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
Reliability:
1 (reliable without restriction)
Rationale for reliability incl. deficiencies:
other: Toxicity to aquatic algae was determined according to EU Method C.3 (Algae InhibitionTest)

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2012
Report Date:
2012

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
EU Method C.3 (Algal Inhibition test)
GLP compliance:
yes (incl. certificate)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Type:
Constituent

Sampling and analysis

Analytical monitoring:
yes
Details on sampling:
Initial Concentration of the test item : 99.8%
Sample storage conditions before analysis: in a closed vessel dark and dry at room temperature.
A stock solution containing 125.5mg/L test item in desionised water was prepared.

Test solutions

Vehicle:
yes
Details on test solutions:
From the stock solution (125.5mg/L of test item), the concentrations to be tested were prepared by diluting with desionised water.

Test organisms

Test organisms (species):
Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)
Details on test organisms:
Detail on test organism:
-Strain: CHODAT
-Family: Chlorophyceae
-Order: Chlorococcales
-Origin and culture: the culture was obtained in Oct.2011 by MBM Science-bridge GmbH (Institut für Pflanzenphysiologie of Universität Göttingen). The algae are kept as stock culture on solid agar at 8°C.
-Acclimation period: four days before the start , an aliquot of the stock culture containing a few cells was brought into pre-culture medium and incubated for 96 hours. Before usage, the culture was checked on the absence of cell aggregates. After the adjustement to a cell concentration of about 3*10^4/mL through photometric measurement and addition of algal medium, the culture was usable for the test.

Study design

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

Test conditions

Hardness:
-
Test temperature:
26°C
pH:
The pH values in the control ranged from 7.8 to 7.8.
Detail in table 9.1-b of the study report.
Dissolved oxygen:
-
Salinity:
-
Nominal and measured concentrations:
Nominal concentrations: 0.32 / 1.0 / 3.2 / 10 / 32 / 100 mg/L.
For treatments 10-100mg/L the recovery after 72 hours was in range of 94-105% of the start concentration. Details in paragraph 9.1.4 of the study report.
Details on test conditions:
TEST SYSTEM
-Test vessel: glass flasks 50mL
-Material, size, headspace, fill volume: the test vessels were filld with 45+-5mL of the mixture and were incubated open for 72 hours shaken on an orbital shaker.
-Control end cells density: before the start (initial cells density: 4526 cell nber/mL) and every 24 hours the cells numbers were determined by photometric measurment of optical density. Values in table 9.1-a of the study report.
-Replicates: six for the controls and three for each treatment.

GROWTH MEDIUM
Standard medium used
Reference substance (positive control):
yes
Remarks:
Potassium dichromate

Results and discussion

Effect concentrationsopen allclose all
Duration:
72 h
Dose descriptor:
NOEC
Effect conc.:
32 mg/L
Nominal / measured:
nominal
Conc. based on:
dissolved
Basis for effect:
growth rate
Duration:
72 h
Dose descriptor:
NOEC
Effect conc.:
32 mg/L
Nominal / measured:
nominal
Conc. based on:
dissolved
Basis for effect:
biomass
Duration:
72 h
Dose descriptor:
LOEC
Effect conc.:
100 mg/L
Nominal / measured:
nominal
Conc. based on:
dissolved
Basis for effect:
growth rate
Duration:
72 h
Dose descriptor:
LOEC
Effect conc.:
100 mg/L
Nominal / measured:
nominal
Conc. based on:
dissolved
Basis for effect:
biomass
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
dissolved
Basis for effect:
growth rate
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
73 mg/L
Nominal / measured:
estimated
Basis for effect:
biomass
Details on results:
Microscopial observation:
From 0 to 32 mg/L: normal growth.
At 100 mg/L: no cells.
Results with reference substance (positive control):
-Results with reference substance valid? YES
-EC50: the EC50s of potassium dichromate were tested in a current reference test. The values lay within the normal range of the laboratory.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
Results for 1-Aminocyclopropane-1-carbonitrile hydrochloride :
ECr50 >100mg/L
This result will not conduct to a classification "dangerous for the environment".