Sodium 6-amino-5-[[2-[(ethylphenylamino)sulphonyl]phenyl]azo]-4-hydroxynaphthalene-2-sulphonate

Short-term toxicity to aquatic invertebrates

Link to relevant study record(s)

Reference

Endpoint:

short-term toxicity to aquatic invertebrates

Type of information:

read-across from supporting substance (structural analogue or surrogate)

Adequacy of study:

key study

Study period:

June from 02nd to 22nd, 2014

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with generally accepted scientific standards and described in sufficient detail

Justification for type of information:

Justification for read across apporach is detailed in the report attached to the IUCLID section 13

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Version / remarks:

13 April 2004

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Analytical monitoring:

yes

Details on sampling:

Analytical samples were taken and analysed from 100 mg/l and control at test start (fresh) and after 48 hours (aged).

Details on test solutions:

The necessary amount of test item for preparing the test solution was weighed on weighing scoops and transferred to a volumetric flask.
Test medium was added up to the bench mark and the solution was homogenised by shaking. 50 ml of the prepared solution was transferred to each test vessel.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Strain/clone: Daphnia magna Straus, Clone V.
- Source: the animals are continuously bred in the laboratory and were originally purchased in a healthy condition from the Umweltbundesamt (Federal Environment Agency) in Berlin/Germany.
- Age of parental stock: freshly hatched daphnids less than 24 hours old were used for the test.
- Feeding during test: none.
- Food: fed with single cell green algae (Desmodesmus subspicatus, formerly Scenedesmus subspicatus).
- Frequency: at least three times a week.

BREEDING CONDITIONS
- Medium: organisms were bred as group culture (5 to 20 daphnids per litre) in Elendt M4 medium.
- Temperature: daphnids were reared at 20 ± 2 °C in a climatic chamber.
- pH: aerated water was within a range of 6.0 – 9.0.
- Dissolved oxygen: above 60 % saturation.
- Total hardness 140 - 250 mg/l (as CaCO3), corresponding to 7.8 - 14°dH.
- Photoperiod: 16 hours of illumination and 8 hours of darkness.
- Renewal of the medium: the medium was changed three times per week. A pipette was used to separate the young daphnids from the adults.

Test type:

static

Water media type:

freshwater

Limit test:

yes

Total exposure duration:

48 h

Test temperature:

20.6 ± 0.2 °C

Dissolved oxygen:

8.8 ± 0.1 mg/l

Nominal and measured concentrations:

100 mg/l

Details on test conditions:

TEST SYSTEM
- Test vessel: four 100 ml glass beakers per concentration, each filled with 50 ml, one additional replicate for measurements without test organisms.
- Aeration: none.
- No. of organisms per concentration: 20.
- No. of vessels per concentration: 4 replicates of 5 animals each.
- No. of vessels per control: 4 replicates.
- No. of vessels per reference substance: 1 replicate.
- Loading rate: 10 ml of test solution for each animal.

TEST MEDIUM / WATER PARAMETERS
- Test medium: Elendt M4 medium.
- pH: at test initiation the pH-value of the control (untreated test medium) was 7.96.
- Dissolved oxygen: at test initiation the concentration in the control was 8.9 mg/l.
- Total hardness: at test initiation total hardness in the control was 13°dH (232 mg/l as CaCO3).

OTHER TEST CONDITIONS
- Photoperiod: 16 hours photoperiod /8 hours darkness daily.

EFFECT MEASURED
After 24 h and 48 h, immobilised daphnids were counted. All daphnids not able to swim within 15 s after gentle agitation of test vessel were considered to be immobilised. If present, behavioural changes of daphnids were recorded at 24 and 48 h after starting the test.
The NOEC was established based on the highest concentration at which the immobilisation is not higher than the allowed control immobilisation (± 10 % immobilisation).

MEASUREMENTS
Test temperature and pH-value as well as oxygen saturation rate of test solutions were measured at all concentrations at t = 0 h from fresh test solutions and after 24 h and 48 h from aged test solutions in one separate replicate per test item concentration without test organisms.

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mortality

Details on results:

No immobilisation was recorded over the observation period of 48 hours.

MEASURED CONCENTRATIONS
The fresh measured concentration of test item at 100 mg/l was 97 % of nominal and the aged measured concentration was 95 %.

Results with reference substance (positive control):

EC50 (24h): between 1.0 and 2.0 mg/l.

Reported statistics and error estimates:

No statistical evaluation was indicated since no immobilisation occurred at the limit test concentration of 100 mg/l.

IMMOBILIZATION

Overall of results

Concentration	N. immobilized daphnids		% of immobilization
	24 hrs	48 hrs	24 hrs	48 hrs
Control	0	0	0	0
Control	1*	1*	0	0
Control	0	0	0	0
Control	0	0	0	0
Test item 100 mg/l	0	0	0	0
Test item 100 mg/l	0	0	0	0
Test item 100 mg/l	0	0	0	0
Test item 100 mg/l	0	0	0	0

*died by accident

Reference substance

Concentration	N. immobilized daphnids		% of immobilization
	24 hrs	48 hrs	24 hrs	48 hrs
K2Cr2O7 1.0 mg/l	0	1	0	10
K2Cr2O7 1.0 mg/l	1	1	10	10
K2Cr2O7 1.0 mg/l	0	0	0	0
K2Cr2O7 1.0 mg/l	0	0	0	0
K2Cr2O7 2.0 mg/l	5	5	100	100
K2Cr2O7 2.0 mg/l	4	5	80	100
K2Cr2O7 2.0 mg/l	5	5	100	100
K2Cr2O7 2.0 mg/l	4	5	80	100

MEASURED CONCENTRATIONS

	Sampling (h)	Test item found
		mg/l	% of nominal
Control	0 fresh	n.d.	-
	48 aged	n.d.	-
Test item	0 fresh	97	97
	48 aged	95	95

Validity criteria fulfilled:

yes

Remarks:

in the control not more than 10 % of animals were immobilised and the dissolved oxygen concentration was ≥ 3 mg/l at the end of the test in control and test vessels

Conclusions:

EC50 (48 h) > 100 mg/l (nominal)

Executive summary:

Test item short-term toxicity to aquatic invertebrates was assessed using Daphnia magna, according to the OECD guideline 202. Twenty organisms per test concentration (4 replicates of 5 animals each) were used. The duration of the test was 48 hours. A static limit test with concentrations of 0 and 100 mg/l was performed. Analytical samples taken at 0 hours (initial value) from fresh test solutions and after 48 hours from aged test solutions were analysed from control and 100 mg/l. The initial measured content at 100 mg/l was 97 % of nominal and the aged measured content was 95 % of nominal. Therefore the toxicological endpoints were evaluated using nominal concentrations. After the 48 hours exposure period, no immobilisation was recorded at 100 mg/l, thus this concentration can be considered as a No Observed Effect Concentration.

Conclusion

EC50 (48 h) > 100 mg/l (nominal)

Description of key information

EC50 (48 h) > 100 mg/l (nominal)

Additional information

There are no information about the short-term toxicity potential to aquatic invertebrates of Acid Red 057, thus the available data on structural analogous Similar Substance 01 has been taken into account. The read across approach can be considered as reliable and suitable for the purpose; details and explanations are included in the report attached to the IUCLID section 13.

Similar Substance 01 was assessed using Daphnia magna, according to the OECD guideline 202. A static limit test with concentrations of 0 and 100 mg/l was performed. Analytical samples taken at 0 hours (initial value) from fresh test solutions and after 48 hours from aged test solutions were analysed from control and 100 mg/l: the initial measured content at 100 mg/l was 97 % of nominal and the aged measured content was 95 % of nominal. Therefore, the toxicological endpoints were evaluated using nominal concentrations. After the 48 hours exposure period, no immobilisation was recorded at 100 mg/l.