1-Ethoxy-2,3-difluor-4-[4-(trans-4-propylcyclohexyl)-1-cyclohexen-1-yl]-benzene

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:

August 12, 2010 - December 17, 2010

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Version / remarks:

2004

Deviations:

no

Qualifier:

according to guideline

Guideline:

other: The Guidelines for the Testing of Chemicals (HJ/T153-2004)

Version / remarks:

2004

Deviations:

no

GLP compliance:

no

Remarks:

The study was conducted in compliance with CNAS-CL01 (identical to ISO/IEC 17025:2005)

Analytical monitoring:

yes

Details on sampling:

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

Vehicle:

yes

Details on test solutions:

A semi-static test procedure with a daily test medium renewal was chosen to keep the dissolved oxygen concentration in the test solution higher than 60 % of the air saturation value. Prior to each test medium preparation on day 0, 1, 2 and 3, the test medium with the loading rate of 100 mg/L was prepared by weighing 300 mg of the test substance into 3 L of test water. No auxilary solvent or dispersant was used.

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 disperions of the test substance were let stand for 1 hour then filtered through a 0.45 µm of membrane filter. The undiluted filtrates were used as test medium.

Test organisms (species):

Danio rerio (previous name: Brachydanio rerio)

Details on test organisms:

TEST ORGANISM
- Common name: Zebrafish
- Strain: Dania rerio
- Source: Amazonas Commercial Aquarium, Shanghai
- Length at study initiation: 2.4 ± 0.3 cm (Mean +- SD)
- Weight at study initiation: 0.16 ± 0.05 g (Mean +- SD)
- Method of breeding: standard
- Feeding during test: commercial fish diet during acclimatization

ACCLIMATION
- Acclimation period: 12 days
- Acclimation conditions (same as test or not): same
- Health during acclimation (any mortality observed): no

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Remarks on exposure duration:

test solution renewal after 24h

Post exposure observation period:

no

Hardness:

200 mg/L

Test temperature:

23 ± 1°C

pH:

6.81 - 7.45

Dissolved oxygen:

> 80 %

Salinity:

no data

Conductivity:

641.8 µS/cm

Nominal and measured concentrations:

Nominal concentration: 100 mg/L
Mean measured concentration: <0.055 mg/L

Details on test conditions:

TEST SYSTEM
- Type: open
- Aeration: no
- Renewal rate of test solution (frequency/flow rate): every 24 h
- No. of organisms per vessel: 10
- No. of vessels per concentration (replicates): 2
- No. of vessels per control (replicates): 2


TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: dechlorinated drinking water
- Total organic carbon: 10.5 mg/L
- Culture medium different from test medium: no
- Intervals of water quality measurement: daily

OTHER TEST CONDITIONS
- Adjustment of pH: no
- Photoperiod: light dark cycle was 12h:12h


TEST CONCENTRATIONS
- Range finding study: Yes
- Test concentrations: 0.1, 1, 10 and 100 mg/L

Reference substance (positive control):

no

Remarks:

Periodically, the 24h-LC50 of potassium dichromate was determined in order to verify the sensivity of the Brachydanio rerio.

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:

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

Results with reference substance (positive control):

- Results with reference substance valid? Yes (the 24h-LC50 of potassium dichromate should range 200 mg/L to 400 mg/L)
- LC50: 218 mg/L

Validity criteria fulfilled:

yes

Conclusions:

The 96h LC50 was above the water solubility limit and larger than 100 mg/L (nominal) in fish.

Executive summary:

The acute toxicity effect of the test substance to zebrafish (Brachydanio rerio) was determined in a 96-hour semi-static test with a daily test medium renewal conducted according to OECD 203. A limit test was performed in accordance with the result of the preliminary test 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.

The analytically measured test substance concentrations in the analyzed test medium samples were <0.055 mg/L both at the beginning and the end of the test, respectively. The biological results are related to the treatments of 100 mg/L and the mean measured test substance concentration of <0.055 mg/L. In the controls and the treatments at the loading rate of 100 mg/L (mean measured concentration <0.055 mg/L) no fish death was determined during the limit test period of 96 hours.

No aquatic toxicity was observed in this test system up to a nominal concentration of 100 mg/L test material. The 96h LC50 was above the water solubility limit and larger than 100 mg/L (nominal).

Description of key information

The 96h LC50 was above the water solubility limit and larger than 100 mg/L (nominal) in fish.

Additional information

Key study (OECD 203, 2010)

The acute toxicity effect of the test substance to zebrafish (Brachydanio rerio) was determined in a 96-hour semi-static test with a daily test medium renewal conducted according to OECD 203. A limit test was performed in accordance with the result of the preliminary test 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.

The analytically measured test substance concentrations in the analyzed test medium samples were <0.055 mg/L both at the beginning and the end of the test, respectively. The biological results are related to the treatments of 100 mg/L and the mean measured test substance concentration of <0.055 mg/L. In the controls and the treatments at the loading rate of 100 mg/L (mean measured concentration <0.055 mg/L) no fish death was determined during the limit test period of 96 hours.

No aquatic toxicity was observed in this test system up to a nominal concentration of 100 mg/L test material. The 96h LC50 was above the water solubility limit and larger than 100 mg/L (nominal).

 

Supporting study (OECD 203, 2009)

The acute toxicity of the test material was studied in a pretest for a bioaccumulation study (OECD 305) using solvents to increase exposure. The GLP test was performed according to the METI Guideline: Concentration Test on Chemical Substances in Fish. For this assay a pre-test on acute toxicity in fish according to OECD 203 was performed with Danio rerio. To achieve the exposure concentrations of 100 mg/L, solvent Tween 80 (100 mg/L) was used. All concentrations tested were at or above the solubility limit of the pure test substance. Negative control and vehicle control did not show signs of toxicity. The positive control showed mortality in the expected concentration range. At a test material concentration of 100 mg/L (nominal), adjusted with solubiliser, no mortality was observed after 24, 48, 72 and 96 hours, respectively. The test material does not possess acute toxic potential to fish up to the limit of solubility in water. The 96 hours LC50 exceeds the water solubility limit of the pure substance. The LC50 of the test material exceeds 100 mg/L (nominal) and is clearly above the limit of water solubility.