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:
supporting study
Study period:
2004
Reliability:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
guideline study without detailed documentation

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2005
Report Date:
2005

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
OECD Guideline 201 (Alga, Growth Inhibition Test)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Test material form:
solid: crystalline
Details on test material:
White powder
Specific details on test material used for the study:
Batch 537481-017

Test solutions

Vehicle:
yes
Details on test solutions:
To prepare the stock solution, the test item was dissolved or dispersed directly in LC reconstituted water. The obtained preparation was agitated mechanically for up to 24 hours in an attempt to completely dissolve or disperse the test item and homogenize the solution. Water reconstituted (LC) was prepared using deionized water with a conductivity less than 10 PS/cm. The final solution after autoclaving has a pH of 7.5 ± 0.3.

Test organisms

Test organisms (species):
Scenedesmus sp.
Details on test organisms:
Strain No.: CCAP 276/20
Rapidly growing unicellular species commonly used in Europe for aquatic toxicity testing and recommended in OECD and EEC guidelines.

Study design

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

Test conditions

Test temperature:
between 23,2°C and 25,4°C
pH:
between 6.91and 9,40
Conductivity:
less than 10 PS/cm
Nominal and measured concentrations:
Nominal concentration : 0, 1, 10 & 100mg/L

Results and discussion

Effect concentrationsopen allclose all
Duration:
72 h
Dose descriptor:
NOEC
Effect conc.:
ca. 10 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate
Duration:
72 h
Dose descriptor:
NOEC
Effect conc.:
ca. 10 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
biomass
Duration:
72
Dose descriptor:
EC50
Effect conc.:
ca. 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
growth rate

Applicant's summary and conclusion

Conclusions:
The highest No Observed Effect Concentration on the growth rate (NOEC) at T72h was 10 mg/L, based on growth rate and biomass (p = 0.05).

The 0-72h EC50r was > 100 mg/L.
The 0-72h EC50b was estimated as close to 100mg/L