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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:
From October 25th, 2002 to November 5th, 2002
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2002
Report date:
2002

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to guideline
Guideline:
OECD Guideline 201 (Alga, Growth Inhibition Test)
Version / remarks:
1984
Qualifier:
according to guideline
Guideline:
EU Method C.3 (Algal Inhibition test)
Version / remarks:
1992
GLP compliance:
yes (incl. QA statement)

Test material

Constituent 1
Reference substance name:
Yellow 6314-PPT
IUPAC Name:
Yellow 6314-PPT
Test material form:
solid

Sampling and analysis

Analytical monitoring:
yes

Test solutions

Vehicle:
no
Details on test solutions:
Due to the low water solubility of the test item, a supersaturated dispersion of the test item with a loading rate of nominal 100 mg/l was continuously stirred at room temperature in the dark over 3 hours. Then the dispersion was filtered. The undiluted filtrate with the maximum concentration of dissolved test item was used as the only test medium. Additionally, a control was tested in parallel.

Test organisms

Test organisms (species):
Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Study design

Test type:
static
Water media type:
freshwater
Limit test:
yes
Total exposure duration:
72 h

Test conditions

Hardness:
24 mg CaCO3 / l
Test temperature:
22-23 °C
pH:
7.9-8.5 undiluted filtrate
7.9-8.4 control
Nominal and measured concentrations:
Nominal 100 mg/l as loading rate
Details on test conditions:
Cell density at t = 0 h: 10^4 cells/ml
Reference substance (positive control):
no

Results and discussion

Effect concentrationsopen allclose all
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
biomass
Duration:
72 h
Dose descriptor:
NOEC
Effect conc.:
100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Duration:
72 h
Dose descriptor:
NOEC
Effect conc.:
100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
biomass
Details on results:
The test item had clearly no inhibitory effect on the growth of Scenedesmus subspicatus during the exposure period of 72 hours at a loading rate of 100 mg/l (mean measured test item concentration of 1.8 μg/l). This test concentration was therefore determined as the 72-hour NOEC (highest concentration tested without toxic effects after a test period of 72 hours). The NOEC might even be higher but concentrations in excess of the loading rate of 100 mg/l have not been tested, due to the low water solubility of the test item in the used test water.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
The test item had no toxic effect on the algae up to its solubility limit in test water.