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

Short-term toxicity to aquatic invertebrates

Administrative data

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

other: experimental data on similar substance

Adequacy of study:

key study

Study period:

2017

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

other: Study well documented, meets generally accepted scientific principles, acceptable for assessment.

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2017

Report date:

2017

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

yes (incl. QA statement)

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:

A sample of each test concentration was taken for chemical analysis at 0 and 48 hours in order to determine the stability of the test item under test conditions. All samples were stored frozen prior to analysis. Only the 1.0, 10 and 100 mg/L test concentrations were analyzed.

Test solutions

Details on test solutions:

Test concentration verification: Samples were taken from the control and each test group from the bulk test preparation at 0 hours, and from the pooled replicates at 48 hours for quantitative analysis. All samples were stored frozen prior to analysis. Duplicate samples were taken at 0 and 48 hours, and stored frozen for further analysis, if necessary.
Only the samples for the 50% and 100% v/v saturated solution test concentrations were analyzed.
The method of analysis, recovery and test preparation analyses are described in Annex attached to the report.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

Daphnia Magna, Strauss (Cladocera, Crustacea)
- Source: in house laboratory cultures
Adult daphnids were maintained in 150 mL glass beakers containing Elendt M7 medium (see Annex 1) in a temperature controlled room maintaining the water temperature at 18 to 22 °C. The lighting cycle was controlled to give a 16 hours light and 8 hours darkness cycle with 20 minute dawn and dusk transition periods. Each culture was fed daily with a mixture of algal suspension (Desmodesmus subspicatus) and Tetramin® flake food suspension. Culture conditions ensured that reproduction was by parthenogenesis. Gravid adults were isolated the day before initiation of the test, such that the young daphnids produced overnight were less than 24 hours old. These young were removed from the cultures and used for testing. The diet and diluent water are considered not to contain any contaminant that would affect the integrity or outcome of the study.

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test conditions

Test temperature:

21-22°C

pH:

0 h: 7.7-7.8
48 h: 7.8 8

Dissolved oxygen:

0 h: 8.8 mg O2/L
48 h: 8.6 - 8.7mg O2/L

Salinity:

Detailed results in the annex

Nominal and measured concentrations:

0, 0.1, 1, 10 and 100 and 1000 mg/l of active ingredient (dye)

Details on test conditions:

A nominal amount of test item (1100 mg) was dispersed in 11 liters of test water with the aid of propeller stirring at approximately 1500 rpm for 24 hours. After 24 hours, the stirring was stopped and any undissolved test item was removed by filtration through a 0.2 μm Sartorius Sartopore filter (first approximate 2 liters discarded in order to pre-condition the filter) to give a 100% v/v saturated solution. A series of dilutions was made from this saturated solution to give further test concentrations of 6.25, 12.5, 25 and 50% v/v saturated solution.
Each prepared concentration was inverted several times to ensure adequate mixing and homogeneity.
The concentration and stability of the test item in the test preparations was verified by chemical analysis at 0 and 48 hours.

Reference substance (positive control):

yes

Remarks:

K2Cr2O7

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 98 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

mobility

Effect concentrations 2

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 98 mg/L

Nominal / measured:

nominal

Conc. based on:

act. ingr.

Basis for effect:

mobility

Results with reference substance (positive control):

A positive control (Envigo Study Number XT01HS) used potassium dichromate as the reference item at concentrations of 0.32, 0.56, 1.0, 1.8 and 3.2 mg/L.
EC50 (48h) = 1.2 mg/l

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

EC50,48h > 98 mg/l

Executive summary:

The substance was tested for acute toxicity on Daphnia (Immobilisation) following OECD 202.
The test concentraions were 0.1, 1, 10 and 100 mg/l of dye for a total exposure of 48h. Vehicle and positive controls were also performed fulfilling validity criteria for the test. The tested sample under the experimental conditions showed an EC50,48h > 98 mg/l.