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: Guideline study and GLP

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2009
Report Date:
2009

Materials and methods

Test guidelineopen allclose all
Qualifier:
according to
Guideline:
OECD Guideline 201 (Alga, Growth Inhibition Test)
Deviations:
yes
Remarks:
, The following deviation from the study plan was documented: -The temperature in the main study was higher than stated in the guidelines. As algal growth in the controls was normal, this deviation was stated as uncritical. The deviation was signed and a
Qualifier:
according to
Guideline:
EU Method C.3 (Algal Inhibition test)
Deviations:
yes
Remarks:
, The composition of stock solution ll is taken from OECD Guideline 201. As in EU-Method C.3, a different composition (80 mg FeCl3*6HzO/L) is stated, this is stated as a deviation from the EU Method.
GLP compliance:
yes (incl. certificate)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Details on test material:
Name: Kn 172
Batch no.: Kn-Gi 9328-182
Appearance: white powder
Molecular formula: C13H18N4 x 3HCl
Molecular weight: 339.69 g/mol
Purity: NMR: 96.2%, 0.8% EtOH, 1.4% water
Homogeneity: not stated
Vapour pressure: not stated
Stability: unknown
Solubility H2O: > 1 g/L; EtOH; acetone; CH3CN; DMSO: unknown
Production date: not stated
Expiry date: 10. Jun. 2013
Storage: fridge 2 - 8° C, keep away from light and humidity, keep under Ar!

Sampling and analysis

Analytical monitoring:
yes

Test solutions

Vehicle:
no

Test organisms

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

Study design

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

Results and discussion

Effect concentrationsopen allclose all
Duration:
72 h
Dose descriptor:
other: ErC50
Effect conc.:
8.3 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Remarks on result:
other: 5.6 - 14.9 mg/L
Duration:
72 h
Dose descriptor:
other: EbC50
Effect conc.:
2.3 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
other: AUC (Area Under Curve according to EU Method C.3)
Remarks on result:
other: 1.4 - 3.4 mg/L
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
2.4 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Duration:
72 h
Dose descriptor:
NOEC
Effect conc.:
2.2 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Duration:
72 h
Dose descriptor:
LOEC
Effect conc.:
4.6 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
Kn 172 is considered toxic to algae (Desmodesmus subspicatus)
Executive summary:

Two experiments were performed.

As the test item wasn't stable under test conditions and in the samples which were taken

for analytical determinations, the results of the analytical determinations in the first experiment

were considered as insufficient. Therefore, a second experiment was performed.

The study was performed using five concentrations ranging from 1.0 to 22 mg/L. The

treatments were used to incubate the unicellular freshwater green algae Desmodesmus

subspicatus for a period of 72 hours. The cell concentration of each replicate was determined

microscopically with counting chamber every 24 hours. From the measured cell

numbers, the growth rate µ, the area under the growth curve (AUC) and the Yield were

determined.

At the start, after 2, 24 and 48 hours, the content of the test item in the test solutions was

determined using HPLC. All samples are measured separately and directly after sampling

and not by using an auto sampler.

The measured concentration at the beginning of the test was between 82 % and 104 % of

the nominal concentration. The recovery after 2 hours was in a range of 56 and 69 % of

the start concentration. After 24 hours, no test item was detectable. Therefore, calculation

of the mean of the measured concentration at the start and the end of the test wasn't feasible.

lt is believed that the toxic effects of the test item took part within the first 24 hours.

The determination of the results was based on the nominal concentrations.

The EC50s of potassium dichromate were tested in a current reference test. The values

lay within the normal range of the laboratory.

The following results for the test item Kn 172 were determined:

 Endpoint  NOEC  LOEC  EC50
 Growth Rate  2.2 mg/L  4.6 mg/L  8.3 mg/L
 AUC  1.0 mg/L  2.2 mg/L  2.3 mg/L
 Yield  2.2 mg/L  4.6 mg/L  2.4 mg/L