4-methyl-1-phenyl-3-pyrazolidone

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:

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)

Principles of method if other than guideline:

Short term toxicity of test chemical to aquatic invertebrates was performed according to the OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test) in a static system.

GLP compliance:

not specified

Analytical monitoring:

not specified

Vehicle:

yes

Details on test solutions:

The stock solution 20 mg/l was prepared by dissolving slightly yellow powder in reconstituted water. Test solutions of required concentrationas were prepared by mixing the stock solution of the test sample with reconstituted test 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
- Acclimation period:
- Acclimation conditions (same as test or not):
- Type and amount of food:
- Feeding frequency:
- Health during acclimation (any mortality observed):

Test type:

static

Water media type:

freshwater

Total exposure duration:

72 h

Remarks on exposure duration:

± 1 hr

Test temperature:

20±1°C

pH:

Test pH at higher concentration: 8 did not change during test
Control: 8 changes to 7.9 during the test

Dissolved oxygen:

higher than 8.7 mg/L at the end of test

Nominal and measured concentrations:

0, 0.5, 1, 2, 4 and 8 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
- 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:

72 h

Dose descriptor:

EC50

Effect conc.:

2.5 mg/L

Nominal / measured:

meas. (not specified)

Conc. based on:

test mat.

Basis for effect:

mobility

Remarks on result:

other: 95 % CI was 1.6-3.9 mg/l

Results with reference substance (positive control):

- Results with reference substance valid
- EC50: 0.76 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, in Daphnia magna was determined to be 2.5 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 substance 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 20 mg/l was prepared by dissolving slightly yellow powder in reconstituted water. Test solutions of required concentrationas were prepared by mixing the stock solution of the test sample with reconstituted test water. 0, 0.5, 1, 2, 4 and 8 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 2.5 mg/L on the basis of mobility inhibition effects in a 48 hour study. Based on the EC50 value, indicates that the substance is likely to be hazardous to aquatic invertebrates and can be be classified as aquatic chronic 2 category as per the CLP classification criteria.

Description of key information

Short-term toxicity to aquatic invertebrates:

Aim of this study was to assess the short term toxicity of test substance 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 20 mg/l was prepared by dissolving slightly yellow powder in reconstituted water. Test solutions of required concentrationas were prepared by mixing the stock solution of the test sample with reconstituted test water. 0, 0.5, 1, 2, 4 and 8 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 2.5 mg/L on the basis of mobility inhibition effects in a 48 hour study. Based on the EC50 value, indicates that the substance is likely to be hazardous to aquatic invertebrates and can be be classified as aquatic chronic 2 category as per the CLP classification criteria.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

2.5 mg/L

Additional information

Short-term toxicity to aquatic invertebrates:

Short-term toxicity to aquatic invertebrates was evaluated based on two experimental study report,

Aim of this study was to assess the short term toxicity of test substance 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 20 mg/l was prepared by dissolving slightly yellow powder in reconstituted water. Test solutions of required concentrationas were prepared by mixing the stock solution of the test sample with reconstituted test water. 0, 0.5, 1, 2, 4 and 8 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 2.5 mg/L on the basis of mobility inhibition effects in a 48 hour study. Based on the EC50 value, indicates that the substance is likely to be hazardous to aquatic invertebrates and can be be classified as aquatic chronic 2 category as per the CLP classification criteria.

In another study report ,daphnia sp., Acute Immobilization Test according to OECD Guideline 203 was conducted for test material. The test substance was soluble in water. Therefore, the test solution was prepared by dissolving 500 mg of the test substance in 500 ml of ADaM’s media. Achieving test concentrations of 1 g/L, respectively.

The nominal concentration selected for the experiment were 0.625 mg/L,1.25 mg/L, 2.5 mg/L, 5 mg/L, and 10 mg/L and test Daphnia magna were exposed to these concentration for 48 hours. The median lethal concentration (EC50) for test chemical on Daphnia magna in a 48 hours study on the basis of immobilization effect was found to be 0.625 mg/l.Thus, on the basis of this EC50 value and according to CLP criteria for aquatic classification of the substance, it is concluded that the substance exhibits short term toxicity to Daphnia.

After 48 hours of exposure to test item to nominal test concentrations, EC50 was determine to be 0.62mg/l . Based on the EC50, it can be consider that the chemical was and can be consider to be classified as aquatic acute 1 as per the CLP classification criteria.