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:
guideline study

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2018
Report Date:
2018

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 201 (Alga, Growth Inhibition Test)
Deviations:
no
GLP compliance:
yes (incl. certificate)

Test material

Reference
Name:
Unnamed
Type:
Constituent

Sampling and analysis

Analytical monitoring:
yes
Details on sampling:
Samples from all controls and treatment groups were taken at the test start and at the test end.

Test solutions

Vehicle:
no
Details on test solutions:
The definitive test was performed using the test item loading rate of 60 mg/L, and 2.5-fold, 6.25-fold, 15.63-fold, 39.06-fold diluted filtrates of the loading rate of 60 mg/L plus the filtrate of the control.
Appropriate amount of the test item was weighed in a glass crystallizer, quantitatively transferred into a glass vessel and filled up to full volume (without headspace) with the AAP medium. The glass vessel was tightly closed with a glass cap.
The loading rate of 60 mg/L was visually heterogeneous with visible undissolved particles. The test item loading rate and the control (the AAP medium, 35 L) were mechanically shaken for 24 h (room temperature, 50 revolutions per minute). After 24 h of mechanical shaking, the loading rate (heterogeneous) and the control were stored at room temperature for a settling phase (no shaking). After 24 h of settling phase, the loading rate was still visually heterogeneous. Therefore, the loading rate and the control were filtered through a conditioned nitrocellulose membrane filter (0.22 µm, GSTF, Millipore), [SOP/W/37]. This is a WAF-approach followed by filtering, which results in a water soluble fraction. Each filtrate was visually homogeneous and transparent. The filtrate of the loading rate of 60 mg/L was sequentially diluted with filtrate of the control to prepare the lower test item concentrations.
All exposure levels and the control were inoculated with the algal pre-culture to obtain the initial algal density of 0.01 x 106 cells/mL.

Test organisms

Test organisms (species):
Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum)
Details on test organisms:
TEST ORGANISM
- Common name: Green algae
- Source (laboratory, culture collection): Unicellular freshwater green algae Pseudokirchneriella subcapitata (Reinsch) Korshikov (syn. Selenastrum capricornutum Prinz, Raphidocelis subcapitata Korshikov), specification SAG 61.81, cultured in the Institute of Industrial Organic Chemistry, Branch Pszczyna, Department of Ecotoxicology, Laboratory of Aquatic Toxicology, stock from the Culture Collection of Algae at Göttingen University, Germany.


Study design

Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
72 h

Test conditions

Test temperature:
21.7 - 22.1 °C
pH:
7.43 - 8.81
Conductivity:
139.6 µS/cm
Nominal and measured concentrations:
Nominal: 0, filtrate of the test item loading rate of 60 mg/L and 2.5-fold, 6.25-fold, 15.63-fold,and 39.06-fold diluted filtrates of the loading rate of 60 mg/L.
Measured: < 0.18 (control); 0.73, 1.69, 4.05, 9.46, 24.54 mg/L
Analytical measured concentrations were within 89.6 – 97.5% of the initial concentrations in all treatment groups.
Details on test conditions:
TEST SYSTEM
- Test vessel: Erlenmeyer flasks
- Type (delete if not applicable): closed
- Material, size, headspace, fill volume: 250 ml
- Aeration: no
- Initial cells density: 1E+04
- No. of vessels per concentration (replicates): 3
- No. of vessels per control (replicates): 6

GROWTH MEDIUM
- Standard medium used: yes

TEST MEDIUM / WATER PARAMETERS
- Source/preparation of dilution water: according to OECD 201
- Intervals of water quality measurement: daily

OTHER TEST CONDITIONS
- Sterile test conditions: no
- Adjustment of pH: no
- Photoperiod: cointinuous illumination
- Light intensity and quality: 7000 – 7494 lux


EFFECT PARAMETERS MEASURED (with observation intervals if applicable) : cell density after 24, 48 and 72 h
- Determination of cell concentrations: [counting chamber; electronic particle counter; fluorimeter; spectrophotometer; colorimeter]Countng, indiecte spectophotometric measurements at 670 nm.



Reference substance (positive control):
yes
Remarks:
3,5-dichlorophenol

Results and discussion

Effect concentrationsopen allclose all
Key result
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
5.11 mg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
test mat.
Basis for effect:
growth rate
Key result
Duration:
72 h
Dose descriptor:
NOEC
Effect conc.:
1.69 mg/L
Nominal / measured:
meas. (geom. mean)
Conc. based on:
test mat.
Basis for effect:
growth rate
Results with reference substance (positive control):
72 h ErC50: 3.23 mg/L
Reported statistics and error estimates:
Probit method calculations and analysis by Shapiro-Wilk’s Test on Normal Distribution, Levene’s Test on Variance Homogeneity (with Residuals), Williams Multiple Sequential t-test Procedure.

Applicant's summary and conclusion