Ethyl cyanoacetate

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: GLP LAB testing

Data source

Reference

Reference Type:

study report

Title:

Unnamed

Year:

1992

Materials and methods

Test guideline

Qualifier:

according to guideline

Guideline:

other: Directive 88/302/EEC Algae growth inhibition

GLP compliance:

yes (incl. QA statement)

Test material

Test material information

Constituent 1

Reference substance name:

Ethyl cyanoacetate

EC Number:

203-309-0

EC Name:

Ethyl cyanoacetate

Cas Number:

105-56-6

Molecular formula:

C5H7NO2

IUPAC Name:

ethyl 2-cyanoacetate

Details on test material:

Purity/components 99.7%
Colorless liquid
Tank 434

Sampling and analysis

Analytical monitoring:

yes

Test organisms

Test organisms (species):

Desmodesmus subspicatus (previous name: Scenedesmus subspicatus)

Study design

Test type:

not specified

Water media type:

not specified

Total exposure duration:

72 h

Test conditions

Test temperature:

24±2℃

pH:

At the beginning 7.1-7.8
At the end 3.5-8.7

Nominal and measured concentrations:

Nominal concentrations: 10, 17, 30, 50, 80 and 140 mg/l

Details on test conditions:

Preparation of the test stock solution: 1g/l
light intensity: 8000 lux, white

Results and discussion

Effect concentrations

Effect concentrations 1

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

72.4 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

cell number

Effect concentrations 2

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

17.9 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

cell number

Effect concentrations 3

Duration:

72 h

Dose descriptor:

EC50

Effect conc.:

141.9 mg/L

Nominal / measured:

nominal

Conc. based on:

test mat.

Basis for effect:

growth rate

Effect concentrations 4

Duration:

72 h

Dose descriptor:

EC10

Effect conc.:

29.9 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:

72h Er 50=72.4mg/l according to cell number.

Executive summary:

Summary

The influence of ethyl cyanoacetate subspicatus on the growth of the unicellular green algae Scenedesmus was studied in Algae growth inhibition test according to EC Directive 88/302.

 

The following effect levels based on the product were obtained:

Based on the cell growth effect, an average concentration of computed

 72h EbC50: 72.4 mg / 1

a 10% inhibition of cell growth is achieved at

 72h EbC10: 17.9 mg / 1,

 

Based on the growth rate in a mean effect concentrations calculated

(0-72h) ErC50: 141.9 mg / 1 *,

a 10% inhibition of growth rate is achieved at

  (0-72h) ErC10: 29.9 mg / 1

* Highest tested concentration amounts to 140 mg / 1

NOEC of 17 mg / 1

(≤10%, based on the number of cells after 72 h) All concentrations refer to the product.

 

Note: During the 72 hour test period, the test substance hydrolyses and it comes at the higher test concentrations (from 30 mg / 1) to a decrease in pH, which are in the range of EC values​ ​significantly in acid. A influence on the test results cannot be excluded.