trisodium 4-hydroxy-6-(sulfonatomethylamino)-5-(2-(2-sulfatoethylsulfonyl)phenylazo)naphthalene-2-sulfonate

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

experimental study

Adequacy of study:

key study

Study period:

From November 1997 to April 1998

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

GLP compliance:

yes

Analytical monitoring:

yes

Details on sampling:

The concentration control analytics were performed with the test substance solutions of the following nominal concentrations: 100, 12.5, 0 mg/L. At the start of the test (after 0 hours) samples from vessels without daphnids were analyzed. At the end of the test (after 48 h) samples from vessels with and without daphnids were analyzed.

Vehicle:

no

Details on test solutions:

Preparation of the stock solution and dilution:
The test substance was stirred in M4 medium for about 10 minutes at approximately 20 ± 1 °C. The nominal concentration of the stock solution eluate was 100 mg/L.
By dilution of this stock solution with M4 medium the following nominal concentrations were prepared:
100, 50, 25, 12.5 mg/L.

Test organisms (species):

Daphnia magna

Details on test organisms:

Daphnia magna STRAUS 1820. Supplier: Institut National de Recherche Chimique Appliquee, France.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test temperature:

20.9 - 21.7 °C

pH:

pH value: 7.9 - 8.0

Dissolved oxygen:

7.9 - 8.6 mg/L

Conductivity:

Conductivity: 550 - 650 µS/cm

Nominal and measured concentrations:

concentration range: 12.5 - 100 mg/L (dilution factor 2).

Details on test conditions:

Test volume: 10 mL
Loading (animals/mL): 0.5
Number of animals per vessel: 5
Total number of animals/conc.: 20
Number of replicates per concentration and per control: 4
Age of the animals: 2-24 hours
Age of stock animals: 2-4 weeks
Illumination: artificial light, type warm white (eg. OSRAM L58 W31); day: night rhythm 16:8
Check of the study and recording: visually after 0, 3, 6, 24 and 48 h

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC0

Effect conc.:

>= 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

Validity criteria were fulfilled:
- In the control the immobilization was ≤ 10 %
- In the control no Daphnids were captured in a surface film
- The O2 concentration was in all tested replicates .3mg/L
- The EC50(24h) of the control substance potassium dichromate was 1.25 mg/L

Results with reference substance (positive control):

The EC50(24h) of the control substance potassium dichromate was 1.25 mg/L

Validity criteria fulfilled:

yes

Conclusions:

Under the study conditions, the nominal 48-h EC50 was determined to be >100 mg/L.

Executive summary:

A study was conducted to determine toxicity of the test substance to the water flea (Daphnia magna) according to EU Method C.2, in compliance with GLP. For each test concentration, 20 Daphnia were exposed to the test substance for 48 h in a static test system. After 24 and 48 h, the immobilised Daphnia were counted. The substance was tested in the range of 12.5 to 100 mg/L. M4 medium served as negative control and potassium dichromate as positive control. The concentrations were analytically confirmed by spectrophotometry at 532 nm. Control analytics were performed with the test substance solutions of the following nominal concentrations: 100, 12.5 and 0 mg/L. At test start, samples from vessels without Daphnids were analysed. At the end of the test (after 48 h), samples from vessels with and without Daphnids were analysed. No toxicity was observed in any of the groups. The concentrations measured were in accordance with the expected nominal values. Under the study conditions, the nominal 48 hEC50 was > 100 mg/L and the 48 h NOEC was 100 mg/L (Maish, 1998).

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

100 mg/L