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
Study period:
March - July 2013
Reliability:
1 (reliable without restriction)
Qualifier:
according to
Guideline:
OECD Guideline 202 (Daphnia sp. Acute Immobilisation Test)
Deviations:
no
Qualifier:
equivalent or similar to
Guideline:
EU Method C.2 (Acute Toxicity for Daphnia)
GLP compliance:
yes
Specific details on test material used for the study:
Identifier: EXP1200078
Appearance: Very dark brown (almost black) viscous liquid
Batch: E00275-350
Sample Expiration Date: end-2013
Purity:100%
Analytical monitoring:
no
Vehicle:
no
Details on test solutions:
Test solutions were prepared individually by adding a calculated amount of test substance into tared glass beaker and sonicating for 10 to 15 minutes with a portion of the pre-measured 4 L of dilution water to be used for the final solution volume. Following sonication, the contents of the beakers were emptied and mixed into the aspirator bottle containing the remaining 4 L of dilution water using a Teflon-lined stir bar for 48 hours at nominal WAF loading rates of 6.3, 13, 25, 50 and 100 mg/L. Care was taken to maintain the vortex depth for each WAF at approximately 30% of the test solution height. Following the mixing period, the WAF solution was allowed to settle for approximately 1 hour and the test solution was decanted from mid-depth and filtered with a 20-25 µm paper filter. Finally, 250 mL of test solution was placed in each of two replicate test chambers per treatment group. The negative control solution was dilution water only.
Test organisms (species):
Daphnia magna
Details on test organisms:
At test initiation, the juvenile daphnids were collected from the cultures and indiscriminately transferred one or two at a time to transfer chambers until each chamber contained 10 daphnids. Each group of daphnids then was transferred to an indiscriminately assigned test chamber to initiate the test.
Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
48 h
Post exposure observation period:
24 and 48 hours
Hardness:
approximately 136 mg/L as CaCO3
Test temperature:
19.6 - 20.5C
pH:
8.2 - 8.5
Dissolved oxygen:
7.5 - 8.3 mg O2/L
Salinity:
no data
Nominal and measured concentrations:
Nominal WAF loading rates selected for use in this study were 6.3, 13, 25, 50 and 100 mg/L.
Details on test conditions:
Test chambers were 250 mL glass beakers filled with approximately 220 mL of test water. The depth of the test water in a representative chamber was 6.2 cm. The chambers were indiscriminately positioned by treatment group in a temperature-controlled environmental chamber to maintain the target water temperature throughout the test period. All test chambers were labeled with the project number, test level and replicate designation.

Each chamber contained 10 daphnids. Each group of daphnids then was transferred to an indiscriminately assigned test chamber to initiate the test.

The water used for culturing and testing was fresh water obtained from a well approximately 40 meters deep located on the Wildlife International site. The well water was passed through a sand filter to remove particles greater than approximately 25 ¿m, and pumped into a 37,800 L storage tank where the water was aerated with spray nozzles. Prior to use, the water was filtered to 0.45 ¿m to remove fine particles and was passed through an ultraviolet (UV) sterilizer.

Dilution water was monitored for pH, dissolved oxygen, hardness, inorganics and pesticides.

Reference substance (positive control):
no
Key result
Duration:
24 h
Dose descriptor:
EC50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Key result
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Details on results:
Daphnia in the negative control groups appeared normal throughout the test. All daphnids in the 6.3, 13, 25, 50 and 100 mg/L treatment group also appeared either normal or were observed trapped on the surface but then appeared normal after gentle submersion throughout the test, with no immobility or overt signs of toxicity observed.

Percent immobility at test termination in the 6.3, 13, 25, 50 and 100 mg/L treatment groups was 0%, for all of the treatment groups. EL50 values at 24 and 48 hours were determined from the immobility data and
Reported statistics and error estimates:
The absence of immobile daphnids in any of the EXP1200078 treatment groups during the test precluded the statistical calculation of EL50 values at 24 and 48 hours. Therefore, the EL50 values were estimated to be greater than the highest level tested. The no-immobility level and the no observed-effect level (NOEL) were determined by visual interpretation of the immobility and observation data.
Validity criteria fulfilled:
yes
Executive summary:

The cladoceran, Daphnia magna, was exposed for 48 hours under static conditions to five nominal WAF loading rates of EXP1200078 ranging from 6.3 to 100 mg/L. The 48 hour EL50 value was >100 mg/L, the highest concentration tested. The 48 hour no-immobility concentration and the NOEL were both =100 mg/L.

Description of key information

The cladoceran, Daphnia magna, was exposed for 48 hours under static conditions to five nominal WAF loading rates of EXP1200078 ranging from 6.3 to 100 mg/L. The 48 hour EL50 value was >100 mg/L, the highest concentration tested. The 48 hour no-immobility concentration and the NOEL were both =100 mg/L.

Key value for chemical safety assessment

EC50/LC50 for freshwater invertebrates:
100 mg/L

Additional information