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

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:

02 May 2017 to 09 May 2017

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 203 (Fish, Acute Toxicity Test)

Qualifier:

according to guideline

Guideline:

EU Method C.1 (Acute Toxicity for Fish)

Principles of method if other than guideline:

Limit test based on the outcome of the acute dapnia test and lemna test according to the threshold approach as indicated in the REACH guidance

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

From control and 98 mg/L at 0, 24, 48 and 72 hours from fresh media, and at 24, 48, 72 and 96 hours from old media
Samples were frozen before analyses. After thawing the 5 mL samples were diluted with medium (factor 10).

Vehicle:

no

Details on test solutions:

The test water is dechlorinated and softened tap water (analytical details are provided in the report and no contaminants that would affect the integrity and outcome of the study were found)

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
- Common name: Rainbow trout (Oncorhynchus mykiss)
- Source: Brow Well Fisheries Limited, Hebden, near Skipton, Yorkshire, UK
- Age at study initiation: juveniles (from stock maintained in-house since March 15 2017)
- Length at study end: 5.6 cm (sd = 0.37)
- Weight at study end: 1.5 g (sd = 0.33)
- Maintenance of the stock fish: in a glass fiber tank with a "single pass" water renewal system

ACCLIMATION
- Acclimation period: 7 days
- Acclimation conditions: same as test conditions ( at 14 -15 °C ; dissolved oxygen content ≥ 9.6 mg O2/L.
- Type of food during acclimation: commercial trout pellets
- Feeding frequency during acclimation: no data
- Health during acclimation: no mortality

FEEDING DURING TEST: none (witheld from 24 h prior to exposure start)

Test type:

semi-static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

96 h

Hardness:

140 mg/L as CaCO3

Test temperature:

14-15 °C

pH:

7.8-8.2

Dissolved oxygen:

10.1-10.8 mg/L in fresh solutions (100-107% of saturation)
9.3-9.7 mg/L in old solutions (90-96% of saturation)

Salinity:

NA

Nominal and measured concentrations:

nominal: 0 and 98 mg/L
measured: at 0 mg/L < LOQ; at 98 mg/L 98-99% of nominal (in fresh solutions at 0 and 72 hours and in old solutions at 24 and 96 hours)

Details on test conditions:

TEST SYSTEM
- Test vessel: 25-30 L glass aquaria with 20 L test medium
- Type: closed
- Aeration: yes via narrow bore glass tubes
- Renewal rate of test solution: every 24 hours
- No. of organisms per vessel: 7
- No. of vessels per concentration (replicates): 1
- No. of vessels per control (replicates): 1
- No. of vessels per vehicle control (replicates): NA
- Biomass loading rate: 0.51 g/L

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: dechlorinated and softened tap water

OTHER TEST CONDITIONS
- Adjustment of pH: none
- Photoperiod: 18 h light/ 6 h dark
- Light intensity: NA

EFFECT PARAMETERS MEASURED : mortalities and sub-lethal effects of exposure were recorded at 1, 3, 6, 24, 48, 72 and 96 hours after the start of exposure

TEST CONCENTRATIONS
- Range finding study: NA
- Test concentrations: 0 and 98 mg/L
- Results used to determine the concentrations for the definitive study: limit test based on the outcome of the acute dapnia test and lemna test according to the threshold approach as indicated in the REACH guidance

VALIDITY CRITERIA:
- 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 in the control and test vessels.

Key result

Duration:

96 h

Dose descriptor:

LC50

Effect conc.:

> 98 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality (fish)

Remarks on result:

other:

Remarks:

measured concentrations were within 80-120% of nominal

Details on results:

No mortality was observed at 0 and 98 mg/L at any of the observation times. At 98 m/L a slight staining on the fins and around the mouth was observed at all observation times

Validity criteria fulfilled:

yes

Conclusions:

The LC50 of the substance is > 98 mg/L

Executive summary:

In a test according to OECD 203 (semi static with renewal every 24 hours), 7 rainbow trouts/concentration were exposed during 96 hours to 0 and 98 mg/L of the substance. The measured concentrations were between 98 and 99% of nominal. No mortality was observed at 1, 3, 6, 24, 48, 72 and 96 hours after the start of exposure in controls and at 98 mg/L. A slight staining on the fins and around the mouth was observed in fish exposed at 98 mg/L. The LC50 is therefore > 98 mg/L.

Description of key information

In a test according to OECD 203 (semi static with renewal every 24 hours, Envigo 2017), 7 rainbow trouts/concentration were exposed during 96 hours to 0 and 98 mg/L of the substance. The measured concentrations were between 98 and 99% of nominal. No mortality was observed at 1, 3, 6, 24, 48, 72 and 96 hours after the start of exposure in controls and at 98 mg/L. A slight staining on the fins and around the mouth was observed in fish exposed at 98 mg/L. The LC50 is therefore > 98 mg/L.

Key value for chemical safety assessment

Fresh water fish

Fresh water fish

Effect concentration:

98 mg/L

Additional information

This value is similar to the LC50 of > 100 mg/L found in a test by Bayer (1988).