Registration Dossier

Ecotoxicological information

Short-term toxicity to aquatic invertebrates

Currently viewing:

Administrative data

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:
07 April 2017 - 07 September 2017
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study
Remarks:
GLP compliant
Reason / purpose:
reference to other study
Qualifier:
according to
Guideline:
OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)
Version / remarks:
2004
Deviations:
no
GLP compliance:
yes (incl. certificate)
Remarks:
Inspection dates: 7 - 11, 14 and 16 September 2015. Date of the certificate: 03 November 2015.
Specific details on test material used for the study:
STABILITY AND STORAGE CONDITIONS OF TEST MATERIAL
- Appearence: clear colourless liquid
- Test item storage: in refrigerator (2-8°C)
Analytical monitoring:
yes
Details on sampling:
- Test concentrations: 10, 18, 32, 56 and 100 mg/L
Vehicle:
no
Details on test solutions:
PREPARATION AND APPLICATION OF TEST SOLUTION (especially for difficult test substances)
- Method: Preparation of test solutions started with the highest concentration of 100 mg/L. Exact volumes of the test item (84 µL per litre) were pipetted just below the surface and then a 10-minute period of low intensity stirring was applied to ensure homogenisation of the test itemin medium. Lower test concentrations were prepared by subsequent dilutions of the highest concentration in test medium. All test solutions were clear and colorless at the end of the preparation procedure.
- Controls: test medium without test item or other additives
- Chemical name of vehicle: no vehicle
- Concentration of vehicle in test medium: no vehicle
- Evidence of undissolved material: the test substance was completely soluble in test medium at concentrations tested.
Test organisms (species):
Daphnia magna
Details on test organisms:
TEST ORGANISM
- Common name: Daphnia magna (Crustacea, Cladocera)
- Strain/clone: At least third generation, obtained by a cyclical parthenogenesis under specified breeding conditions.
- Justification for species other than prescribed by test guideline: This system has been selected as an internationally accepted invertebrate species.
- Source: In-house laboratory culture with a known history.
- Age of daphnids: For the test selection of young daphnids with an age of < 24 hours, from parental daphnids of more than two weeks old.
- Feeding during test: No feeding during the main test
- Food type: Suspension of fresh water algae.

ACCLIMATION
- Acclimation period: 4 weeks maximum
- Acclimation conditions: 18-22°C (same as test)
- Type and amount of food: Suspension of fresh water algae.
- Feeding frequency: Daily.
- Medium: M7
Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
48 h
Hardness:
180 mg/L expressed as CaCO3
Test temperature:
18-22°C
pH:
Start (t= 0h): 7.8
End (t= 48h): 7.9
Dissolved oxygen:
Start (t= 0h): 9.0-9.1
End (t= 48h): 7.5-8.0
Nominal and measured concentrations:
Nominal concentrations: 10, 18, 32, 56 and 100 mg/L
Measured concentrations (t= 0h): 10.7, 11.5, 19.3, 36.7 and 62.6 mg/L
Measured concentrations (t= 48h): 9.09, 10.3, 19.2, 33.6 and 59.9 mg/L
Details on test conditions:
TEST SYSTEM
- Test vessel: glass
- Type: airtight closed
- Material, size, headspace, fill volume: 60 mL, all-glass and completely filled with no headspace
- Feeding: No feeding
- Aeration: No aeration of the test solutions
- No. of organisms per vessel: 5 per vessel containing 60 mL of test solution
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

TEST MEDIUM / WATER PARAMETERS
- Details of composition of culture and test medium are provided in section "Attached background material"
- Culture medium different from test medium: yes

OTHER TEST CONDITIONS
- Adjustment of pH: Not specified
- Photoperiod: 16 hours photoperiod daily
- Light intensity: Not specified

EFFECT PARAMETERS MEASURED: Incidence of immobility at 0, 24 and 48h.

VEHICLE CONTROL PERFORMED: no as no vehicle used

COMBINED/RANGE-FINDING STUDY
- Limit test concentration: 100 mg/L
- Test concentrations: 0.10, 1.0 and 10 mg/L
- Results used to determine the conditions for the definitive study: No immobility was observed at any of the test concentrations during the test period, except for one replicate (rep. C) of the highest test concentration where all daphnids were immobile at the study end.
Reference substance (positive control):
yes
Remarks:
Potassium dichromate (K2Cr2O7)
Key result
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
46 mg/L
Nominal / measured:
meas. (arithm. mean)
Conc. based on:
test mat.
Basis for effect:
mobility
Remarks on result:
other: 95%-CI: 35-61
Details on results:
The 24h-EC50 could not be determined because the observed effects were below 50%. Thus, 24h-EC50 was greater than 61 mg/L.

The 48h-EC50 could not be determined using the maximum likelihood estimation method with the probits of the percentages of immobile larvae as function of the logarithms of the corresponding concentrations. This was because there was no concentration between the highest concentration (A) at which 0% immobility and the lowest concentration (B) at which 100% immobility occurred. Instead, the EC50 was calculated as (AB)½, with A and B being limits of the 95% confidence interval. Thus, 48h-EC50 was 46 mg/L.
Results with reference substance (positive control):
The reference test was carried out to check the sensitivity of the test system as used by Charles River Den Bosch. Daphnia were exposed for a maximum of 48 hours to K2Cr2O7 concentrations of 0.10, 0.18, 0.32, 0.56, 1.0 and 1.8 mg/L and to a control. Twenty daphnids were exposed per concentration. The EC50 at 24 and 48 hours of exposure were determined.

The actual responses in this reference test with K2Cr2O7 are within the ranges of the expected responses at the different concentrations (i.e., the 48h-EC50 was between 0.3 and 1.0 mg/L). Hence, the sensitivity of this batch of D. magna was in agreement with the historical data collected at Charles River Den Bosch.
The 24h-EC50 was 0.64 mg/L with a 95% confidence interval between 0.56 and 0.73 mg/L.
The 48h-EC50 was 0.48 mg/L with a 95% confidence interval between 0.43 and 0.53 mg/L.

Results with reference substance were considered as valid.
Validity criteria fulfilled:
yes
Conclusions:
Under the test conditions, the 48h-EC50 for Daphnia magna exposed to 1,1,1-trifluoroacetone was 46 mg/L based on average exposure concentrations (95% confidence interval between 35 and 61 mg/L). Therefore, 1,1,1-trifluoroacetone is considered as harmful to aquatic life.
Executive summary:

The ability of 1,1,1 -tyrifluoroacetone to generate acute toxic effects on the mobility of Daphnia magna during an exposure period of 48 hours was investigated using an acute immobilisation test according to the OECD guideline No. 202 and under GLP conditions.

A range-finding test allowed to determine that nominal testing concentrations between 10 and 100 mg/L are acceptable for the main test.

In the main test, daphnids were exposed to 9.9, 11, 19, 35 and 61 mg/L (average exposure concentrations based on measured concentrations at the beginning and at the end of the test) for a 48h-exposeure period. The toxic effects of the test substance was determined by measuring the mobility of Daphnia magna.

Under the test conditions, the 48h-EC50 for Daphnia magna exposed to 1,1,1-trifluoroacetone was 46 mg/L based on average exposure concentrations (95% confidence interval between 35 and 61 mg/L).

Description of key information

Harmful to aquatic invertebrate (OECD 202, GLP compliant, Key Rel. 1)

Key value for chemical safety assessment

EC50/LC50 for freshwater invertebrates:
46 mg/L

Additional information

One key study was identified for acute toxicity to aquatic invertebrates in freshwater .

The ability of 1,1,1 -tyrifluoroacetone to generate acute toxic effects on the mobility of Daphnia magna during an exposure period of 48 hours was investigated using an acute immobilisation test according to the OECD guideline No. 202 and under GLP conditions.

A range-finding test allowed to determine that nominal testing concentrations between 10 and 100 mg/L are acceptable for the main test.

In the main test, daphnids were exposed to 9.9, 11, 19, 35 and 61 mg/L (average exposure concentrations based on measured concentrations at the beginning and at the end of the test) for a 48h-exposeure period. The toxic effects of the test substance was determined by measuring the mobility of Daphnia magna.

Under the test conditions, the 48h-EC50 for Daphnia magna exposed to 1,1,1-trifluoroacetone was 46 mg/L based on average exposure concentrations (95% confidence interval between 35 and 61 mg/L).