg test item cC6O4/L, corresponding to 100 mg dry salt cC6O4/L (test item cC6O4 contains 84% water).
Measured concentration: 105 to 106% of the nominal value.

Details on test conditions:

TEST SYSTEM
- Test vessel:
- Type (delete if not applicable): open; test vessels were covered with glass plates to reduce the loss of water by evaporation and to avoid the entry of dust into the solutions.
- Material, size, headspace, fill volume: 100-mL glass beakers filled with 50 mL of test medium
- Aeration: The test water was aerated prior to the start of the study until oxygen saturation was reached. During the test period, the test water was not aerated.
- Type of flow-through (e.g. peristaltic or proportional diluter): not applicable
- Renewal rate of test solution (frequency/flow rate): no renewal
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
- No. of vessels per vehicle control (replicates): not applicable
- Biomass loading rate: no data


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Reconstituted test water according to ISO 6341 was used in the study.
- Total organic carbon: not applicable
- Particulate matter: not applicable
- Metals: not applicable
- Pesticides: not applicable
- Chlorine: not applicable
- Alkalinity: 0.8 mmol/l
- Ca/mg ratio: 4:1
- Conductivity: No data, however detailed description of the mineral composition of the test medium is given in the study report.
- Culture medium different from test medium: no
- Intervals of water quality measurement: samples taken at the start and at the end of the test after 48 hours.


OTHER TEST CONDITIONS
- Adjustment of pH: no data
- Photoperiod: 16-hour light to 8-hour dark cycle with a 30-minute transition period
- Light intensity: between 520 and 680 Lux.


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : The daphnids were observed for immobility after 24 and 48 hours of exposure (daphnids not being able to swim within 15 seconds after gentle agitation of the test beaker are considered to be immobilized).


TEST CONCENTRATIONS
- Spacing factor for test concentrations: limit test
- Justification for using less concentrations than requested by guideline: A limit test was performed in accordance with the test guidelines to demonstrate that the test item cC6O4 has no toxic effect on the test organisms up to the nominal concentration of 625 mg test item cC6O4/L, corresponding to 100 mg dry salt cC6O4/L (test item cC6O4 contains 84% water). Thus, a single nominal concentration of the test item cC6O4 of 625 mg/L was tested.
- Range finding study: not applicable

Reference substance (positive control):

yes

Remarks:

For evaluation of the quality of the daphnia clone and the experimental conditions, potassium dichromate is tested as a positive control twice a year.

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 625 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC0

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC0

Effect conc.:

>= 625 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:

act. ingr.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

>= 625 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Behavioural abnormalities: none reported
- Observations on body length and weight: none reported
- Other biological observations: none reported
- Mortality of control: no mortalities reproted
- Other adverse effects control: none reported
- Abnormal responses: none reported
- Any observations (e.g. precipitation) that might cause a difference between measured and nominal values: none reported
- Effect concentrations exceeding solubility of substance in test medium: none reported

Results with reference substance (positive control):

- Results with reference substance valid? yes
The result of the latest positive control test in February 2009 (48-hour EC50: 0.71 mg/L) indicated that the sensitivity of the test organisms was within the internal historical range (48-hour EC50 from 1996 to 2009: 0.53-1.1 mg/L).

Reported statistics and error estimates:

no statistics applied

Validity criteria fulfilled:

yes

Remarks:

no immobilized test otganisms in the controls; positive controls valid

Conclusions:

The 48-hour NOEC and EC0 of the test item cC6O4 ammonium salt to Daphnia magna were determined to be at least 100 mg dry salt cC6O4/L.

Executive summary:

The acute toxicity of the test item cC6O4 ammonium salt to Daphnia magna was determined in a 48-hour static test according to the EU Commission Directive 92/69/EEC, Part C.2, Commission Regulation (EC) No 440/2008, Part C.2 and the OECD Guideline for Testing of Chemicals, No. 202 (2004). A limit test was performed in accordance with the guidelines to demonstrate that the test item cC6O4 ammonium salt has no toxic effect on the test organisms at a nominal concentration of 625 mg test item cC6O4 ammonium salt/L corresponding to 100 mg dry salt cC6O4 ammonium salt/L (test item aqueous solution of cC6O4 ammonium salt contains 84% water). Thus, a single nominal concentration of the test item cC6O4 ammonium salt was tested. In the control and at the test item cC6O4 ammonium salt concentration of 100 mg dry salt cC6O4/L, no immobilized test organisms were observed during the test period of 48 hours. The summary of the biological results (based on nominal test item concentration of cC6O4 ammonium salt expressed as content of dry salt cC6O4 ammonium salt) is as follows:

– 48 -hour EC50: >100

– 48 -hour EC0 and 48 -hour NOEC: ≥100

In conclusion, the test item cC6O4 ammonium salt had no acute toxic effects on Daphnia magna up to the nominal concentration of 100 mg dry salt cC6O4 ammonium salt/L (corresponding to 625 mg test item cC6O4 ammonium salt/L) under the present test conditions.

Description of key information

The acute toxicity of the test item cC6O4 ammonium salt to Daphnia magna was determined in a 48-hour static test according to the EU Commission Directive 92/69/EEC, Part C.2, Commission Regulation (EC) No 440/2008, Part C.2 and the OECD Guideline for Testing of Chemicals, No. 202 (2004).
The study was performed under GLP without deviations.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L

Additional information

The limit test demonstrates that the test item cC6O4 ammonium salt has no toxic effect on the test organisms at a nominal concentration of 625 mg test item cC6O4 ammonium salt/L corresponding to 100 mg dry salt cC6O4 ammonium salt/L (test item = aqueous solution of cC6O4 ammonium salt containing 84% water).

EC50-48 hours > 100 mg/l (based on active ingredient)