2,4-Imidazolidinedione, 5-(2-methylpropylidene)-, (5Z)-

Short-term toxicity to aquatic invertebrates

Administrative data

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

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

2003

Report date:

2003

Materials and methods

Test guideline

Test guideline 1

Qualifier:

according to guideline

Guideline:

OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)

Deviations:

no

Test guideline 2

Qualifier:

according to guideline

Guideline:

EU Method C.2 (Acute Toxicity for Daphnia)

Deviations:

no

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

(5Z)-5-(2-methylpropylidene)imidazolidine-2,4-dione

EC Number:

700-726-4

Cas Number:

1369499-44-4

Molecular formula:

C7H10N2O2

IUPAC Name:

(5Z)-5-(2-methylpropylidene)imidazolidine-2,4-dione

Sampling and analysis

Analytical monitoring:

yes

Test solutions

Details on test solutions:

For the preparation of a stock solution, 2.04 g/I of the test item were equilibrated in synthetic fresh water without NaHC03 and stirred for about 24 hours. The resulting solution was used as stock solution.

Test organisms

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia magna (Strauss)
- Method of breeding: For breeding, the females are maintained in M4 medium in 1 L beakers. A reddish dark-brown coloration of the animals
indicates that they are healthy. At two to three day intervals, the exuviae are syphoned off and the water is changed. In the course of this, the
offspring is removed from the breeding vessels. At regular intervals of approximately 4 weeks, offspring is isolated from the vessels. They serve as a basis for further breeding. The culture conditions ensure parthenogenetic reproduction.
- Feeding during test: The daily amount of food is such that the amount added is consumed by the animals.
- Food type: algae (Desmodesmus subspicatus)

Study design

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

48 h

Test conditions

Hardness:

14°dH

Test temperature:

20.5-20.9°C (mean: 20.8°C)

pH:

7.4-7.8

Dissolved oxygen:

6.9-8.6 mg/L

Nominal and measured concentrations:

nominal: 61, 91, 122, 182, 253, 354, 506, 709 and 1013 mg/L

Details on test conditions:

TEST SYSTEM
- Test vessel: Round-bottom test tubes calibrated to 10 mL
- Aeration: no
- No. of organisms per vessel: 20 organisms in 4 parallel sets of 5 each
- No. of vessels per concentration (replicates): 9 test item concentrations
- No. of vessels per control (replicates): 1 control

TEST MEDIUM / WATER PARAMETERS
compoundl parameter concentration (mgl L)
CaCI2 x 2 H20 294
MgS04 x 6 H20 114
NaHC03 65
KCI 6
sum of Ca2+ - and Mg2+ -ions 2.5 mmol
proportion of Ca2+ - : Mg2+ -ions (mol) 4:1
proportion of Na+- : K+-ions (mol) 10:1
water hardness 14°dH = 250 mg CaC03/ L

OTHER TEST CONDITIONS
Light/dark cycle: dark
Temperature: 20.5 - 20.9°C (mean: 20.8°G)
Aeration: none
Feeding: none
Solubilizer: none

Reference substance (positive control):

yes

Remarks:

potassium dichromate

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

48 h

Dose descriptor:

EC0

Effect conc.:

122 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 2

Duration:

48 h

Dose descriptor:

EC50

Effect conc.:

255 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Effect concentrations 3

Duration:

48 h

Dose descriptor:

EC100

Effect conc.:

506 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

The analytical verification of the test item concentrations was carried out after 0 and 48 hours.
The measured test concentrations after 48 h did not deviate by more than 20% from the freshly prepared test solutions. It can be concluded that the test item was present during the whole exposure time. Therefore, the nominal values of the test item concentrations were used for the evaluation of the test.

Results with reference substance (positive control):

Influence of potassium dichromate on the swimming behaviour after 24 hexposure:
1.0 mg/L 45% of immobilised Daphnia
2.0 mg/L 100% of immobilised Daphnia

Applicant's summary and conclusion

Validity criteria fulfilled:

yes

Conclusions:

The EC50 value for immobilisation after 48h by the test item is 255 mg/L.