Disodium 4-hydroxy-3-[[2-methoxy-5-methyl-4-[(4-sulphonatophenyl)azo]phenyl]azo]-7-(phenylamino)naphthalene-2-sulphonate

Short-term toxicity to fish

Administrative data

Endpoint:

short-term toxicity to fish

Type of information:

other: exerimental data on similar substance

Adequacy of study:

key study

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: The test was performed following official guideline, some details on test conditions are missing. Study meets generally accepted scientific principles,acceptable for assessment.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Deviations:

no

GLP compliance:

yes

Test material

Test material information

Constituent 1

Reference substance name:

Trisodium 3-[[4-[[6-(anilino)-1-hydroxy-3-sulphonato-2-naphthyl]azo]-5-methoxy-o-tolyl]azo]naphthalene-1,5-disulphonate

EC Number:

228-327-6

EC Name:

Trisodium 3-[[4-[[6-(anilino)-1-hydroxy-3-sulphonato-2-naphthyl]azo]-5-methoxy-o-tolyl]azo]naphthalene-1,5-disulphonate

Cas Number:

6227-20-9

Molecular formula:

C34H27N5O11S3.3Na

IUPAC Name:

trisodium;3-[[4-[(2E)-2-(6-anilino-1-oxo-3-sulfonatonaphthalen-2-ylidene)hydrazinyl]-5-methoxy-2-methylphenyl]diazenyl]naphthalene-1,5-disulfonate

Sampling and analysis

Analytical monitoring:

yes

Details on sampling:

Water samples were taken from the control and 98 mg/L test preparations at 0, 24, 48 and 72 hours from fresh media, and at 24, 48, 72 and 96 hours from old media, for quantitative analysis. The samples were stored frozen prior to analysis.
Duplicate samples at 0 (fresh media), 24 (old media), 72 hours (fresh media) and 96 hours (old media) were taken and stored frozen for further analysis, if necessary.
The concentration and stability of the test item in the test preparations were verified by chemical analysis in fresh test preparations at 0 and 72 hours, and in aged test media at 24 and 96 hours. As all measured concentrations from these samples were within 20% of the nominal concentration and no mortalities or sub-lethal effects of the exposed fish were observed, analysis of the remaining samples was considered not to be necessary. The method of analysis, recovery and test preparation analyses are described in the Annexes.

Test solutions

Vehicle:

yes

Remarks:

water

Details on test solutions:

A nominal amount of test item (1960 mg) was dissolved in a 20 liter volume of test water with the aid of sonication for 30 minutes to give a 98 mg/L stock solution. The stock solution was siphoned through a net to ensure all test item had dissolved.
The test concentration was stirred with a flat bladed mixer for approximately 1 minute to ensure homogeneity of the solution.

Test organisms

Test organisms (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

Supplier: Brow Well Fisheries Limited, Hebden, near Skipton, Yorkshire, UK
Lenght: mean value 5.6 cm
Weight: mean value 1.46 g

The water temperature was controlled at 14 °C to 15 °C with dissolved oxygen content of greater than or equal to 9.6 mg O2/L. These parameters were recorded daily. The stock fish were fed commercial trout pellets, which were discontinued approximately 24 hours prior to the start of the definitive test.

Study design

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Test conditions

Nominal and measured concentrations:

98 mg/L of active indredient

Details on test conditions:

The test vessels were 25-30 liter glass aquaria containing 20 liters of test media for the control and test concentration. At the start of the test, seven fish were placed in each test vessel at random, in the test preparations. The test vessels were then covered to reduce evaporation and maintained at 14 °C to 15 °C in a temperature controlled room with a photoperiod of 16 hours light and 8 hours darkness with 20 minute dawn and dusk transition periods for 96 hours. The test vessels were aerated via narrow bore glass tubes. The fish were not individually identified and received no food during exposure.
The control group was maintained under identical conditions, but not exposed to the test item.

Reference substance (positive control):

no

Results and discussion

Effect concentrations

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 98 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Details on results:

There were no mortalities in 7 fish exposed to a test concentration of 98 mg/L for a period of 96 hours.

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

LC50 96h > 98 mg/l

Executive summary:

The acute toxicity of the test item to the freshwater fish rainbow trout (Oncorhynchus mykiss) has been investigated and based on the nominal concentration gave a 96-Hour LC50 of greater than 98 mg/L. The No Observed Effect Concentration was 98 mg/L.