Registration Dossier

Ecotoxicological information

Toxicity to aquatic algae and cyanobacteria

Administrative data

Endpoint:
toxicity to aquatic algae and cyanobacteria
Type of information:
migrated information: read-across from supporting substance (structural analogue or surrogate)
Adequacy of study:
key study
Study period:
1995
Reliability:
1 (reliable without restriction)

Data source

Reference
Reference Type:
other company data
Title:
Unnamed
Year:
1995

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 201 (Alga, Growth Inhibition Test)
Deviations:
not specified
GLP compliance:
not specified

Test material

Reference
Name:
Unnamed
Type:
Constituent

Sampling and analysis

Analytical monitoring:
yes

Test organisms

Test organisms (species):
Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum)

Study design

Test type:
not specified
Water media type:
not specified
Total exposure duration:
72 h
Remarks on exposure duration:
EL50 values determined by probit analysis. Williams test used to determine NOELs.

Results and discussion

Effect concentrationsopen allclose all
Duration:
72 h
Dose descriptor:
EL50
Effect conc.:
ca. 25 mg/L
Nominal / measured:
nominal
Conc. based on:
not specified
Basis for effect:
biomass
Remarks on result:
other: 95% confidence interval of 21 - 30 mg/l
Duration:
72 h
Dose descriptor:
EL50
Effect conc.:
ca. 78 mg/L
Nominal / measured:
nominal
Conc. based on:
not specified
Basis for effect:
growth rate
Remarks on result:
other: 95% confidence interval of 64 - 96 mg/l

Any other information on results incl. tables

Based on nominal loading rates:

72-hr EL50 (biomass) = 25 mg/l 95% confidence interval of 21 - 30 mg/l

72-hr EL50 (growth rate) = 78 mg/l 95% confidence interval of 64 - 96 mg/l

72-hr NOEL (biomass) = 3 mg/l

72-hr NOEL (growth rate) = 10 mg/l.

Nominal 72h 72 h Mean Cell conc.
Conc.(mg/l) % Inhibition (million cells/ml)
Control n/a 0.14
1.0 -21 0.17
3.0 -36 0.19
10 29 0.10
30 61 0.055
100 91 0.013
300 94 0.0087
1000 95 0.0074

n/a - Not applicable

The pH increased by more than one unit (1.1 units) during the test as a result of good culture growth and could not be avoided. Temperature range in the incubator was outside the preferred range of 21 - 25 °C. The out-of-range readings were recorded in the first four hours of the test probably due to temperature fluctuations associated with opening and closing the incubator. These deviations were not sufficient to invalidate the study. Analytical method used was gas chromatography-mass spectrometry. Mean reduction in the concentration of dissolved hydrocarbons during the test was 14% (range 0 - 40%).

Applicant's summary and conclusion