Registration Dossier

Ecotoxicological information

Short-term toxicity to aquatic invertebrates

Currently viewing:

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:
2002
Report Date:
2002

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
EU Method C.2 (Acute Toxicity for Daphnia)
Qualifier:
according to
Guideline:
OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)
GLP compliance:
yes (incl. certificate)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Specific details on test material used for the study:
Identification: Nitrile Iso C 11
Description: Colourless liquid
Batch: 004925
Test substance storage: At room temperatre in the dark
Expiry date: 08 march 2003

Sampling and analysis

Details on sampling:
The sampling scheme during the final study was as follows:
Frequency: At the start and the end of the exposure period samples were taken from all test concentrations.
Volume: 10 ml from the approximate centre of the test vessels
Storage: Not applicable, samples were analysed on the dat of sampling

Test solutions

Vehicle:
yes
Remarks:
acetone

Test organisms

Test organisms (species):
Daphnia magna
Details on test organisms:
Reason for selection: This system has been selected as an internationally accepted species
Validity of batch: Frequent inspection of the cultures with respect to number of young, appearance of young and paternal daphnia and global feeding behaviour.
Characteristics: For the test selection of young daphnia with an age of < 24 hours
Start of each batch: With new-born animals i.e. less than 3 days old, by placing about 250 of them into 10 litres of medium in an all-glass cultre vessel.
Maximum age of the cultures: 4 weeks
Renewal of the cultures: After 7 days of cultivation half of the medium twice a week
Temperature of medium: 18 - 22 °C, constant within +/- 1 °C
Feeding: Daily, a suspension of fresh water algae
Medium: M7, as prescribed by Dr. Elendt-Schneider

Study design

Test type:
flow-through
Water media type:
other: tap water
Total exposure duration:
48 h

Test conditions

Test temperature:
Measured daily in all vessels, beginning at the start of the test. The test temperature of the test medium measured once a day in the blank-control group ranged from 20.4 to 20.5 °C.
pH:
Measured at the beginning, after 24 hours and at the end of the test, for all concentration and the control.
pH: 7.7-7.9
Dissolved oxygen:
Measured at the beginning, after 24 hours and at the end of the test, for all concentration and the control
O2: 8.9-9.4
Nominal and measured concentrations:
Nominal: 0.56, 1.0, 1.8, 3.2 and 5.6 mg/L
Measured: The results of analysis of the samples taken during the final study showed that the measured concentrations during the 48 hour test period were generally maintained stable at 100 +/- 20% of the target concentratins. Hence, parameters will be based on the target concentrations.
Details on test conditions:
Controls: Tap-water without test substance (blank-control) and tap-water containing 0.1 ml acetone per litre (treatment-control)
Reference substance (positive control):
yes
Remarks:
potassium dichromate

Results and discussion

Effect concentrations
Duration:
48 d
Dose descriptor:
EC50
Effect conc.:
1.2 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Remarks on result:
other: 95% confidence interval between 1.1 and 1.4 mg/L
Details on results:
The results of analysis of the samples taken during the final study showed that the measured concentrations during the 48 hour test period were generally maintained stable at 100 +/- 20% of the target concentratins. Hence, parameters will be based on the target concentrations.

Any other information on results incl. tables

Acceptability of the test:

1. In the controls, less than 10% of the Daphnia had been immobilised or trapped at the surface of the water

2. The analytical program provided clear evidence that the actual concentrations had been maintained between 80 and 120 % of the average exposure conentrations.

3. Further, all test conditions (pH, dissolved oxygen and temperature) remained within the ranges prescribed by the protocol.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
Under the conditions of the present study Nitrole Iso C 11 did not induce acute immoblisation of Daphnia magna at or below 0.56 mg/l under flow-through test conditions (NOEC).
The 48h-EC50 for Daphnia exposed to Nitrole Iso C11 was 1.2 mg/l with a 95% confidence interval between 1.1 and 1.4 mg/l.