Registration Dossier

Ecotoxicological information

Short-term toxicity to aquatic invertebrates

Currently viewing:

Administrative data

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:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
study well documented, meets generally accepted scientific principles, acceptable for assessment
Qualifier:
according to
Guideline:
other: The procedures used in the test were based on protocols in "Methods for acute toxicity tests with fish, macroinvertebrates, and amphibians" (U.S. EPA 1975).
GLP compliance:
no
Specific details on test material used for the study:
All chemicals tested were purchased from commercial chemical suppliers and had a minimum purity of 80%. The chemicals were tested on an active ingredient basis and concentrations are reported as milligrams (mg) of test material per litre of diluent water.
Analytical monitoring:
no
Vehicle:
not specified
Test organisms (species):
Daphnia magna
Details on test organisms:
TEST ORGANISM
- Common name: Daphnia magna
- Source: Daphnia magna (<24 hours old) were from laboratory stocks cultured at EG&G Bionomics.
- Feeding during test Not stated.
- Food type: Not stated.

ACCLIMATION
- Acclimation period: Not stated.


Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
48 h
Hardness:
173mg/L as CaCO3 (mean value test water)
Test temperature:
22 ± 1°C
pH:
7.4 to 9.4 (test water)
Dissolved oxygen:
6.5 to 9.1 mg/L (test water)
Details on test conditions:
TEST SYSTEM
- Test vessel: 250 mL beaker
- Fill volume: 150 mL of control/test solution.
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): triplicate
- No. of vessels per control (replicates): Not stated
- No. of vessels per vehicle control (replicates):Not stated (Use of a vehicle for the test substance was not confirmed in the publication)

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: Water used to culture the organisms was deionised reconstituted well water having a total hardness of 72 ± 6 mg/L as CaCO3 and a pH of 7.0 ± 0.2. Subsequently culture water was reconstituted according to U.S. EPA (1975) to a total hardness of 173 ±13 mg/L as CaCO3 and a pH of 8.0 ± 0.2, to improve conditions for test organisms.

OTHER TEST CONDITIONS
- Adjustment of pH: Not stated
- Photoperiod: Not stated
- Light intensity: Not stated
Key result
Duration:
24 h
Dose descriptor:
EC50
Effect conc.:
56 mg/L
Nominal / measured:
nominal
Conc. based on:
act. ingr.
Basis for effect:
mortality
Key result
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
46 mg/L
Nominal / measured:
nominal
Conc. based on:
act. ingr.
Basis for effect:
mortality
Key result
Duration:
48 h
Dose descriptor:
NOEC
Effect conc.:
< 7.8 mg/L
Nominal / measured:
nominal
Conc. based on:
act. ingr.
Basis for effect:
mortality

Mortality among water flea control populations never exceeded 10% in any test (study was part of a series of tests on a number of compounds).

Validity criteria fulfilled:
not specified
Conclusions:
The 48-hour EC50 of the test substance to Daphnia magna was 46 mg/L based on mortality. The 48-hour NOEC was <7.8 mg/L.
Executive summary:

Introduction

The toxicity of the test substance to Daphnia magna was investigated using procedures presented in: "Methods for acute toxicity tests with fish, macroinvertebrates, and amphibians" (U.S. EPA 1975).

Method

Five daphnids were randomly placed in 250 mL beakers containing 150 mL of test solution at up to five to eight nominal concentrations. Exposures were undertaken in triplicate. A negative control consisting of the same dilution water, test conditions, and test organisms, but containing no test substance was maintained concurrently. During the tests, the dissolved oxygen concentration, pH and temperature of test solutions were measured at the initiation and termination of the toxicity tests in the high, middle and low test concentrations and controls.

Observations of test populations were made at 24 and 48 hours of exposure and any mortalities were recorded.

Results and Conclusion

The 48-hour EC50 of the test substance to Daphnia magna was 46 mg/L based on mortality. The 48-hour NOEC was <7.8 mg/L.

Description of key information

Toxicity of the test substance to Daphnia magna.

Key value for chemical safety assessment

EC50/LC50 for freshwater invertebrates:
46 mg/L

Additional information