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 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
Details on test material:
TEST ITEM: Gro 266
Batch number: Gro-RN-9963-191
CAS-No.: 223398-24-1
Content: > 99 weight %
Chemical name: 4-Acetyl-1-methylpyridinium-p-toluolsulfonate
Appearance: White-beige powder
Sum formula: C8H10NO x C7H7SO3
Molecular weight: 307.37 g/mol
Water solubility: Approx. 500 g/L
pH value: Approx. 3.8 (200 g/L)

Expiry date: 2014-04-01
Recommended storage: Frigid, dark
Storage at test facility: 6 ± 2 °C, protected from moisture and light
Retention of test item: At least 1 g has been retained.
ldentification parameter at test facility: Name, batch number, state, consistency and colour

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:
yes
Total exposure duration:
72 h

Results and discussion

Effect concentrationsopen allclose all
Duration:
72 h
Dose descriptor:
NOEC
Effect conc.:
100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Duration:
72 h
Dose descriptor:
LOEC
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Duration:
72 h
Dose descriptor:
EC10
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Duration:
72 h
Dose descriptor:
EC20
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate

Any other information on results incl. tables

The toxicity of Gro 266 (batch number Gro-RN-9963-191) to the unicellular freshwater green

alga Desmodesmus subspicatus was determined according to the principles of OECD 201 at

Dr.U.Noack-Laboratorien in 31157 Sarstedt, Germany from September 15 to 18,2009. The

aim of the study was to assess the effects on growth rate and yield over a period of 72 h.

The study was conducted under static conditions with an initial cell density of approximately

2 - 5 x 10³ cells/mL. Based on a preliminary range finding test, a limit test with a nominal

concentration level of 100 mg/L was carried out. Six replicates were tested for the limit

concentration and control. Environmental conditions were determined to be within the

acceptable limits.

The concentrations of Gro 266 were analysed at test start and test end via HPLC-DAD analysis.

The measured recovery rates of the test item (with and without algae) at test start and end were

101 - 102 olo and 99 - 100 % of the nominal value, respectively. All effect values are given

based on the nominal concentration of the test item.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
ln this study Gro 266 was found not to inhibit the freshwater green alga Desmodesmus
subspicatus after 72 h at 100 mg/L. All effect levels are given based on nominal concentrations of Gro 266.