4'-aminoazobenzene-4-sulphonic acid

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:

weight of evidence

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

data from handbook or collection of data

Remarks:

experimental data from various test chemicals

Justification for type of information:

Experimental data of test chemical

Reason / purpose for cross-reference:

read-across source

Reason / purpose for cross-reference:

read-across source

Qualifier:

according to guideline

Guideline:

other: Refer below principle

Principles of method if other than guideline:

WoE report is prepared based on short term toxicity to aquatic invertebrates study:
2 and 3 reports

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

2: The stock solution 200 mg/L was prepared by dissolving light grey powder in reconstituted water. The test solutions of required concentrationas were prepared by mixing the stock solution of the test sample with reconstituted test water.
3rd: The stock solution 100 mg/l was prepared by dissolving yellow powder in reconstituted water.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Water flea
- Strain: Straus
- Justification for species other than prescribed by test guideline:
- Source: Own breeding at University of Chemistry and Technology, Prague
- Age of parental stock (mean and range, SD): The animals used for the test shall be less than 24 h old and should not be first brood progeny
- Feeding during test: No feeding

Test type:

static

Water media type:

freshwater

Total exposure duration:

48 h

Remarks on exposure duration:

2nd study: ± 1 hr

Test temperature:

20±1°C

pH:

2nd: Test: 6.9 (changed to 7.4 during test)
Control 1 : 7.6 (changed to 7.4)
Control 2 : 7.7 (No change during the test)
Control 3 : 7.7 (changed to 7.6)

3rd study: Test: 7.9 (changed to 7.7 during test)
Control: 8.0 (Change to 7.8 during test)

Dissolved oxygen:

2nd: higher than 7.8 mg/L at the end of test
3rd: higher than 8.4 mg/L at the end of test

Nominal and measured concentrations:

2nd: 0, 5, 10, 25, 50, 100, 200 mg/l
3rd: Limit concentration 100 mg/l were used.

Details on test conditions:

2nd study: TEST SYSTEM
- Test vessel: 50 ml glass vessel
- fill volume: 25 ml
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4

3rd:
TEST SYSTEM
- Test vessel: 50 ml glass vessel
- fill volume: 25 ml
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 5

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water:
Natural water (surface or ground water), reconstituted water or dechlorinated tap water are acceptable as culturing and dilution water if D. magna survives in it for the duration of the culturing, acclimation and testing without showing signs of stress. Waters in the range pH 6 to pH 9, with hardness between 140 mg/l and 275 mg/l (as CaCO3) are recommended.
As an example, the preparation of dilution water meeting the requirements is described below.
Dissolve known quantities of reagents in water. The dilution water prepared shall have a pH of 7.8 ± 0.5, a hardness of (225 ± 50) mg/l (expressed as CaCO3), a molar Ca + Mg ratio close to 4 + 1 and a dissolved oxygen concentration above 7 mg/l.

Prepare the solutions specified below:
- Calcium chloride solution: Dissolve 117.6 g of calcium chloride dihydrate (CaCl2.2H2O) in water (4.2) and make up to 1 l with water (4.2).
- Magnesium sulfate solution: Dissolve 49.3 g of magnesium sulfate heptahydrate (MgSO4.7H2O) in water (4.2) and make up to 1 l with water (4.2).
- Sodium bicarbonate solution: Dissolve 25.9 g of sodium bicarbonate (NaHCO3) in water (4.2) and make up to 1 l with water (4.2).
- Potassium chloride solution: Dissolve 2.3 g of potassium chloride (KCI) in water (4.2) and make up to 1 l with water (4.2).

Mixing
Mix 2.5 ml of each of the four solutions and make up to 1 l with water.
The dilution water shall be aerated until the dissolved oxygen concentration has reached saturation and the pH has stabilized. If necessary, adjust the pH to 7.8 ± 0.5 by adding sodium hydroxide (NaOH) solution or hydrochloric acid (HCI). The dilution water prepared in this way shall not be further aerated before use.

- Sodium hydroxide solution, e.g. [NaOH] : 1 mol/l.
- Hydrochloric acid, e.g. [HCl] : 1 mol/l.

Reference substance:
Dissolve 600 mg of potassium dichromate (K2Cr2O7) in water and make up to 1 l with water (4.2).

OTHER TEST CONDITIONS
- Adjustment of pH: no adjustment done
- Photoperiod: No - Darkness
- Light intensity:

CALCULATION:
EC50 was calculated using non linear regression by the software Prism 4.0

Reference substance (positive control):

yes

Remarks:

Potassium dichromate (K2Cr2O7)

Key result

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

500 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 2nd study

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

> 100 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 3rd study

Results with reference substance (positive control):

2nd: - Results with reference substance valid
- EC50: 0.79 mg/L (24 hours)

3rd: - Results with reference substance valid
- EC50: 0.76 mg/L (24 hours)

Reported statistics and error estimates:

2nd: EC50 or 48 h EC50 calculated by non-linear regression using software Prism 4.0, GraphPad.

Validity criteria fulfilled:

no

Conclusions:

2nd: The median effective concentration (EC50) for the test substance, in Daphnia magna was determined to be 500 mg/L on the basis of mobility inhibition effects in a 48 hour study.
3rd: The effect concentration (EC50) for the test substance, in Daphnia magna was determined to be > 100 mg/L on the basis of mobility inhibition effects in a 48 hour study. Only 4% inhibition was determine after 48 hrs of exposure.
Thus based on the all above studies and effects, test chemical consider to be nontoxic to the aquatic invertebrates and hence not classified as per the CLP classification criteria.

Executive summary:

Various short term studies available for the test chemical were reviewed to determine the toxic nature of test chemical on the mobility of aquatic invertebrates. The studies are as mentioned below:

Aim of this study was to access the short term toxicity of test chemical to aquatic invertebrate daphnia magna. Study was performed according to the OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test) in a static system for the total exposure period of 48 hrs. The stock solution 200 mg/L was prepared by dissolving light grey powder in reconstituted water. The test solutions of required concentration as were prepared by mixing the stock solution of the test sample with reconstituted test water. 0, 5, 10, 25, 50, 100, 200 mg/l nominal concentrations were used in the study. Effects on immobilisation were observed for 48 hours. With the test substance one positive control Potassium dichromate (K2Cr2O7) was also run simultaneously. After the exposure of chemical, effect concentration EC50 was calculated using nonlinear regression by the software Prism 4.0. The median effective concentration (EC50) for the test substance, in Daphnia magna was determined to be 500 mg/L on the basis of mobility inhibition effects in a 48 hour study. Based on the EC50 value, it indicates that the substance is likely to be non-hazardous to aquatic invertebrates and cannot be classified as per the CLP criteria.

First study was supported by the second study from experimental report. Aim of the study was to determine the short term toxicity of test chemical to aquatic invertebrates by performing test according to the OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test) in a static system. The stock solution 100 mg/l was prepared by dissolving yellow powder in reconstituted water. Effects on immobilisation were observed for 48 hours. With the test substance one positive control Potassium dichromate (K2Cr2O7) was also run simultaneously. After the exposure of chemical, effect concentration EC50 was calculated using nonlinear regression by the software Prism 4.0. 25 daphnia magna were used in the study, out of that only 1 daphnia magna shows immobility and the remaining were mobile. The effect concentration (EC50) for the test substance, in Daphnia magna was determined to be > 100 mg/L on the basis of mobility inhibition effects in a 48 hour study. Only 4% inhibition was determine after 48 hrs of exposure. Based on the inhibitory concentration chemical was consider as nontoxic and not classified as per the CLP classification criteria.

Thus based on the all above studies and effects, test chemical consider to be nontoxic to the aquatic invertebrates and hence not classified as per the CLP classification criteria.

Description of key information

2nd: The median effective concentration (EC50) for the test substance, in Daphnia magna was determined to be 500 mg/L on the basis of mobility inhibition effects in a 48 hour study.

3rd: The effect concentration (EC50) for the test substance, in Daphnia magna was determined to be > 100 mg/L on the basis of mobility inhibition effects in a 48 hour study. Only 4% inhibition was determine after 48 hrs of exposure.

Thus based on the all above studies and effects, test chemical consider to be nontoxic to the aquatic invertebrates and hence not classified as per the CLP classification criteria.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

500 mg/L

Additional information

Various short term studies available for the test chemical and structurally and functionally similar read across chemical were reviewed to determine the toxic nature of test chemical on the mobility of aquatic invertebrates. The studies are as mentioned below:

Aim of this study was to access the short term toxicity of test chemical to aquatic invertebrate daphnia magna. Study was performed according to the OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test) in a static system for the total exposure period of 48 hrs. The stock solution 200 mg/L was prepared by dissolving light grey powder in reconstituted water. The test solutions of required concentration as were prepared by mixing the stock solution of the test sample with reconstituted test water. 0, 5, 10, 25, 50, 100, 200 mg/l nominal concentrations were used in the study. Effects on immobilisation were observed for 48 hours. With the test substance one positive control Potassium dichromate (K2Cr2O7) was also run simultaneously. After the exposure of chemical, effect concentration EC50 was calculated using nonlinear regression by the software Prism 4.0. The median effective concentration (EC50) for the test substance, in Daphnia magna was determined to be 500 mg/L on the basis of mobility inhibition effects in a 48 hour study. Based on the EC50 value, it indicates that the substance is likely to be non-hazardous to aquatic invertebrates and cannot be classified as per the CLP criteria.

 

 

Above study was supported by the second study from experimental report. Aim of the study was to determine the short term toxicity of test chemical to aquatic invertebrates by performing test according to the OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test) in a static system. The stock solution 100 mg/l was prepared by dissolving yellow powder in reconstituted water. Effects on immobilisation were observed for 48 hours. With the test substance one positive control Potassium dichromate (K2Cr2O7) was also run simultaneously. After the exposure of chemical, effect concentration EC50 was calculated using nonlinear regression by the software Prism 4.0. 25 daphnia magna were used in the study, out of that only 1 daphnia magna shows immobility and the remaining were mobile. The effect concentration (EC50) for the test substance, in Daphnia magna was determined to be > 100 mg/L on the basis of mobility inhibition effects in a 48 hour study. Only 4% inhibition was determine after 48 hrs of exposure. Based on the inhibitory concentration chemical was consider as nontoxic and not classified as per the CLP classification criteria.

 

Thus based on the all above studies and effects, test chemical consider to be nontoxic to the aquatic invertebrates and hence not classified as per the CLP classification criteria.