2-[[4-[(2-cyanoethyl)ethylamino]phenyl]azo]-5-nitrobenzonitrile

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

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study without detailed documentation

Qualifier:

equivalent or similar to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

GLP compliance:

not specified

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Common name: rainbow trout.
- Source: Parkwood Trout Farm, Kent, U.K.
- Length at study initiation: 4.0 ± 0.2 cm
- Weight at study initiation: 0.95 ± 0.08 g

ACCLIMATION
- Acclimation conditions: daily media renewal.
- Biomass loading rate: 0.48 g bw/litre
- Health during acclimation: 0 % of mortality during the 7 days before the test start.
- Medication: none.

Test type:

not specified

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Test temperature:

14 ± 1 °C

Nominal and measured concentrations:

1.0 mg/l, nominal.
1.0 mg/l was the highest tested concentration that could be prepared due to the limited solubility of the test item in water and auxiliary solvent and having due regard to the amount of the auxiliary solvent permitted in the test under the OECD guideline. The use of alternative solvents and surfactants did not result in the preparation of a higher test concentration.

Details on test conditions:

TEST SYSTEM
- Test vessel: 20 litres.
- Aeration: yes
- No. of organisms per vessel: 10 fish
- No. of vessels per concentration: 2 replicates.
- No. of vessels per control: 1 replicate.

TEST MEDIUM / WATER PARAMETERS
- Source of dilution water: dechlorinated tap water (sodium thiosulfate).
- Hardness: approx. 50 mg/l as CaCO3.

RANGE FINDING STUDY
- No. of organisms per vessel: 3 fish
- No. of vessels per concentration: 1 replicates
- No. of vessels per control: 1 replicates
- Concentrations: 0.01, 0.1 and 1 mg/l.
- Results: no death occurred at none of the tested concentrations.

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 1 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

No death accurred in none of the control and test item vessels.

Conclusions:

LC50 (96h) > 1.0 mg/l (nominal)

Executive summary:

The acute lethal toxicity of the test substance to rainbow trout was investigated over a period of 96 hours. Based on the results obtained n the preliminary test, the main experiment was conducted at the limit concentration of 1.0 mg/l. No chemical analysis of the test substance was conducted. 1.0 mg/l was the highest tested concentration that could be prepared due to the limited solubility of the test item in water and auxiliary solvent and having due regard to the amount of the auxiliary solvent permitted in the test under the OECD guideline. The use of alternative solvents and surfactants did not result in the preparation of a higher test cocnentration.

At the nominal concentration of 1 .0 mg/l none of fish died after 96 hours of exposure. No mortality was also observed in the blank control.

Conclusion

LC50 (96h) > 1.0 mg/l (nominal)

Description of key information

No acute toxicity (i.e. ErC50) was recorded up to the higher concentration reached in the test.

Additional information

The acute lethal toxicity of the test substance was investigated over a period of 96 hours on rainbow trout. No chemical analysis of the test substance was conducted; 1.0 mg/l was the highest tested concentration that could be prepared due to the limited solubility of the test item in water and auxiliary solvent and having due regard to the amount of the auxiliary solvent permitted in the test under the OECD guideline. The use of alternative solvents and surfactants did not result in the preparation of a higher test cocnentration. At the nominal concentration of 1 .0 mg/l none of fish died after 96 hours of exposure. No mortality was also observed in the blank control. No acute toxicity (i.e. ErC50) was recorded up to the higher concentration reached in the test.