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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:
March 2-6th, 1987
Reliability:
1 (reliable without restriction)

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1987
Report date:
1987

Materials and methods

Test guideline
Qualifier:
according to guideline
Guideline:
other: The toxicity test was performed according to the SBI protocol "96-hour toxicity test with the Freshwater Alga, Selenastrum capriconutum", february 1987.Culture techniques and test procedures were based on the Algal Acute Toxicity Test (US EPA, 1985a) and
Deviations:
not specified
GLP compliance:
yes

Test material

Constituent 1
Chemical structure
Reference substance name:
-
EC Number:
419-690-3
EC Name:
-
Cas Number:
88020-55-7
Molecular formula:
[(C12H25)3NH]4Mo8O26
IUPAC Name:
tridodecylamine hydrate molybdenum

Sampling and analysis

Analytical monitoring:
not specified

Test solutions

Vehicle:
not specified
Details on test solutions:
A clear, green superstock solution of 100mg/L was prepared by adding 5,01 g of NORCAT M to a sterile 50mL volumetric flask and diluting to volume with acetone. The superstock solution was ultraconicated for approximately 5 minutes to ensure that all of the test material had gone into solution. 100 microlitres of the superstock solution were added to a sterile 1L volumetric flask and diluted to volume with MDL solution to prepare a 10mg/L stock solution. Test solutions were prepared by adding appropriate volumes of stock solution to sterile 500mL volumetric flask, and diluting to volume with MDL medium. 2 control flasks containing MDL medium but no test material were prepared. One flask contained the greatest amounts of solvant used (0.1mL/L) and was labelled the Solvant Control. Test flasks labelled Control and solvant control were maintained under the same conditions as the test flasks containing NORCAT M.

Test organisms

Test organisms (species):
Raphidocelis subcapitata (previous names: Pseudokirchneriella subcapitata, Selenastrum capricornutum)
Details on test organisms:
TEST ORGANISM
- Common name: Selenastrum capricornutum
- Strain: Freshwater green alga
- Source (laboratory, culture collection): Carolina Biological Supply Company Burlington, North Carolina,
- Age of inoculum (at test initiation): 7-day-old inoculum
- Method of cultivation:
Medium prepared with deionized water.

ACCLIMATION
- Acclimation period:
- Culturing media and conditions (same as test or not):
- Any deformed or abnormal cells observed:

Study design

Test type:
not specified
Water media type:
freshwater
Limit test:
yes
Total exposure duration:
96 h

Test conditions

Hardness:
Water hardness : 160-180mg/L
Test temperature:
23-24°c
Details on test conditions:
- Constant illumination (about 5 000lux)
- shaking at 100rpm

Results and discussion

Effect concentrationsopen allclose all
Duration:
96 h
Dose descriptor:
EC50
Effect conc.:
1.1 mg/L
Remarks on result:
other: 95% confidence interval : 0.024 - 120mg/L
Duration:
96 h
Dose descriptor:
EC50
Effect conc.:
0.14 mg/L
Duration:
96 h
Dose descriptor:
IC50
Effect conc.:
110 mg/L
Duration:
96 h
Dose descriptor:
NOEC
Effect conc.:
0.015 mg/L

Any other information on results incl. tables

Measured test concentrations : (based on mean of 0- and 96 -hour analyses) :

0.0054       0.015       0.023       0.047       0.092       0.17       0.30       0.87       1.70       mg/L

Decrease (%) of the concentration of test substance, during the test period :

The test of concentration remains relatively constant between 0 and 96 hours.

Applicant's summary and conclusion

Conclusions:
96-hour EC50 : 1.1mg/L, based on cell density (relative to the control)
NOEC : 0.015mg/L