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: The study was conducted according to the O.E.C.D. test guideline 201 with GLP compliance.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
2011
Report Date:
2011

Materials and methods

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

Test material

Reference
Name:
Unnamed
Type:
Constituent
Type:
Constituent
Details on test material:
As per IUCLID Sections 1.1. 1.2. and 4.1.

Sampling and analysis

Analytical monitoring:
no

Test solutions

Details on test solutions:
The appropriate amount of test substance was added to 250 ml glass flasks to yield a concentration of approximately 100 mg/L when mixed with alagal stock culture growth medium for one hour.

Test organisms

Test organisms (species):
Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum)
Details on test organisms:
Algal cultures were grown in Algal stock culture medium (Woods Hole) with up to 300 mg EDTA/L by Stillmeadow. The cultures were maintained at 24 =/- 2 degrees C with constant aeration and continuos lighting of 400 +/- 40 ft.c.

Study design

Test type:
static
Water media type:
freshwater
Limit test:
yes
Total exposure duration:
72 h
Post exposure observation period:
None

Test conditions

Hardness:
No data
Test temperature:
23 C
pH:
7.8 mean
Dissolved oxygen:
No data
Salinity:
No data
Nominal and measured concentrations:
100 mg/L nominal (Limit Test)
Details on test conditions:
Cultures were prepared to contain approximately 50,000 algal cells/ml. There were six flasks for treated cultures, five flasks for the untreated control and three flasks for the positive control 10 mg/ml zinc chloride. All flasks were set on a shaker table for constant shaking at approximately 100 cycles/minute. At interval of 24, 48 and 72 hours following the intiation of treatment all cultures were sampled to assess cell density with a hemacytometer.
Reference substance (positive control):
yes
Remarks:
Zinc chloride at 10 mg/L

Results and discussion

Effect concentrations
Duration:
72 h
Dose descriptor:
EC50
Effect conc.:
> 100 mg/L
Nominal / measured:
nominal
Conc. based on:
test mat.
Basis for effect:
cell number
Details on results:
The mean relative percent survial of the 100 mg/L Limit Dose after 72 hour of treatment was 108% with terminal pH of 7.6. Control culture mean pH was 7.7.
Results with reference substance (positive control):
No algal cell growth was observed in the positive control cultures.

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Remarks:
Mean control cell density increased by a factor > 16.
Conclusions:
The EC50 and NOEC for the test substance to green algae is > 100 mg/L.
Executive summary:

The EC50 and NOEC for the test substance, 4,4'-Isopropylidenedicyclohexanol, oligomeric reaction products with 1-chloro-2,3-epoxypropane, to green algae in an O.E.C.D. test guideline 201 study is > 100 mg/L.