tert-butyl peracetate

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:

2017-03 till 2017-06

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

Qualifier:

according to guideline

Guideline:

EPA OPPTS 850.1010 (Aquatic Invertebrate Acute Toxicity Test, Freshwater Daphnids)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

- Sampling method: samples from each concentration at start and end of water renewal period

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: mechanical dispersion (intensive shaking): For preparation of test solutions (at each renewal period) a stock solution of 25 mg/L (nominal concentration) was first prepared by dissolving an amount of 0.025 g test item in 1000 mL ISO medium using approx. 1.5 - 2 hours of intensive shaking to obtain clear solution. After the formulation procedure the test animals were immediately introduced into the test solution.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Strain: Daphnia magna (Straus)
- Source: Laboratory of Hydrobiology (Central Agricultural Office, Directorate of Plant-, and Soil Protection), 2100 Gödöllő, Kotlán S. u. 3. Hungary
- Age at test start: less than 24 hours
- Sex: female
- Feeding during test: no

ACCLIMATION
- Acclimation period: No. Test animals were bred under similar conditions as that used during the exposure period

Test type:

semi-static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Hardness:

249 mg/L (as CaCO3)

Test temperature:

19.4 – 20.3°C

pH:

7.86 – 8.48 (not adjusted)

Dissolved oxygen:

7.71 – 8.83 mg/L

Nominal and measured concentrations:

Nominal concentrations: 0.2, 0.5, 1.0, 2.3, 5.0, 11, 24 and 53 mg/L
Measured concentrations (geometric mean): : 0.12, 0.24, 0.55, 1.26, 2.67, 7.06, 15.10 and 32.58 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: Glass beakers
- Fill volume: 100 mL
- Aeration: no
- Renewal rate of test solution: each 24 h
- No. of organisms per vessel: 5
- No. of vessels per concentration: 4 replicates
- No. of vessels per control: 4 replicates

TEST MEDIUM / WATER PARAMETERS
- Preparation of dilution water: ISO medium (according to OECD 202)
- Dissolved Oxygen Concentration: 8.50 - 8.57 mg/L
- pH: 7.86 - 8.03
- Culture medium different from test medium: no

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 hours light/ 8 hours darkness
- Light intensity: 687 - 643 Lux

EFFECT PARAMETERS MEASURED BEFORE AND AFTER WATER RENEWAL:
- pH
- Dissolved Oxygen Concentration
- Temperature

RANGE-FINDING STUDY
- Test concentrations: 1, 10 and 100 mg/L
- Results used to determine the conditions for the definitive study: yes

Reference substance (positive control):

yes

Remarks:

Potassium dichromate

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

4.31 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

48 h

Dose descriptor:

EC10

Effect conc.:

2.81 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality

Key result

Duration:

48 h

Dose descriptor:

NOEC

Effect conc.:

2.67 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality

Duration:

48 h

Dose descriptor:

LOEC

Effect conc.:

7.06 mg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality

Details on results:

- Behavioural abnormalities: no
- Observations on body length and weight: no
- Mortality of control: no
- Other adverse effects control: no
- Abnormal responses: no
- Any observations that might cause a difference between measured and nominal values: no
- Effect concentrations exceeding solubility of substance in test medium: no

Results with reference substance (positive control):

- Results with reference substance valid: yes
24-h EC50: 1.41 mg/L, (95 % confidence limits: 1.19 – 1.68 mg/L)

Validity criteria fulfilled:

yes

Conclusions:

The EC50 (48 h) of the test item was calculated to be 4.31 mg/L with 95 % confidence limits of 3.42 and 5.45 mg/L.
The highest concentration causing no immobility (no observed effect concentration, NOEC) after 48 hours amounted to 2.67 mg/L, whereas 7.06 mg/L was the lowest tested concentration (LOEC, 48 h) at which significant immobility was observed as compared to the control.

Executive summary:

The acute toxicity of the test item to Daphnia magna (water flea) was tested under semi-static conditions for 48 hours in accordance with OECD guideline no. 202 and EU method C.2. The following concentrations were tested: 0.2, 0.5, 1.0, 2.3, 5.0, 11, 24 and 53 mg/L. The measured concentrations deviated more than 20 % from the nominal during the experiment therefore the geometric mean of the concentrations measured at the start and end of the water renewal periods were calculated to determine exposure concentrations. The corresponding calculated geometric mean test item concentrations were: 0.12, 0.24, 0.55, 1.26, 2.67, 7.06, 15.10 and 32.58 mg/L. The EC50 (48 h) was calculated to be 4.31 mg/L with 95 % confidence limits of 3.42 and 5.45 mg/L. The highest concentration causing no immobility (no observed effect concentration, NOEC) after 48 hours amounted to 2.67 mg/L, whereas 7.06 mg/L was the lowest tested concentration (LOEC, 48 h) at which significant immobility was observed as compared to the control. The EC100 was 1.53 mg/L, which was observed after 48 hours. Sublethal effects were not observed in the test concentrations where no immobility was observed.

Description of key information

The acute toxicity to invertebrates was assessed according to OECD guideline 202 and EU-method C.2. In this 48-hour acute toxicity test with daphnia, the EC50 value was 4.31 mg/L (measured concentration, geometric mean). The no-observed-effect concentration (NOEC) was 2.67 mg/L (nominal concentration). 

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Dose descriptor:

EC50

Effect concentration:

4.31 mg/L

Additional information

The acute toxicity of the test item to Daphnia magna (water flea) was tested under semi-static conditions for 48 hours in accordance with OECD guideline no. 202 and EU method C.2. The following concentrations were tested: 0.2, 0.5, 1.0, 2.3, 5.0, 11, 24 and 53 mg/L. The measured concentrations deviated more than 20 % from the nominal during the experiment therefore the geometric mean of the concentrations measured at the start and end of the water renewal periods were calculated to determine exposure concentrations. The corresponding calculated geometric mean test item concentrations were: 0.12, 0.24, 0.55, 1.26, 2.67, 7.06, 15.10 and 32.58 mg/L. The EC50 (48 h) was calculated to be 4.31 mg/L with 95% confidence limits of 3.42 and 5.45 mg/L. The highest concentration causing no immobility (no observed effect concentration, NOEC) after 48 hours amounted to 2.67 mg/L, whereas 7.06 mg/L was the lowest tested concentration (LOEC, 48 h) at which significant immobility was observed as compared to the control. The EC100 was 1.53 mg/L, which was observed after 48 hours. Sublethal effects were not observed in the test concentrations where no immobility was observed.