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

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

experimental study

Adequacy of study:

key study

Study period:

Jan 8, 2008 - Mar 11, 2008

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: The Guidelines for the Testing of Chemicals No. 203

Version / remarks:

China Environmental Science Press, 2004

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

The actual concentration of the test substance in the test medium was analytically determined at the beginning and the end of the test.

Vehicle:

no

Details on test solutions:

Dechlorinated drinking water (Shanghai Shinan Drinking Water Ltd.) is used in the test. The test substance was mixed into the test water as homogeneously as possible by stirring for 4 hours at room temperature in the dark to dissolve a maximum concentration of the test substance in the dispersion. The supersaturated stock dispersions of the test substance were filtered through the 0.45µm of membrane filter. The undiluted filtrates were used as test medium.

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

The test organism, Brachydanio rerio which was obtained from were held in our laboratory for 12 days without any medication. Prior to the test start, they were acclimated for one week under conditions of water quality and illumination similar to those used in the test. During holding and acclimatization until one day before the start of the test the fish were fed with a . During holding and acclimatization no fish died in the test fish batch and all fish were healthy.
TEST ORGANISM
- Common name: Zebrafish
- Strain: not available
- Source: Amazonas Commercial Aquarium, Shanghai
- Length at study initiation (mean and SD): 2.0 ± 0.2 cm
- Weight at study initiation (mean and SD): 0.12 ± 0.03 g

ACCLIMATION
- Acclimation period: 12 days
- Acclimation conditions: same as test conditions
- Type and amount of food during acclimation: commercial fish diet (SANYUAN Artificial Tropical Fish Food, from Beijing Sanyou Beautification Feed Tech. Co., Ltd.)
- Health during acclimation: no mortality observed

FEEDING DURING TEST
no feeding during test

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Hardness:

about 250 mg CaCO3

Test temperature:

23 +/- 1 °C

pH:

7.49 to 7.62

Dissolved oxygen:

80 % or higher

Nominal and measured concentrations:

loading rate: 100 mg/L
mean measured concentration: <0.06 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: glass tank
- Material, size, headspace, fill volume: glass, 3L
- Aeration: no details available
- Renewal rate of test solution: every day
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2
- No. of vessels per positive control (replicates): 2

TEST MEDIUM / WATER PARAMETERS
- Source of dilution water: Dechlorinated drinking water (Shanghai Shinan Drinking Water Ltd.), no details available

OTHER TEST CONDITIONS
- Adjustment of pH:
- Photoperiod: light-dark cycle was 12h: 12h

EFFECT PARAMETERS MEASURED
Mortality, DOC (measured by YSI-58 Dissolved Oxygen Meter, YSI Incorporated), pH (measured by pHS-25 Meter, Shanghai Precision Scientific Instrument Co., Ltd.) and temperature (measured by YU1L Thermometer, Shanghai Gaoxin Instrument Co., Ltd.) were measured once daily. The concentration was analytically determined at the beginning and the end of the test.

TEST CONCENTRATIONS
- Range finding study
- Test concentrations: 0.1, 1, 10, 100 mg/L
- Results used to determine the conditions for the definitive study: yes, no mortality occured.

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 60 µg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Duration:

96 h

Dose descriptor:

NOEC

Effect conc.:

60 µg/L

Nominal / measured:

meas. (geom. mean)

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

A limit test was performed in accordance with the result of the preliminary test to demonstrate that the test substance at the loading rate of 100 mg/L has no acute toxicity effect on Brachydanio rerio.

In the controls and the treatments at the loading rate of 100 mg/L (mean measured concentration <0.06 mg/L) no fish death was determined during the limit test period of 96 hours. Therefore, the 96h-NOEC and the 96h-LC0 of the test substance to zebra fish were determined to be the loading rate of 100 mg/L (mean measured concentration <0.06 mg/L). The 96h-LOEC, the 96h-LC50 and 96h-LC100 were clearly higher than the loading rate of 100 mg/L (mean measured concentration <0.06 mg/L).

The pH values in the treatments and the controls ranged from 7.49 to 7.62, and water temperature was maintained at 23 °C. During the period of the test, the dissolved oxygen concentration was always 80% or higher, which fulfilled the criteria for a valid test.

Results with reference substance (positive control):

The sensitivity of the Brachydanio rerio and conformity with the procedure were supported by the result of the reference substance, potassium dichromate. The 24h-LC50 of the potassium dichromate was calculated as 348 mg/L which fulfilled the criteria for a valid test that the 24h-LC50 of the potassium dichromate should range 200 mg/L to 400 mg/L.

Validity criteria fulfilled:

yes

Conclusions:

Based on these results the test substance has no acute toxicity effect on zebra fish under the present conditions of the test up to a loading rate of 100 mg/L (measured concentration: <0.06 mg/L).

Executive summary:

The acute toxicity effect of the test substance to zebra fish (Brachydanio rerio) was determined in a 96-hour semi-static test with a daily test medium renewal according to OECD 203. A limit test was performed in accordance with the result of the preliminary test to demonstrate that the test substance at a loading rate of 100 mg/L has no acute toxicity effect on the test organisms. Thus, only the treatments at a loading rate of 100 mg/L and the controls were tested. Due to the low water solubility of the test substance and shortage of appropriate auxiliary solvents or dispersants, a supersaturated dispersion of the test substance with a loading rate of 100 mg/L was homogenized by continuously stirred over 4 hours prior to each test medium preparation. Then the dispersion was filtered with the 0.45 µm membrane filter. Only the undiluted filtrate with the maximum concentration of dissolved test substance was used as the test medium. The analytically measured test substance concentrations in the analyzed test medium samples were <0.06 mg/L at both the beginning and the end of the test respectively. The biological results are related to the treatments of 100 mg/L and to the mean measured test substance concentration of <0.06 mg/L (calculated as the average of the test concentration). In the controls and the treatments at the loading rate of 100 mg/L (mean measured concentration <0.06 mg/L) no fish death was determined during the limit test period of 96 hours. Therefore, the 96h-NOEC and the 96h-LC0 of the test substance to zebra fish were determined to be the loading rate of 100 mg/L (mean measured concentration <0.06 mg/L). The 96h-LOEC, the 96h-LC50 and 96h-LC100 were clearly higher than the loading rate of 100 mg/L (mean measured concentration <0.06 mg/L). In conclusion, the test substance had no acute toxic effects on zebra fish under the present conditions of the test. Based on these results the hazardous level of the test substance is slight.

Description of key information

The test substance has no acute toxicity effect on zebra fish under the present conditions of the test up to a loading rate of 100 mg/L (measured concentration: <0.06 mg/L, reference 6.1.1 -1).

Additional information

The acute toxicity effect of the test substance to zebra fish (Brachydanio rerio) was determined in a 96-hour semi-static test with a daily test medium renewal according to OECD 203. A limit test was performed in accordance with the result of the preliminary test to demonstrate that the test substance at a loading rate of 100 mg/L has no acute toxicity effect on the test organisms. Thus, only the treatments at a loading rate of 100 mg/L and the controls were tested. Due to the low water solubility of the test substance and shortage of appropriate auxiliary solvents or dispersants, a supersaturated dispersion of the test substance with a loading rate of 100 mg/L was homogenized by continuously stirred over 4 hours prior to each test medium preparation. Then the dispersion was filtered with the 0.45 µm membrane filter. Only the undiluted filtrate with the maximum concentration of dissolved test substance was used as the test medium. The analytically measured test substance concentrations in the analyzed test medium samples were <0.06 mg/L at both the beginning and the end of the test respectively. The biological results are related to the treatments of 100 mg/L and to the mean measured test substance concentration of <0.06 mg/L (calculated as the average of the test concentration). In the controls and the treatments at the loading rate of 100 mg/L (mean measured concentration <0.06 mg/L) no fish death was determined during the limit test period of 96 hours. Therefore, the 96h-NOEC and the 96h-LC0 of the test substance to zebra fish were determined to be the loading rate of 100 mg/L (mean measured concentration <0.06 mg/L). The 96h-LOEC, the 96h-LC50 and 96h-LC100 were clearly higher than the loading rate of 100 mg/L (mean measured concentration <0.06 mg/L). In conclusion, the test substance had no acute toxic effects on zebra fish under the present conditions of the test. Based on these results the hazardous level of the test substance is slight (reference 6.1.1 -1).