Octasodium 2-(6-(4-chloro-6-(3-(N-methyl-N-(4-chloro-6-(3,5-disulfonato-2-naphthylazo)-1-hydroxy-6-naphthylamino)-1,3,5-triazin-2-yl)aminomethyl)phenylamino)-1,3,5-triazin-2-ylamino)-3,5-disulfonato-1-hydroxy-2-naphthylazo)naphthalene-1,5-disulfonate

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 Septemeber 27, 1993 to September 29, 1993

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

GLP compliance:

yes

Specific details on test material used for the study:

Purity: 66.9% w/w
Batch number: NBY 35071/15
Physical state: solid
Color: orange/red

Analytical monitoring:

yes

Details on sampling:

The concentration of test substance in the test solutions was measured at the start and end of the test using the method. At the start of the test the remaining excess of the test solutions was sampled and analysed. At the end of the test each of the replicates of the test solutions were sampled and analysed.

Vehicle:

no

Details on test solutions:

A nominal 180 mg/L solution of the test substance was prepared by dissolving 0.1806 g of test substance in 1 L of dilution medium. The resultant solution was clear and bright orange in color.

The following nominal exposure concentrations were employed:
Control and 180 mg/l.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Fresh water crustacean
- Strain/clone: Daphnia magna
- Food type: Chlorella vulgaris and "Frippak Booster" (a commercially available microencapsulated diet)

Conditions:
-Temperature: 20 ± 2°C
-Photoperiod: 16 h light/ 8 h dark

The Daphnia were not fed during the course of the test

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test temperature:

20 ± 1°C

pH:

8.38 to 8.48

Dissolved oxygen:

8.8 to 9.0 mg/L

Nominal and measured concentrations:

The mean measured concentration of test substance was 106% of the nominal value of 180 mg/L.

Details on test conditions:

Borosilicate glass beakers of 250 mL capacity were used as test vessels, with four replicates per exposure concentration. Each vessel contained 200 mL of test solution providing a depth of approximately 60 mm. The beakers were covered with loose fitting lids. The test was initiated by adding five Daphnia to each vessel, in <2 mL of dilution water, giving a total of 20 Daphnia per concentration. The test solution temperature was maintained at 20 ± 1°C by control of the room temperature and a photoperiod of 16 hours light and 8 hours dark, with 15 minute transition periods, was provided. The test solutions were not aerated.

The concentrations of analytical grade chemicals used to prepare the medium in glass-distillated water were as follows:
NaHCO3 (mg/L) 192
CaSO4.2H20 (mg/L) 120
MgSO4.7H20 (mg/L) 245
KCl (mg/L) 8

Reference substance (positive control):

no

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 180 mg/L

Nominal / measured:

meas. (arithm. mean)

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

The numbers of Daphnia immobilized at each concentration, after 24 and 48 hours, are provided in table in other information on results.

The EC50 values obtained were:
24 hours >180 mg/L
48 hours >180 mg/L

Acute toxicity to Daphnia magna

Time (h)	Nominal concentration (mg/L)	Number immobilised per replicate				Total number tested	Total number immobilised	% immoboilised
		A	B	C	D
24	control	0	0	0	0	20	0	0
	180	0	0	0	0	20	0	0
48	control	0	0	0	0	20	0	0
	180	0	0	0	0	20	0	0

Acute toxicity to Daphnia magna: analytical results

Nominal concentration (mg/L)	Measured concentration (mg/L)		Mean measured concentration over the test duratrion (mg/L)	Mean measured concetration as % of nominal *
	0 hour	48 hours
Control	<0.42	<0.42	<0.42	-
180	180	190	190	106%

*  Mean of individual determinations on each replicate test solution at the end of the test; the individual values were 180, 180, 190 and 190 mg/L respectively.

Validity criteria fulfilled:

yes

Conclusions:

Under the study conditions, the mean measured 48 h EC50 of the substance in Daphnia magna was determined to be greater than 180 mg/L.

Executive summary:

A study was conducted to determine the acute toxicity of the substance to Daphnia magna according to OECD Guideline 202 and EU method C.2, in compliance with GLP. 20 daphnids were exposed to the test substance at a nominal concentration of 180 mg/L for 48 h under static conditions. Immobility was determined at 24 and 48 h. Analytical dose verification was conducted. Under the study conditions, the mean measured 48 h EC50 of the substance in Daphnia magna was determined to be greater than 180 mg/L (Comber, 1993).

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

180 mg/L

Additional information

A study was conducted to determine the acute toxicity of the substance to Daphnia magna according to OECD Guideline 202 and EU method C.2, in compliance with GLP. 20 daphnids were exposed to the test substance at a nominal concentration of 180 mg/L for48 h under static conditions. Immobility was determined at 24 and 48 h. Analytical dose verification was conducted.Under the study conditions, the mean measured 48 h EC50 of the substance in Daphnia magna was determined to be greater than 180 mg/L (Comber, 1993).