Succinimide

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

Study period:

20001-09-10 to 2001-05-07

Reliability:

2 (reliable with restrictions)

Rationale for reliability incl. deficiencies:

test procedure in accordance with national standard methods with acceptable restrictions

Remarks:

Non GLP study and limited data reported but conducted according to ÖNORM EN ISO.

Qualifier:

according to guideline

Guideline:

other: ÖNORM EN ISO6314

Version / remarks:

(06/96; 05/99)

Principles of method if other than guideline:

Deviation to the EC and OECD guidelines on acute daphnia testing: no chemical analysis was performed, exposition 24 h instead of 48 h, no details about statistical analysis, chosen concentrations do not reflect a dose response curve; the specing factor is not the same between the chosen concentrations.

GLP compliance:

no

Analytical monitoring:

no

Details on sampling:

not applicable

Vehicle:

no

Details on test solutions:

PREPARATION AND APPLICATION OF TEST SOLUTION
- Method: The test item was diluted in deionised water (Millipore ELIX 10) and the pH was adjusted with diluted NaOH and H2SO4 to 7.8 +/- 0.2.

Test organisms (species):

Daphnia magna

Details on test organisms:

TEST ORGANISM
- Common name: Daphnia mangna STRAUS
- Age at study initiation: 1-24h

Test type:

static

Water media type:

freshwater

Limit test:

no

Total exposure duration:

24 h

Post exposure observation period:

no data

Hardness:

no data

Test temperature:

20 +/- 2 °C

pH:

no data

Dissolved oxygen:

no data

Salinity:

not applicable

Nominal and measured concentrations:

Nominal concentrations:
- Preliminary test: Control, 5, 10, 15, 20, 30 and 40 g/L
- Main experiment: Control, 10, 11, 12, 13, 14, and 15 g/L

Details on test conditions:

TEST SYSTEM

- No. of organisms per vessel: not stated in the report, but according to ÖNORM EN ISO 6341 at least 20 Daphnia have to be used per concentration in the main experiment.
- No. of vessels per concentration: preliminary experiment: 2; main experiment 4
- No. of vessels per control: preliminary experiment: 2; main experiment 4


OTHER TEST CONDITIONS
- Adjustment of pH: yes, the test item was diluted in deionised water (Millipore ELIX 10) and the pH was adjusted with diluted NaOH and H2SO4 to 7.8 +/- 0.2.
- Photoperiod: the test was conducted in the dark

EFFECT PARAMETERS MEASURED (with observation intervals if applicable) :

TEST CONCENTRATIONS

- Range finding study, test concentrations: control, 0.01, 0.10 and 0.50 mg/L
- Results used to determine the conditions for the definitive study: yes

Reference substance (positive control):

no

Duration:

24 h

Dose descriptor:

EC50

Effect conc.:

>= 5 - <= 15 g/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

mobility

Details on results:

- Behavioural abnormalities: not reported
- Other biological observations: not reported
- Mortality of control: no
- Other adverse effects control: not reported
- Abnormal responses: in the main experiment slight scattered immobilisation occurred in the concentrations tested (10, 11, 12 , 13 , 14 and 15 g/L), as the range of the concentrations tested is very close this scattered immobilisation is deemed as biological variance.
- Any observations that might cause a difference between measured and nominal values: not reported
- Effect concentrations exceeding solubility of substance in test medium: no

Results with reference substance (positive control):

no data

Reported statistics and error estimates:

no data

Table 1: test results

		Concentration (g/L):
date:	test character:	0	5	10	11	12	13	14	15	20	30	40
		Immobilisation (%):
2001-11-14	preliminary	0	0	20	-	-	-	-	100	100	100	100
2001-11-20	main	0	-	70	80	40	45	65	55	-	-	-

Validity criteria fulfilled:

not specified

Conclusions:

An acute Daphnia test according to ÖNORM EN ISO 6341 was conducted. The EC50, 24 h for Succinimide was determined to be between 5-15 g/L.

Executive summary:

The 24–hr-acute toxicity of succinimide to Daphnia magna was studied under static conditions. Test species were exposed to control, and test chemical at nominal concentration of 10, 11, 12, 13, 14, and 15 g/L for 24 hr.  Immobilisation was observed at test termination. The test was conducted according to ÖNORM EN ISO 6341.

The 24-hr EC50could not be determined in the main test. As in the range finder no immobilisation was observed for an exposure concentration of 5 g/L it is assumed in the test report that the 50 % effect concentration must be between 5 to 10 g/L.

 

The study report contains only limited data and the study design deviates from OECD guideline 202 recommendations. Nevertheless, the range finder of the study shows that no immobility occurs among daphnia exposed to succinimide at 5 g/L for 24 hr. This concentration is far above the concentration relevant to classification. Results from the main test scattered without revealing a dose-response (see table 1), therefore a concrete EC50 could not be derived in the present test, but is assumed to be between 5 to 10 g/L.

 

Based on the results of this study, a classification in accordance with the classification system of CLP is not applicable.

 

Results Synopsis

 

Test Organism Age (e.g. 1^stinstar): not reported

Test Type (Flowthrough, Static, Static Renewal): Static

 

EC₅₀: 5 to 10 g/L

NOEL: 5 g/L (result from range finding test)

Endpoint(s) Effected: immobility

Description of key information

An acute Daphnia test according to ÖNORM EN ISO 6341 was conducted.

The EC50, 24 h for succinimide was determined to be between 5 to 15 g/L.

Key value for chemical safety assessment

Fresh water invertebrates

Fresh water invertebrates

Effect concentration:

5 g/L

Additional information

A study according to ÖNORM EN ISO6314 is available assessing the toxicity of succinimide towards Daphnia magna for 24 h.

In a conservative approach the lower value from the experimentally determined range (5 to 15 g/L) was chosen as EC50 value for assessment.