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Ecotoxicological information

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:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Acceptable, well-documented, peer-reviewed publication which meets basic scientific principles.

Data source

Reference
Reference Type:
publication
Title:
Unnamed
Year:
1999

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
EU Method C.2 (Acute Toxicity for Daphnia)
GLP compliance:
yes

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Details on test material:
- Molecular weight (if other than submission substance): 239.6
- Composition of test material, percentage of components: 0.9% C9 or less, 9.4% C10, 40.2% C11, 32.7% C12, 15.9% C13, 0.9% C14, 17% 2 Ph alkanes, <0.5% tetralines

Sampling and analysis

Analytical monitoring:
yes
Details on sampling:
no information

Test solutions

Vehicle:
no
Details on test solutions:
A test solutions was prepared, without use of solvent, to reach the solubility concentration (0.041 mg/1).

Test organisms

Test organisms (species):
Daphnia magna
Details on test organisms:
TEST ORGANISM
- Source: laboratory bred
- Age at study initiation (mean and range, SD): less than 24 hrs

Study design

Test type:
not specified
Water media type:
freshwater
Total exposure duration:
48 h

Test conditions

Test temperature:
20 degree C
Salinity:
0.2 g/L NaHCO3
0.224 g/l CaCl2
0.026 g/L K2SO4
Nominal and measured concentrations:
nominal: 0, 12.5%, 25%, 50%, 75%, saturated (0.041 mg/L)
Details on test conditions:
TEST SYSTEM
- No. of organisms per vessel: 5
- No. of vessels per concentration (replicates): 4
- No. of vessels per control (replicates): 4

EFFECT PARAMETERS MEASURED (with observation intervals if applicable): immobilization

Results and discussion

Effect concentrationsopen allclose all
Duration:
48 h
Dose descriptor:
NOEC
Effect conc.:
0.041 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Remarks on result:
other: > water solubility
Duration:
48 h
Dose descriptor:
EC50
Effect conc.:
> 0.041 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
mobility
Remarks on result:
other: > water solubility
Details on results:
No dose-response increase in the number of immobilized daphnids was seen. Also no significant increase in immobilization over controls was seen.

Any other information on results incl. tables

Immobilized daphnids at 48 hrs – LAB

Concentration

1

2

3

4

Control

0

1

0

0

Saturated

0

1

0

0

75%

1

0

0

1

50%

1

0

0

0

25%

0

1

0

0

12.5%

0

0

0

0

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
The 48-hr EC50 for daphnids was > 0.041 mg/L.
Executive summary:

This study determined the short-term toxicity of linear alkyl benzenes to Daphnia magna. Daphnids were exposed to concentrations of 0, 12.5%, 25%, 50%, 75%, and 100% saturated test solution for 48 hrs. At the end of this period, the daphnids were observed for mobility. Though immobilized daphnids were seen at 4 test concentrations, there was no dose-related increase in immobilization, nor was the number of immobilized daphnids significantly increased over negative controls. The 48 -hr EC50 is >0.041 mg/l, this is greater than the water solubility for the test substance.