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:
2 (reliable with restrictions)
Rationale for reliability incl. deficiencies:
other: Study was conducted at only one dose point and lacked experimental detail.

Data source

Reference
Reference Type:
study report
Title:
Unnamed
Year:
1992
Report Date:
1992

Materials and methods

Test guideline
Qualifier:
according to
Guideline:
EPA OTS 797.1050 (Algal Toxicity, Tiers I and II)
Deviations:
no
GLP compliance:
yes (incl. certificate)

Test material

Reference
Name:
Unnamed
Type:
Constituent
Details on test material:
As per IUCLID5 Sections 1.1. - 1.4.

Sampling and analysis

Analytical monitoring:
yes
Details on sampling:
Samples taken at 0 and 96 hr.

Test solutions

Vehicle:
no
Details on test solutions:
The test solution was prepared in algal media such that the final nominal concentration was 18 mg/L. The stock solution was stirred for approximately one hour, and allowed to equilibrate for 96 hours before use.

Test organisms

Test organisms (species):
Pseudokirchneriella subcapitata (previous names: Raphidocelis subcapitata, Selenastrum capricornutum)
Details on test organisms:
Selenastrum caprkornutum was used for the test. The parent stock of algae used in the testing was obtained from the Culture Collection of Algae, University of Texas, Austin, Texas.

Study design

Test type:
static
Water media type:
freshwater
Limit test:
no
Total exposure duration:
96 h
Post exposure observation period:
None

Test conditions

Hardness:
No data
Test temperature:
No data
pH:
No data
Dissolved oxygen:
No data
Salinity:
No data
Nominal and measured concentrations:
18 mg/L nominal, 12 mg/L measured
Details on test conditions:
Aliquots of the vinyl neononanoate stock test solution were transferred to triplicate flasks and inoculated with algae. Algae were incubated under standard test conditions and cell counts were measured every 24 hours using a hemacytometer and microscope. In addition, an aliquot of the 18 mg/I test solution was placed in a sealed glass tube with nc headspace present. This sample was used to determine the test substance concentration in a closed system after 96 hours.
Reference substance (positive control):
no

Results and discussion

Effect concentrationsopen allclose all
Duration:
96 h
Dose descriptor:
NOEC
Effect conc.:
12 mg/L
Nominal / measured:
meas. (arithm. mean)
Basis for effect:
cell number
Duration:
96 h
Dose descriptor:
EC50
Effect conc.:
> 12 mg/L
Nominal / measured:
meas. (arithm. mean)
Basis for effect:
cell number
Details on results:
The algal cell counts in the 12 mg/L vinyl neononanoate treatment and control cultures were subjected to a student t-test which indicated no significant difference (p <0.05) between them after 72 and 96 hours. Logarithmic phase growth was confirmed at 96-hr with a mean cell count of 3.3 x 106 cells/mi in the control replicates. The 24-hi; 48-hi; 72-hr, and 96-hr EC5O values were estimated to be >12 mg/L. The 96-hr NOEC based on absence of growth inhibition was 12 mg/L. .
Reported statistics and error estimates:
Student's t-test

Applicant's summary and conclusion

Validity criteria fulfilled:
yes
Conclusions:
The static 96 hr acute LC50 value for green algae was > 12mg/L as measured.
Executive summary:

The 96 -hour EC50 value for Selnastrum capricornutum exposed to vinyl neononanoate under static conditions was > 12 mg/L and the no observed effect level was 12 mg/L, based on the absence of a growth inhibition.