9-(2-carboxyphenyl)-3,6-bis(diethylamino)xanthylium acetate

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:

weight of evidence

Reliability:

1 (reliable without restriction)

Rationale for reliability incl. deficiencies:

guideline study

Justification for type of information:

Experimental test result performed using standard test guideline

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

GLP compliance:

no

Analytical monitoring:

no

Vehicle:

no

Details on test solutions:

The stock solution 100 mg/L was prepared by dissolving red -violet liquid in reconstituted water. Test solutions of required concentrations were prepared by mixing the stock solution of the test substance in reconstituted water.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Water flea
- Strain: Straus
- Source: Own breeding at University of Chemistry and Technology, Prague
- Age at study initiation (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

ACCLIMATION - No data available

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Remarks on exposure duration:

± 1 hr

Test temperature:

20±1°C

pH:

Test at highest concentration: 7.9 (did not change during the test)
Control: 7.8 (changed to 7.9 during test)

Dissolved oxygen:

higher than 7.5 mg/L at the end of test

Nominal and measured concentrations:

0, 1, 2, 4, 8 and 16 mg/L

Details on test conditions:

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

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

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.:

10

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95 % CI: 6.3- 15.9

Results with reference substance (positive control):

- Results with reference substance valid
- EC50: 0.73 mg/L (24 hours)

Reported statistics and error estimates:

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

Validity criteria fulfilled:

yes

Conclusions:

The median effective concentration (EC50) for the test substance on Daphnia magna was determined to be 10.0 mg/L on the basis of mobility inhibition effects in a 48 hour study.

Executive summary:

Aim of this study was to assess the short term toxicity of test chemical to aquatic invertebrates 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 100 mg/L was prepared by dissolving red -violet liquid in reconstituted water. Test solutions of required concentrations were prepared by mixing the stock solution of the test substance in reconstituted water.

 

0, 1, 2, 4, 8 and 16 mg/L 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 10.0 mg/L on the basis of mobility inhibition effects in a 48 hour study. Based on the EC50 value, substance is likely to be hazardous to aquatic invertebrate and can be classified as aquatic chronic 2 as per the CLP classification criteria.

Description of key information

The median effective concentration (EC50) for the test substance in Daphnia magna was determined to be 10.0 mg/L on the basis of mobility inhibition effects in a 48 hour study. Based on the EC50 value, substance is likely to be hazardous to aquatic invertebrate and can be classified as aquatic chronic 2 as per the CLP classification criteria.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

10 mg/L

Additional information

Based on the experimental data for the target as well as read-across analogues which were functionally and structurally similar to the target chemical, toxicity of test chemical was determined on the basis ofimmobilization of aquatic invertebrates.The studies are summarized as below:

Aim of this study was to assess the short term toxicity of test chemical to aquatic invertebrates 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 100 mg/L was prepared by dissolving red -violet liquid in reconstituted water. Test solutions of required concentrations were prepared by mixing the stock solution of the test substance in reconstituted water.0, 1, 2, 4, 8 and 16 mg/L 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 10.0 mg/L on the basis of mobility inhibition effects in a 48 hour study. Based on the EC50 value, substance is likely to be hazardous to aquatic invertebrate and can be classified as aquatic chronic 2 as per the CLP classification criteria.

First study was further supported by second and third study as follows.

Aim of the second study was to assess the short term toxicity of test material to aquatic invertebrates 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 (100 mg/L) was prepared by dissolving pinkish red powder in reconstituted water. Concentrations used in the study were 0, 0.5, 1, 2, 3, 4 and 8 mg/L. Effects on immobilisation were observed for 48 hours. The median effective concentration (EC50) for the test substance, in Daphnia magna was determined to be 3.4 mg/L on the basis of mobility inhibition effects in a 48 hour study. Based on the EC50 value, substance is likely to be hazardous to aquatic invertebrate and can be classified as aquatic chronic 2 category as per the CLP classification criteria.

Again, a 24h study was conducted for determining the toxicity of test chemical on aquatic invertebrates, Thamnocephalus platyurus. Lethal concentration LC50 for 24h calculation was done with use of two methods – probit and graphical ones. LC50 for 24h (in mg/l) for T. platyurus was determined to be 8.06 mg/l.

 

Hence, from the above maximum values the test chemical is likely to be hazardous to aquatic invertebrates and can be classified as aquatic chronic 2 category as per the CLP classification criteria.