Disodium 2,5-dichloro-4-[4-[[5-[[(dodecyloxy)carbonyl]amino]-2-sulphonatophenyl]azo]-4,5-dihydro-3-methyl-5-oxo-1H-pyrazol-1-yl]benzenesulphonate

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)

Version / remarks:

adopted 1984

GLP compliance:

not specified

Details on test solutions:

- Appearance: clear, yellow solution.
- Preparation: test item was dissolved in the test medium at a concentration of 100 mg/100 ml (stock solution). Thereafter, series of sequential dilutions with the test medium were prepared to obtain the flnal test concentrations of the test article.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Source: the animals were bred in the testing laboratories of under standardized conditions.
- Age of animals: for the tests, animals with an age of less than 24 hours were used.

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

24 h

pH:

Start: 8.4
End: 8.3

Dissolved oxygen:

Start: 8.5 mg/l
End: 8.7 mg/l

Nominal and measured concentrations:

1, 10 and 100 mg/l, nominal

Details on test conditions:

TEST SYSTEM
- Test vessel: 50 ml beakers containing 20 ml of test medium.
- No. of organisms per vessel: 10 animals.
- No. of vessels per concentration: 2 replicates.
- No. of vessels per control: 2 replicates.

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: the test medium used was prepared according to the Directive EEC. The water used was bi-distilled water.
- CaCl2 × 2H2O: 294 mg/l
- MgSO4 × 7 H2O: 123 mg/l
- NaHCO3: 65 mg/l
- KCl: 5.8 mg/l

OTHER TEST CONDITIONS
- Adjustment of pH: adjusted to 7.9 ± 0.3.
- Photoperiod: 16 hours of illumination.
- Light intensity: 1000 Lux.

EFFECT PARAMETERS MEASURED
Test evaluations were done according to the OECD guideline 202 by visual control of the mobility of the daphnids after 24 hours.

VALIDITY OF THE TEST
The validity of the test was proven by determining the mortality of the control animals tested under the same conditions.

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

EC0 (24h): 10 - 100 mg/l (nominal)
EC100 (24h) > 100 mg/l (nominal)

Influence of test item on the immobilization of Daphnia magna.

Vessel	No animals	No of response	% of response
Control	10	0	0
Control	10	0	0
Test item 1 mg/l	10	0	0
Test item 1 mg/l	10	1	10
Test item 10 mg/l	10	0	0
Test item 10 mg/l	10	0	0
Test item 100 mg/l	10	1	10
Test item 100 mg/l	10	2	20

Conclusions:

EC50 (24h) > 100 mg/l (nominal)

Executive summary:

The toxicity study was run using the species Daphnia magna. The daphnids were exposed over a period of 24 hours to the test article in 20 ml beakers containing 20 ml test medium per 10 animals. All tests were run in duplicate. The concentrations tested were 0, 1, 10 and 100 mg/l nominal.

10 % of daphnids resulted to be immobilized after 24 hours in one of the vessels containing 1 mg/l; at the concentration of 10 mg/l, no immobilization was recorded; at 100 mg/l, 10 and 20 % of immobilization was recorded.

Conclusion

EC50 (24h) > 100 mg/l (nominal)

Description of key information

EC50 (24h) > 100 mg/l, nominal

Additional information

The toxicity potential of Acid Yellow 218 to invertebrates was assayed in Daphnia magna. The daphnids were exposed over a period of 24 hours to the test artlcle nominal concentrations of 0, 1, 10 and 100 mg/l. 10 % of daphnids resulted to be immobilized after 24 hours in one of the vessels containing 1 mg/l; at the concentration of 10 mg/l no immobilization was recorded; while at 100 mg/l 10 and 20 % of immobilization was recorded.