Reaction Mass of disodium [(E)-7-nitro-3-oxido-4-((2-oxidonaphthalen-1-yl)diazenyl)naphthalene-1-sulfonate) (E)-1-((3,5-dinitro-2-oxidophenyl)diazenyl)naphthalen-2-olate) chromate(2-)] and Hydrogen [(E)-7-nitro-3-oxido-4-((2-oxidonaphthalen-1-yl)diazenyl)naphthalene-1-sulfonate)(E)-1-((3,5-dinitro-2-oxidophenyl)diazenyl)naphthalen-2-olate) chromate(2-)]

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

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

guideline study with acceptable restrictions

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

yes (incl. QA statement)

Test organisms (species):

Daphnia magna

Details on test organisms:

The daphnia were bred in the testing facility of the Product Ecology TF, Textile Dyes Division under standardised conditions.Breeding :Cultures of Daphnia magna are maintained in glass vessels containing aprox. 3.0 I of reconstituted water, at 18 - 22°C. The water was renewed partially three times weekly. The daphnia were feed with a suspension of green algae (Scenedesmus subspicatus) supplemented by a suspension of TETRAMIN-extract in such quantités that the food was consumed within 24h.Pretreatment :24 hours before the start of the exposure reproductive daphnia were separated from the young daphnia by sieving all individuals through a 710 um sieve. The quality of the daphnia is checked at least every 3 months by determining the EC50 values (24 h) for potassium dichromate (range: 0.8 -1.5 mg/l). For each concentration, of test substance, 20 daphnia divided in two groups of 10 animals are used.

Hardness:

136 mg/l CaCO3

Test temperature:

21°C

pH:

7.8-8.2

Dissolved oxygen:

Saturation of oxygen, 96-99%

Nominal and measured concentrations:

58, 200 and 180 mg/l as nominal concentrations corresponding to 2.9, 5.5 and 10 mg/l measured concentrations.1 g Test substance were mixed with 200 ml test medium and fill up to 1000 ml with test medium. The stock solution was homogenized for five minutes in the supersonic bath. Since the test substance was only poorly soluble in water, most of the test substance settled down and built a sediment at the bottem of the flask.For the preparation of the test solutions only the supernatant of the stock solution was taken.

Details on test conditions:

48 hours at 21 °C, 16 hours light / 8 hours dark. The daphnia were exposed to the test article in 250 ml beakers containing 100 - 200 mltest medium with 10 animals per beaker. All tests are run in duplicate. During exposure the animals were kept at 21 ± 1°C with 16 hours illumination.

Reference substance (positive control):

yes

Remarks:

potassium dichromate EC50 = 0.96 mg/l

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 10 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 10 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

mobility

Duration:

48 h

Dose descriptor:

EC0

Effect conc.:

> 10 mg/L

Nominal / measured:

meas. (initial)

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

no mortality was observed at any nominal (and measured) concentration.

Conclusions:

The test item was tested for acute toxicity to Daphnia Magna following OECD 202. Under the experimental conditions the EC50, 48h > 10 mg/l.

Executive summary:

The test item was tested for acute toxicity to Daphnia Magna following OECD 202. Two replicated each with 10 daphnis were tested for each concentration, nominally 58, 100 and 180 mg/l, which experimentally resulted equal to 3.0, 5.6 and 10.1 mg/l due to precipitation in the test medium. No immobilisation of the Daphnis was observed at any concentration after 24 and 48h. The EC0 and EC50, 48h is therefore > 10 mg/l.

Description of key information

Daphnia Magna, Acute toxicity, Ec50, 48h > 10 mg/l (equal to EC0, precipitation occured)

Additional information

One acute toxicity study on aquatic invertebrates, namely Daphnia Magna, is available for the analogue substance (Huntsman, 1993). During the experiment precipitation of the test item in the test medium occured and at the solubility limit of the test item under the experimental conditions the EC50, 48h is > 10 mg/l, which correspond to EC0 since no immobilisation was observed.

Based on the read across considerations the same results apply to Acid Black 107:1