7-anilino-4-hydroxy-3-[[6-methoxy-4-[(6-sulpho-2,4-xylyl)azo]-m-tolyl]azo]naphthalene-2-sulphonic acid, sodium salt, compound with 2,2',2''-nitrilotriethanol

Short-term toxicity to fish

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to fish

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Study period:

May from 02nd to 09th, 2017

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Justification for type of information:

Details for read across approach are included into the IUCLID section 13.

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Version / remarks:

1992

GLP compliance:

yes (incl. QA statement)

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.

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 (species):

Oncorhynchus mykiss (previous name: Salmo gairdneri)

Details on test organisms:

TEST ORGANISM
- Source: Brow Well Fisheries Limited, Hebden, near Skipton, Yorkshire, UK.
- Length at study initiation: mean standard length of 5.6 cm (sd = 0.37).
- Weight at study initiation: mean weight of 1.46 g (sd = 0.33).
- Feeding during the test: discontinued approximately 24 hours prior to the start of the definitive test.

ACCLIMATION
- Acclimation period: fish were acclimatized to test conditions for 7 days.
- Acclimation conditions: fish were maintained in a glass fiber tank with a "single pass" water renewal system. The lighting cycle was controlled to give a 16 hours light and 8 hours darkness cycle with 20 minute dawn and dusk transition periods. The water temperature was controlled at 14 to 15 °C with dissolved oxygen content of greater than or equal to 9.6 mg O2/l.
- Type of food during acclimation: commercial trout pellets.

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Test temperature:

Test vessels: 14 - 15 °C
Control: 14 - 15 °C

pH:

Test vessels: 7.8 - 8.2
Control: 7.8 - 8.2

Dissolved oxygen:

Test vessels: 9.6 - 10.5 mgO2/l
Control: 9.3 - 10.8 mgO2/l

Nominal and measured concentrations:

98 mg/l nominal

Details on test conditions:

TEST SYSTEM
- Test vessel: 25-30 liter glass aquaria containing 20 liters of test media for the control and test concentration.
- Coverage: the test vessels were then covered to reduce evaporation.
- Aeration: test vessels were aerated via narrow bore glass tubes.
- Renewal rate of test solution: daily renewal of the test preparations.
- No. of organisms per vessel: 7
- No. of vessels per concentration: 1 replicate
- No. of vessels per control: 1 replicate

TEST MEDIUM / WATER PARAMETERS
- Preparation of dilution water: laboratory tap water was dechlorinated by passage through an activated carbon filter (Purite Series 500) and partly softened (Elga Nimbus 1248D Duplex Water Softener).
- Total hardness: approximately 140 mg/l as CaCO3.

OTHER TEST CONDITIONS
- Photoperiod: 16 hours light and 8 hours darkness with 20 minute dawn and dusk transition periods for 96 hours.

OBSERVATION
Any mortalities and sub-lethal effects of exposure were recorded at 1, 3, 6, 24, 48, 72 and 96 hours after the start of exposure. The criteria of death were taken to be the absence of both respiratory movement and response to physical stimulation.

PARAMETERS MEASURED
The water temperature, pH and dissolved oxygen concentrations were recorded daily throughout the test. The measurements at 0 hours, and after each test media renewal at 24, 48 and 72 hours, represent those of the freshly prepared test preparations while the measurements taken prior to each test media renewal, and on termination of the test after 96 hours, represent those of the used or 24-Hour old test preparations. The pH and dissolved oxygen concentration were measured using a Hach Flexi handheld meter, whilst the temperature was measured using a Hanna Instruments HI 93510 digital thermometer.

TEST CONCENTRATIONS
In accordance with the recommendations of REACh, the test was conducted according to the threshold approach recommended by ECHA. Using this approach the lowest EC50 value from either the Lemna Growth Inhibition study or Acute Toxicity to Daphnia magna study was set as the threshold loading rate and a “limit test” was conducted at this threshold loading rate. If no mortalities were observed this indicates that fish were not the most sensitive species and that the LC50 is greater than the threshold loading rate. The EC50 value obtained from the Acute Toxicity to Daphnia magna study was the lowest; hence, the test was conducted at a single concentration of 98 mg/l.

VALIDITY OF THE TEST
The results of the test are considered valid if the following criteria are met:
- in the control, not more than one of the fish should die or show signs of stress during the 96 hours.
- the dissolved oxygen concentration at the end of the test should be greater than or equal to 60 % of Air Saturation Values (ASV) in the control and test vessels.

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. The No Observed Effect Concentration (NOEC) was 98 mg/l.
A sub-lethal effect of exposure was observed in the 98 mg/l test concentration: the fish were observed to have a slight staining on the fins and around the mouth, but otherwise were observed to be normal.

APPEARANCE OF TEST MEDIUM
At the start and throughout the test the control was observed to be a clear, colorless solution; however, the 98 mg/l test solution was observed to be a dark, purple solution.

MEASURED CONCENTRATIONS
Chemical analysis of the fresh test preparations at 0 and 72 hours and the aged test preparations at 24 and 96 hours, showed measured test concentrations to range from 98 to 99 % of nominal, and so the results are based on nominal test concentrations only.

Validity criteria fulfilled:

yes

Remarks:

none of the control fish died or showed signs of stress during the test and the oxygen concentration at the end of the test was equal to or greater than 60 % of ASV in the control and test vessels

Conclusions:

LC50 (96h) > 98 mg/l (nominal)

Executive summary:

A study was performed to assess the acute toxicity of the test item to rainbow trout (Oncorhynchus mykiss). The method followed was designed to be compatible with the OECD Guidelines for Testing of Chemicals (1992) No 203, "Fish, Acute Toxicity Test" referenced as Method C.1 of Commission Regulation (EC) No. 440/2008.

The reference EC50 value to set the limit test concentration was obtained from the Acute Toxicity to Daphnia magna study; the test was conducted at a single concentration of 98 mg/l.

Seven fish were exposed to an aqueous solution of the test item, at a single concentration of 98 mg/l for a period of 96 hours at a temperature of 14 to 15 ºC under semi-static test conditions. The number of mortalities and any sub-lethal effects of exposure in each test and control vessel were determined 1, 3 and 6 hours after the start of exposure, and then daily throughout the test until termination after 96 hours.

Chemical analysis of the fresh test preparations at 0 and 72 hours, and the aged test preparations at 24 and 96 hours, showed measured test concentrations to range from 98 to 99 % of nominal, and so the results are based on nominal test concentrations only.

Exposure of rainbow trout to the test item gave LC50 values of greater than 98 mg/l. The No Observed Effect Concentration was 98 mg/.

Conclusion

LC50 (96h) > 98 mg/l (nominal)

Description of key information

Not harmful/toxic for short-term exposure to fish

Additional information

The substance (commercial formulation) was assayed for the short-term toxicity potential to fish, according to the ETAD reccomendations. Unfortunately, only a sheet of test results is currently available; therefore, there are no details about actual test conditions and results. The information has been here mentioned for completeness sake.

The Lethal Concentration for 0 % of population was identified to be 456 mg/l, while the 100 % of mortality was indicated to be caused by 870 mg/l. The CL50 was reported to be 663 mg/l (sheet of results, 1987).

In order to clarify the short-term toxicity to fish potential of Direct Violet 051, the available data on structural analogous Similar Substance 01 have been taken into account. The read across approach can be considered as reliable and adequate for the purpose; details and explanations are detailed in the report attached to the IUCLID section 13.

A study was performed with rainbow trout, according to the OECD Guideline No 203. The reference EC50 value to set the limit test concentration was obtained from the Acute Toxicity to Daphnia magna study; the test was conducted at a single concentration of 98 mg/l. No deaths were recorded overt the 96 hours exposure period. Therefore, the No Observed Effect Concentration (NOEC) was 98 mg/l. A sub-lethal effect of exposure was observed in the 98 mg/l test concentration: the fish were observed to have a slight staining on the fins and around the mouth, but otherwise were observed to be normal.

At the start and throughout the test the control was observed to be a clear, colorless solution; however, the 98 mg/l test solution was observed to be a dark, purple solution.

Chemical analysis of the fresh test preparations at 0 and 72 hours and the aged test preparations at 24 and 96 hours, showed measured test concentrations to range from 98 to 99 % of nominal, and so the results are based on nominal test concentrations only.

REFERENCE

Complete reference are included into the CSR file.