2H-Pyran, 2-[4'-[difluoro(3,4,5-trifluorophenoxy)methyl]-3',5'-difluoro[1,1'-biphenyl]-4-yl]-5-ethyltetrahydro-

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:

2007-11-23 to 2007-12-06

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Version / remarks:

31st July 1992

Deviations:

no

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

2004-04-13

Deviations:

no

GLP compliance:

yes

Analytical monitoring:

no

Remarks:

The development of an analytical method with a sufficiently low detection and quantification limit would be very time and cost intensive. Due to the absence of any adverse effects at the saturation concentration, the study was performed without analytic.

Vehicle:

no

Details on test solutions:

The test medium (reconstituted water and test material) was freshly prepared. Therefore, the calibrated flask with test medium was treated in an ultrasonic device for 1 hour. Subsequently, the preparation was stirred with a magnetic stirrer for further 23 hours. The formulation was then passed through a single use syringe filter (pore size 0.2 µm). The filtrate was used for the study.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Water flea
- Strain/clone: Strauss
- Age at study initiation: not older than 24 h
- Source: Merck KGaA, Darmstadt, Institute of Toxicology
- Feeding during test : no

ACCLIMATION
- Acclimation period: no

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Hardness:

about 14 ° dH (about 250 mg/L CaCO3)

Test temperature:

18 - 22°C

pH:

7.9 +/- 0.3

Dissolved oxygen:

95.2 - 98.6 %

Nominal and measured concentrations:

Nominal concentration: 100 mg/L (limit test)
due to the low water solubility and the fact that the study was a limit test, no further analysis was initiated.

Details on test conditions:

TEST SYSTEM
- Test vessel: glass vessels
- Type: open
- Material: glass
- Volume of solution: 10 mL
- Aeration: no
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4
- Biomass loading rate: 5 daphnia/10 mL

TEST MEDIUM / WATER PARAMETERS
- Preparation of dilution water: Reconstituted water according to ELENDT (1990):
Macro nutrients (mg/L):
CaCI2 x 7 H20 293.80
MgSO4 x 7 H20 123.30
NaHCO3 64.80
KCI 5.80
Na2SiO3 x 9H20 10.00
NaNO3 0.27
KH2PO4 0.14
K2HPO4 0.18

Trace elements (mg/L):
B 0.5000
Fe 0.2000
Mn 0.1000
Li, Rb and Sr 0.0500
Mo 0.0250
Br 0.0125
Cu and Zn 0.0063
Co and I 0.0025
Se 0.0010
V 0.0003
Macro nutrients (mg/L): Na2EDTA x 2H20 2.50
Vitamins (µg/L):
Thiamine 75.00
B12 1.00
Biotin 0.75
After preparation, the reconstituded water was aerated for 24 hours.

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: 16 hours light - 8 hours dark
- Light intensity: no details available

EFFECT PARAMETERS MEASURED
mobility of Daphnia: after 24 and 48h
pH, O2 was measured at start and end of experiment, temperature was measured constantly

RANGE-FINDING STUDY
no details available

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Behavioural abnormalities: no
- Mortality of control: no
- Other adverse effects control: no
- Immobilisation of control: no
- Abnormal responses: no
- Any observations that might cause a difference between measured and nominal values: no

Daphnia magna exposed to a nominal concentration of 100 mg/L (limit test) for 48 hours in an open static system were not affected. The test material concentration in the aqueous medium was not quantified at the start and at the end of this study as a very low water solubility was calculated for this test item (ca. 0.059 µg/L). Therefore, the development of an analytical method with a sufficiently low detection and quantification limit would be very time and cost intensive. Due to the absence of any adverse effects at the saturation concentration, the study was performed without analytical concentration verification. For the test material, the following EC50 values for Daphnia magna were determined: 24h-EC50: > 100 mg/L nominal, 48h-EC50: > 100 mg/L nominal.

Results with reference substance (positive control):

no details available

Validity criteria fulfilled:

yes

Conclusions:

Under the given experimental conditions, the test material showed a 24h and 48h EC50 value > 100 mg/L nominal.

Executive summary:

The objective of this study was to determine the acute toxicity of the test item using Daphnia magna according to OECD 202 and EU Method C.2. For this purpose, juvenile Daphnia magna were exposed to an aqueous test material solution over 48 hours under defined conditions. The study comprised of four test vessels per concentration containing five Daphnia magna each, i.e. 20 Daphnia magna per concentration (test medium group) and control group. Daphnia were exposed to a nominal test material concentration of 100 mg/L (limit test) in an open static system.The test material concentration in the aqueous medium was not quantified at the start and at the end of this study as a very low water solubility was calculated for this test item (< 0.085 mg/L). Therefore, the development of an analytical method with a sufficiently low detection and quantification limit would be very time and cost intensive. Due to the absence of any adverse effects at the saturation concentration, the study was performed without analytical concentration verification. Daphnia magna exposed to an aqueous preparation of the nominal concentration of 100 mg/L were not affected. For the test material, the following EC50 values for Daphnia magna were determined: 24h-EC50: > 100 mg/L nominal, 48h-EC50: > 100 mg/L nominal.

Description of key information

The test material showed a 24h and 48h EC50 value > 100 mg/L nominal (reference 6.1.3 -1).

Additional information

The objective of the study was to determine the acute toxicity of the test item using Daphnia magna according to OECD 202 and EU Method C.2. For this purpose, juvenile Daphnia magna were exposed to an aqueous test material solution over 48 hours under defined conditions. The study comprised of four test vessels per concentration containing five Daphnia magna each, i.e. 20 Daphnia magna per concentration (test medium group) and control group. Daphnia were exposed to a nominal test material concentration of 100 mg/L (limit test) in an open static system.The test material concentration in the aqueous medium was not quantified at the start and at the end of this study as a very low water solubility was calculated for this test item (ca. 0.059 µg/L). Therefore, the development of an analytical method with a sufficiently low detection and quantification limit would be very time and cost intensive. Due to the absence of any adverse effects at the saturation concentration, the study was performed without analytical concentration verification. Daphnia magna exposed to an aqueous preparation of the nominal concentration of 100 mg/L were not affected. For the test material, the following EC50 values for Daphnia magna were determined: 24h-EC50: > 100 mg/L nominal, 48h-EC50: > 100 mg/L nominal (reference 6.1.3 -1).