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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:
2017
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2017

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 201 (Alga, Growth Inhibition Test)
GLP compliance:
yes (incl. certificate)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: particulate/powder

Sampling and analysis

Analytical monitoring:
yes

Test solutions

Vehicle:
yes
Remarks:
EPA medium

Test organisms

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

Study design

Test type:
not specified
Water media type:
other: EPA medium
Total exposure duration:
72 h

Test conditions

Test temperature:
22.4 - 23.0 °C
pH:
The pH values, measured at the beginning and at the end of the study, were in the range of 7.40 - 7.59 in the untreated group and 7.32 - 7.71 in the treated groups.
Reference substance (positive control):
no

Results and discussion

Effect concentrationsopen allclose all
Duration:
72 h
Dose descriptor:
EC50
Remarks:
yield value
Effect conc.:
9.27 µg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
other: yield value
Duration:
72 h
Dose descriptor:
EC50
Remarks:
growth rate
Effect conc.:
29.79 µg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Duration:
72 h
Dose descriptor:
LOEC
Effect conc.:
4.58 µg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Duration:
72 h
Dose descriptor:
NOEC
Effect conc.:
1.43 µg/L
Nominal / measured:
nominal
Conc. based on:
test mat.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
The growth inhibition test was performed in order to evaluate the effects of the test item Basic Yellow 1 on algae, after 72 hours of exposure.
Algal cultures were exposed to 1.43 - 4.58 - 14.65 - 46.88 - 150.00 μg test item/L, plus an untreated group.
The assessment of the effects was based on nominal concentrations of test item and geometric mean measured concentrations of active ingredient Thioflavine.
After 72 hours, the endpoints based on the nominal concentrations of test item Basic Yellow 1 were estimated to be the following:

EyC10 2.26 μg/L, EyC20 3.67 μg/L, EyC50 9.27 μg/L;
LOEyC 4.58 μg/L and NOEyC 1.43 μg/L;
ErC10 7.98 μg/L, ErC20 12.54 μg/L, ErC50 29.79 μg/L;
LOErC 4.58 μg/L and NOErC 1.43 μg/L.

After 72 hours, the endpoints based on the geometric mean measured concentrations of active ingredient Thioflavine were estimated to be the following:

EyC10 1.23 μg a.i./L, EyC20 2.09 a.i./L, EyC50 5.72 μg a.i./L;
LOEyC 2.44 a.i./L and NOEyC 0.94 a.i./L;
ErC10 5.81 a.i./L, ErC20 8.74 a.i./L, ErC50 19.09 μg a.i./L;
LOErC 2.44 a.i./L and NOErC 0.94 a.i./L.

At the test item concentrations 46.88 and 150.00 μg/L, cells with abnormal appearance was observed.
Executive summary:

The growth inhibition test was performed in order to evaluate the effects of the test item Basic Yellow 1 on algae, after 72 hours of exposure.

Algal cultures were exposed to 1.43 - 4.58 - 14.65 - 46.88 - 150.00 μg test item/L, plus an untreated group.

The assessment of the effects was based on nominal concentrations of test item and geometric mean measured concentrations of active ingredient Thioflavine.

After 72 hours, the endpoints based on the nominal concentrations of test item Basic Yellow 1 were estimated to be the following:

EyC10 2.26 μg/L, EyC20 3.67 μg/L, EyC50 9.27 μg/L;

LOEyC 4.58 μg/L and NOEyC 1.43 μg/L;

ErC10 7.98 μg/L, ErC20 12.54 μg/L, ErC50 29.79 μg/L;

LOErC 4.58 μg/L and NOErC 1.43 μg/L.

After 72 hours, the endpoints based on the geometric mean measured concentrations of active ingredient Thioflavine were estimated to be the following:

EyC10 1.23 μg a.i./L, EyC20 2.09 a.i./L, EyC50 5.72 μg a.i./L;

LOEyC 2.44 a.i./L and NOEyC 0.94 a.i./L;

ErC10 5.81 a.i./L, ErC20 8.74 a.i./L, ErC50 19.09 μg a.i./L;

LOErC 2.44 a.i./L and NOErC 0.94 a.i./L.

At the test item concentrations 46.88 and 150.00 μg/L, cells with abnormal appearance was observed.