Registration Dossier

Ecotoxicological information

Toxicity to aquatic algae and cyanobacteria

Administrative data

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
experimental study
Adequacy of study:
key study
Study period:
06.06.2000-09.06.2000
Reliability:
1 (reliable without restriction)

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2000
Report Date:
2000

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
ISO 10253 (Water quality - Marine Algal Growth Inhibition Test with Skeletonema costatum and Phaeodactylum tricornutum)
GLP compliance:
no

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: crystalline

Sampling and analysis

Analytical monitoring:
yes

Test solutions

Details on test solutions:
Stock solution at 200 mg/l

Test organisms

Test organisms (species):
Skeletonema costatum
Details on test organisms:
TEST ORGANISM
- Strain: Skeletonema costatum (NIVA BAC 1)
- Source (laboratory, culture collection): Kept in culture at DHI.

Study design

Water media type:
saltwater
Limit test:
no
Total exposure duration:
72 h

Test conditions

Test temperature:
19ºC
pH:
8.0
Salinity:
28 ‰
Details on test conditions:
TEST SYSTEM
- Test vessel: Bottles
- Salinity (for marine algae): 28 ‰

TEST CONCENTRATIONS
- Range finding study: A screening study with the following test concentrations: 0, 0.1, 1, 10, 100, 1000 mg/l showed the EC50 was between 1.0-10.0 mg/l
Therefore the definitive test concentrations was: 0, 0.5, 1, 2, 5, 10, 20 & 50 mg/l.
Reference substance (positive control):
yes
Remarks:
3,5-dichlorphenyl

Results and discussion

Effect concentrationsopen allclose all
Duration:
72 h
Dose descriptor:
NOEC
Effect conc.:
0.5 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
biomass
Duration:
72 h
Dose descriptor:
LOEC
Effect conc.:
1 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
biomass
Duration:
72 h
Dose descriptor:
EC10
Effect conc.:
0.75 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
biomass
Remarks on result:
other: 0.37-0.99
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
1.95 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
biomass
Remarks on result:
other: 1.62-2.68
Results with reference substance (positive control):
- Results with reference substance valid? Yes
- EC50: 1.37 mg/l
The sensitivity of the algae was tested with 3,5 -dichlorphenol and calculation showed an EC50(72h) 1.37 mg/l. This is in between the normal findings (EC50: 1.6±0.3 mg/l). The sensitivity of thealgae is assessed to be normal.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Remarks:
Cell density increased by a factor of more than 16 during test, results for reference substance within acceptable range, 1.6±0.3 mg/l, variation of pH in controls < 1.0
Conclusions:
The substance has a EC50(72 h) of 1.95 mg/L for Skelotonema costatum.